Delivery of nucleic acids to cells have been performed using viral vectors, lipid delivery systems, and electroporation. However, polyanionic oligomers such as oligonucleotides do not readily diffuse across cell membranes. Attempts to overcome this limitation are complex and generally toxic to cells. The idea of RNA interference (RNAi) as a mechanism to the development of targeted therapeutics was proposed, however, due to their size and negative charged nature, these siRNAs do not have the ability to enter cells. (more...)

Pulmonary Hypertension (PH) is characterized by high blood pressure in the arteries of the lungs that can lead to heart failure. PH is a chronic, debilitating disease characterized by pulmonary vascular remodeling, vasoconstriction, fibrosis, inflammation, right ventricular (RV) hypertrophy and RV failure. Pulmonary arterial hypertension (PAH) has an estimated prevalence of 15-50 cases per million. The prevalence of PAH in certain at-risk groups including patients with HIV, systemic sclerosis, and sickle cell disease is substantially higher. Idiopathic PAH (IPAH) has an annual incidence of 1-2 cases per million people in the US and Europe and is 2-4 times as common in women as in men. According to a report by Cleveland clinic, since 1980, the numbers of deaths and hospitalizations and the rates of death and hospitalization have increased for pulmonary hypertension, particularly among women and older adults. (Raed A. Dweik et al. January 2011). Current treatments for pulmonary hypertension can only improve patients’ symptoms temporarily; however, gradual deterioration in their condition often necessitates a lung transplant. The identification of a miRNA that is capable of restoring the pulmonary arteries and RV function would provide a promising therapeutic strategy for the treatment of pulmonary hypertension.  (more...)

Current systems used to perform sample preparations that integrate with digital microfluidics use liquid valves, rotary valves, or small volume injection loops that are expensive and often require a large apparatus to operate. Other digital microfluidic systems require operators to directly pipette sample reagents into the platform which can incorporate human error and the potential exposure to hazardous chemicals. In order for automated and consistent benchtop chemical synthesis using digital microfluidics to exist, a compact and inexpensive system must be able to interface with the external environment to allow efficient chemical delivery and retrieval. (more...)

Micro-scale particles in flow can be found in many fields of science and technology. One example is cells in blood stream.  Control of particle motion/position in flow has numerous applications such as flow cytometry and particle encapsulation.  Control of particle positions in particle laden flows is typically achieved by external force fields such as acoustic, electric, or magnetic fields.  However, such methods consume power, require a bulky setup and efficiencies degrade with increasing flow rate, thus lowering the throughput.  Recently, fluid inertia has been used to manipulate particle position in flow with high throughput in the transverse direction (particle-wall spacing), but not the lateral direction (particle-particle spacing).  Although studies to date have provided simple descriptions of lateral spacing phenomena as a function of particle Reynolds number, the mechanisms of self-assembly in these systems are not well understood and have not been engineered effectively. (more...)

Flow cytometry is regularly used for patient blood analysis. Because, flow cytometry analyzes cells in a serial process, it is time consuming and lacks sufficient throughput (current methods top out at 10,000 cells/sec) to detect rare cells in blood or other dilute solutions which can have concentrations in the range of one in one quadrillion (1:1015). In addition, flow cytometry has high operating costs, lacks portability, and requires dedicated personnel and is therefore impractical for point-of-care use. Because the global flow cytometry market is projected to exceed $1.5 billion with an annual growth above 10%, great attention is being paid to microfluidic devices for healthcare applications. Microfluidics devices offer a significant reduction in cost, increase in portability, and higher throughput efficiency than flow-cytometry with comparable or better sensitivity.          (more...)

Disturbances in endothelial gene expression contribute to vascular morphogenesis and tumor growth. Over the past century, the mouse has emerged as the premier mammalian model system for genetic research. Its genetic and physiological similarities to humans, as well as the ease with which its genome can be manipulated, make it especially attractive as models for human disease. Thus, mouse models that enable genetic tracing of endothelial cells would be of great use to vascular biologists.      (more...)

Nuclear Magnetic Resonance (NMR) spectroscopy is a widely-utilized method for analyzing small molecule compositions. It is among the most sensitive techniques available and has great potential for studying metabolic profiles in living organisms. Since variations in the metabolite concentrations are indicative of many disease states, NMR can be a powerful diagnostic tool. In practice, however, this requires sensitivity still beyond the capabilities of current instruments. As a result, using NMR for diagnostic purposes has been limited to academic research. A key component responsible for the sensitivity is the NMR probe, which holds the sample as it is inserted into the magnetic field. Advancing the probe design is critical to enabling practical medical applications of NMR. (more...)

Cell-based systems for in vitro biomarker profiling of drug efficacy or discovery. (more...)

Together, the specificity of engineered antibodies and the diagnostic power of in vivo imaging provide a tremendous opportunity for exploring disease pathogenesis. CD8 is expressed on a subtype of T cells, known as cytotoxic T cells as well as a subset of dendritic cells. CD8+ T cells are the subject of intense research efforts, including those for developing cellular immunotherapies and for understanding tumor oncology.  The present invention describes a functional CD8-imaging agent based on engineered antibodies.  The agents have clear use in a variety of preclinical disease and immuno-therapeutic models. The ability to monitor the migration, expansion, and longevity of therapeutically transferred cells using molecular imaging technologies is of critical importance for developing immunomodulating therapies.  (more...)

Prostate cancer is one of the most common cancers to affect men and is the second leading cause of death amongst cancer victims. For decades, primary cultures of malignant prostatic cells have provided a convenient model system to study prostate cancer and tumorigenesis. However, these cell lines do not adequately recapitulate the microenvironment that supports tumor development in vivo. Many of the available prostate cancer cell lines (PC3, DU145, and LNCaP) are derived from metastases and are not inclusive of all prostate cancer phenotypes. Thus, there is a need for cell culture model systems that more effectively recapitulate the genetic and environmental composition of tumors. Seminal work carried out by Dr. Garraway's research group at UCLA has provided crucial insight into the development of a novel cell line derived from human fetal prostate tissue for the study of prostate tumors and tumorigenesis.       (more...)

Lentiviruses are considered optimal viral vectors for use in gene therapy, because they transduce non-dividing cells and offer stable integration into the target cell's genome. The cell type(s) that a lentiviral vector is capable of infecting is determined by the expression of surface glycoproteins. Packaging a lentiviral vector with surface glycoproteins from a different virus is known as pseudotyping. Current gene therapy relies on pseudotyping with a glycoprotein from vesicular stomatitis virus, known as VSV-G, which has a ubiquitous host cell receptor, allowing infection of most cell types with this pseudotyped virus. While VSV-G pseudotyped viruses are the current gold standard of gene therapy, there are several drawbacks to this method. First, VSV-G is toxic at high levels, limiting the concentration of virus that can be administered to target cells. Secondly, VSV-G pseudotyped viruses cannot be targeted to specific cell types in vivo, since VSV-G recognizes a host receptor expressed on all cell types. Finally, when VSV-G-pseudotyped viruses are administered to mice in vivo, the virus accumulates in the liver, making it difficult to target cells in other organs or tissues. Thus, lower toxicity and higher cell type-specificity viral vectors are needed to improve the potential of gene transfer treatments.        (more...)

Researchers at the University of California, Irvine have developed a nanofluidic device that may be used to trap and analyze single mitochondria. (more...)

Stem cell therapy holds the promise of treating a variety of human conditions such as diabetes, cancer, and neurological diseases. It is thought that stem cells could be especially useful for neurological diseases and disorders as the brain has a limited capacity for self-repair and regeneration. There are no effective long-term treatments or cures for certain brain disorders or neurodegenerative diseases such as Alzheimer’s and Parkinson’s disease. Collectively, these conditions represent a significant unmet medical need. Regenerative approaches for the brain have the potential to address the cause of the disease, rather than simply addressing symptoms, by repairing or reversing the disease state. In addition, cancer relapse has recently been attributed to the existence of cancer stem cells, which are resistant to traditional therapies, exist in numbers too small for detection, and have the potential to develop into new tumors. Treatments that target cancer stem cells would represent a great advance in the field of cancer medicine, and significantly improve prognosis and quality of life for patients by preventing relapse and metastasis. (more...)

Treating blood loss with cell free oxygen carrier (artificial blood) is essential to maintain oxygen supply to the patient as well as prevent the collapse of capillaries. Effective substitution by artificial blood hinges on oxygen delivery, blood-gas and pH balance, and carbon dioxide removal. Therefore it is important to monitor the efficacy of the artificial blood or compare the efficacy of different types of them. (more...)

A number of diabetogenic stimuli interact to influence insulin promoter activity. High-Throughput Screening (HTS) for insulin promoter modulators has the potential to reveal novel inputs into the control of that central element of the pancreatic β-cell. HTS for insulin promoter modulators can both serve to identify compounds that can serve as a treatment to diabetes as well as identify unintended side effects of insulin promotion in other drug candidates. (more...)

Rapid, efficient, and low cost detection and identification of microorganisms including pathogenic bacteria, viruses, and fungi is a challenge facing plant and animal health. Current technologies such as Q-PCR rely on multiple assays and amplification methods to identify bacteria and viruses. Traditional optical detection methods also require fluorescent markers. These multiple independent steps and tests increase the processing time and cost for detection and identification. Researchers at the University of California, Davis, have developed a technique that uses nanotechnology to electrically detect and identify bacterial and viral RNA sequences without the necessity of using enzymatic amplification methods or fluorescent markers. In cases where microbe densities are particularly low, the technique provides additional sensitivity that allows for the target molecules to be detected in small quantities. Furthermore, the technique may be scaled into large multiplexed arrays for high-throughput and rapid screening. The implementation is further able to differentiate closely related variants of a given bacterial or viral species or strain. This technique addresses the need for a quick, efficient, and inexpensive bacterial and viral detection and identification system. (more...)

As much as 15% of the adult population exhibits symptoms of irritable bowel syndrome (IBS), a disorder characterized by abdominal pain, diarrhea and/or constipation, bloating, and discomfort. Although IBS does not cause permanent harm, it can render sufferers unable to work, attend social events, or even travel short distances. IBS is also associated with significant health care costs and economic burden. Lacking well-defined and specific diagnostic criteria, physicians currently diagnose IBS on the basis of a complete medical history, physical examination, and other assays. These may include invasive procedures such as sigmoidoscopy or colonoscopy. As such, there is a need for a simple and reliable method to diagnose this condition, as well as a therapeutic target for drug development. (more...)

Because of significant improvements made in the treatment of primary cancers, distant organ metastases caused by hematogenous spread of tumor cells are now responsible for the majority of cancer related deaths in solid organ malignancies. Dissemination of tumor cells into the circulation is now considered an early disease event and a variety of studies have demonstrated that these cells can be detected in the blood of cancer patients even when the tumor appears localized. Furthermore, the presence or absence of these so called Circulating Tumor Cells (CTCs) has been demonstrated to have prognostic significance and is taken into consideration when staging a tumor. Other studies strongly suggest that the presence of CTCs may be able to predict disease recurrence in patients in remission. Because cancers generally become more difficult to control once they have spread beyond the primary tumor site, timely detection of CTCs holds significant value in charting disease progression and tailoring more appropriate interventions. Thus, numerous companies are actively developing technologies for sensitive and specific detection of CTCs in patients. To date, CellSearch™ System developed by Veridex (now part of Johnson & Johnson) is the only device which has received approval by the US Food and Drug Administration for this purpose. (more...)

High-throughput, automated, large-scale mircoarry format assay in a short time frame and at low cost. (more...)

A UCSD Researcher has developed a method to fabricate microfluidic features into a single layer microfluidic device. All current microfluidic methods for fabrication require two layers. The advantages of a single layer is that tooling costs are lowered, there will be improved manufacturing yields, and improved compatibility with traditional injection-molding processes. Here, the researcher has made the chips with single layer valves and successfully tested these for functionality.In addition, source files for the design, fabrication and operation of the devices have been developed. (more...)

Liver cancer is among the most lethal cancers, the third and sixth most frequent cause of cancer death in men and women, respectively.  Amongst the several histologically different primary hepatic malignancies, hepatocellular carinoma (HCC) accounts for 70 to 85% of the cases.  Animal models that mimic features of liver tumor development in human are invaluable research tools for understanding the mechanism of liver carcinogenesis and developing new drugs for treatment of patients with HCC. (more...)

Abdominal aortic aneurysm (AAA) is a severe human vascular disease resulting in progressive aortic dilation and eventual lethal rupture. Approximately one in every 250 people over the age of 50 will die of a ruptured AAA. While the success rate of surgical repair is high for aneurysms bigger than 5cm, reliable prediction of the asymptomatic disease remains elusive. Moreover, smaller instances of the disease cannot be easily diagnosed with radiography, or ultrasound, potentially resulting in silent growth and sudden rupture. Even CT and MRI will not be able to detect aneurysms at the early initiation stage that only involve molecular remodeling of the aortas. Thus, there is an urgent need for a more robust and sensitive method to predict AAA development at very early stages to enable better monitoring and treatment of the disease. (more...)

Researchers at the University of California, Irvine have developed a novel method and device for cell separation that does not require cell labeling. (more...)

Fluorescence tomography (FT) is a sensitive but intrinsically low spatial resolution imaging modality due to strong photon scattering in biological tissue. Recently, a temperature-responsive fluorescence contrast agent has been reported using ICG loaded pluronic nanocapsules. The temperature dependence of these contrast agents provides a major opportunity to overcome the spatial resolution of regular FT by using temperature modulation/tagging.Researchers at the University of California, Irvine have developed a new molecular optical imaging modality termed “temperature-modulated fluorescence tomography (TM-FT)” that can provide high resolution images without sacrificing the exceptional sensitivity of fluorescence-based detection. TM-FT is based on the temperature modulation of fluorescence quantum efficiency in a highly scattering medium. The medium is irradiated by both excitation light and a high intensity focused ultrasound (HIFU) wave. The crucial benefit of HIFU is that the temperature of the medium is modulated with a very high spatial resolution (~1.5 mm) due to the absorption of acoustic power in the ultrasound focal zone. When the temperature sensitive fluorescence agent presents within HIFU focal zone, the local temperature increases and in turn, changes the fluorescence quantum efficiency inside the focal zone. As a result, the emitted fluorescence light intensity and lifetime have detectable change only when the agent is present within the focal zone. In other words, it allows fluorescence reconstruction with high spatial resolution by scanning focused ultrasound column over the medium while detecting the change in fluorescence signal. Using a proper reconstruction algorithm, this technique can also provide quantitatively accurate fluorescence images. Finally, the temperature sensitive agents can be modified to target molecular pathways and processes associated with many diseases and hence, TM-FT technique can provide a suitable platform for true molecular in vivo imaging. (more...)

The method is a novel and convenient method to chemically modify the exterior surface of enveloped viruses so that such viruses can be easily purified. This chemical modification on the envelope of the virus is reversible. (more...)

Stem cells are capable of both self-renewing and differentiating into more specialized cells. These two defining characteristics make stem cells a powerful tool for biological research, as they provide the potential to regenerate tissue in a living organism and grow organs in culture.Our ability to probe human stem cell fate has been hindered by the inability to create cellular microenvironments that provide a platform to spatially program stem cell fate.  The invention described here provides the cellular microenvironment required to  investigate the signaling molecules involved in the induction of stem cell fate.  (more...)

HBV infection can lead to chronic infections that result in 0.6 million deaths per year worldwide by causing liver failure and cancer. Clearance of HBV infection is age dependent, with the majority of adult-acquired infections leading to spontaneous clearance, whereas infection in young children often leads to chronic infections. To study these early events of infection and immune activation that lead to HBV clearance or persistence, in vivo models are needed to screen and validate lead drug candidates. HBV cannot infect mice, however, researchers at UCSF have generated transgenic mouse models that mimic critical features of primary HBV infection observed in humans. (more...)

The Dixdc1 protein may play an important role in the pathogenesis of schizophrenia, major depressive disorder, bipolar disorder, autism and other major psychiatric disorders.  In addition, Dixdc1 may also contribute to cancer metastasis, invasiveness and planar cell polarity.  Molecular signaling pathways potentially involving Dixdc1 include the Wnt/b-catenin, Nde1/CDK5 and the TGF-b pathways.  Importantly, Dixdc1 protein is an establised partner of the Disc1 protein, the product of one of the best-established neuropsychiatric susceptibility genes (DISC1).  Previous studies have utilized RNA interference to knock down Dixdc1 protein.  However, a genetic knockout in mice, an important rsearch tool that would be very useful for studying Dixdc1 function in disease, has not been described in the scientific literature to date. (more...)

Our research indicates that the Sestd1 protein may play an important role in oncogenesis, metastasis, wound healing and stem cell biology.  Molecular signaling pathways involving Sestd1 potentially include the Wnt/b-catenin pathway, the Wnt/PCP non-b-catenin-dependent pathway, regulation of small GTPase of the Rho family, and other pathways involving the Dishevelled signal transduction molecule, such as p120-catenin signaling.  Sestd1 may also be involved in the regulation of the TGF-b pathway.  In vitro and in vivo knockdown models would be very useful for studying Sestd1 function in disease but have not been reported to date. (more...)

Superhydrophobic surfaces have attracted tremendous attention due to their self-cleaning, anti-contamination, and anti-sticking properties. Conventional methods used to create superhydrophobic surfaces include creating a rough structure on a hydrophobic surface or modifying a rough surface by materials with low surface free energy. In many instances, these conventional methods utilize expensive materials or time-consuming procedures to obtain the desired surface properties. Newer, less expensive methods to generate superhydrophobic surfaces will allow this unique property to be more accessible for a multitude of applications. Researchers at the University of California, Irvine have developed a new process to create superhydrophobic surfaces. The method uses only an inexpensive bench-top plasma etcher common to most microfluidic laboratories and achieved superhydrophobic surfaces in PDMS without any chemical modifications. By using this technique, the inventors were able to fabricate a micro droplet array for easy manipulation of liquids. (more...)

The 26S proteasome is the macromolecular machine of the ubiquitin proteasome-dependent degradation pathway that is responsible for most of the nonlysosomal protein degradation in both the nucleus and cytosol. It is involved in many important biological processes such as cell cycle progression, apoptosis, and DNA repair. Human proteasome complexes are conventionally purified by ultracentrifugation and multiple chromatographic techniques, which are time consuming and require a lot of materials. A strategy that allows for fast and effective purification of human proteasomes will be an important research tool. Researchers at the University of California, Irvine have developed a new affinity purification strategy for rapid and effective isolation of the human 26S proteasome. The 293 cell line is robust and can stably express Rpn11-HTBH. It is a cell line that allows the affinity purification of the human 26S proteasome under both native and denaturing conditions. It allows the purification of the human 26S proteasome complex after in vivo cross-linking. (more...)

MeCP2 is a methyl-CpG binding protein that binds methylated DNA to repress gene expression. Mutations in MeCP2 lead to neurodevelopmental disorders, including Rett syndrome, one of the most common causes of mental retardation in females. Phosphorylation of MeCP2 on a highly conserved serine residue (S80) is required for its roles in regulating gene expression and neurological function. Moreover, mutations at this S80 residue have been identified in Rett patients and result in neurological deficits in mouse models. UCLA researchers have developed a polyclonal antibody that specific recognizes MeCP2 phosphorylated at S80 in both human and mouse. It can be used to study the function of this activated form of MeCP2 in neurological disease or to screen for potential therapeutics for Rett syndrome. (more...)

Bladder cancer is the fifth most common cancer in the United States, with approximately 67,000 new cases diagnosed in the U.S. every year. It also has a high recurrence rate (50-80%), so diligent surveillance is necessary to monitor patient health. Cystoscopy, a procedure in which a cystoscope (thin, telescope-like tube with a light and tiny camera attached) is used view the bladder by insertion in the urethra, is top method to monitor for bladder cancer recurrence. However, the procedure is costly and requires the patient to be under local anesthesia in a doctor’s office. Physicians at the University of California, Irvine have developed a single use disposable camera that may be inserted into the bladder to image it. This camera would stay in the patient’s body and allow for continued monitoring of the bladder between doctor’s visits. In addition to monitoring for bladder cancer recurrence, this camera would be useful for any application in which cystoscopy is used. For example, this novel camera could be used for evaluation and diagnosis of blood in the urine (hematuria), chronic pelvic pain, frequent urinary tract infections (UTIs), interstitial cystitis, urinary incontinence and other problems of the urinary tract. (more...)

Centrifugal microfluidic devices find extensive use for in vitro diagnostics. One of the most important considerations in developing a microfluidic device is determining how the liquids will be transferred in a controlled manner. The discovery of new methods for controlled release of liquids is an area of significant importance in the future development of microfluidic technologies. Researchers at the University of California, Irvine have developed a method for controlled release of liquids on a centrifugal platform. This invention has the ability to store liquid on a centrifugal microfluidic platform and, when needed, is able to transfer this liquid to any location on the platform independent of its proximity to the center of rotation. The invention is a non-contact method, uses stable materials, and would be easy to assemble in a mass manufacturing setting. (more...)

The Human Immunodeficiency Virus (HIV) has evolved a number of mechanisms of evading the human immune system.  One way is through a high level of mutation, which makes it difficult to develop a vaccine that stimulates protective immunity against all of the different HIV variants.  Therefore, scientists are searching for a general surrogate marker that could be used to target any HIV-infected cell regardless of its mutational status, enabling eradication of the virus. In this regard, scientists at UCSF have recently begun to take a closer look at Human Endogenous Retroviruses (HERVs) that are present in all human cells.  HERVs are a family of retroviruses found in the human genome and are thought to have originated from an ancient retrovirus that become permanently integrated with the DNA of its host's germ cells.  HERV viruses are inactive in normal cells but one type of HERV, HERV-K, is activated in HIV-infected cells.  The HERV-K proteins are presented on the surface of HIV-infected cells.  Because HERV-K is expressed in all HIV-infected cells, it is thought HERV-K antigens presented on the surface could be a good candidate to generally target any HIV+ cell. (more...)

Interstitial lung disease (ILD) is a common manifestation of systemic autoimmune diseases such as rheumatoid arthritis (RA), lupus and scleroderma, which can lead to inflammation and scarring of the lung and, consequently, to hypoxemia, pulmonary hypertension and death.  It is estimated that ILD occurs in approximately 15 percent of patients with RA.  Very little is known about how ILD disorders arise and what role loss of immune tolerance plays in ILD development.  Presently, there are no validated lung-specific autoantigens for diagnosis of autoimmune-mediated lung disease.  Current options for ILD treatment are limited to powerful immunosuppressive medications with significant side effects.  Identification of novel pulmonary biomarkers is sorely needed to develop better diagnostic methods and therapies for ILD. (more...)

Leveraging from microfabrication techniques originally developed for the microelectronics industry, researchers have been able to create simple designs such as well-defined and repetitive patterns of grooves, ridges, pits, and waves.Techniques such as photolithography, electron-beam lithography, colloidal lithography, electrospinning, and nanoimprinting are popular methods for fabricating micro and nano topographical features.However, the need for large capital investments and engineering expertise has prevented the widespread use of these fabrication methods in common biological laboratories.Researchers at the University of California, Irvine have developed an ultra-rapid, robust, and inexpensive fabrication method to create multiscaled grooves, ranging from micron to nanometer in size, as biomimetic cell culture substrates.This method only takes a few minutes to perform and does not require any metal deposition.In addition, the size of the nanowrinkles is easily tuned for a multitude of biological applications. (more...)

Although every cell contains the entire genome of the organism, only some of the genes are transcribed and translated in a particular cell type. Cellular functions can, therefore, only be understood once each cellular proteome is known. One of the most important tools in identifying all of the proteins and their post-translational modifications in a particular cell involves digesting the entire mixture of proteins all at the same time, and then piecing the sequence information back together at the end. Nearly all proteomics studies are carried out with a single protease digestion step using trypsin. Sequence coverage of abundant proteins using currently available proteases may approach 50 percent but sequence coverage of most proteins is less than 10 percent. In order to increase the sequence coverage, proteases of alternative specificity are needed. (more...)

The fidelity of detection in a biosensor is limited by the ability of the device to identify small quantities of analyte in the presence of much larger quantities of interfering molecules. Separation, preconcentration, and detection of the analyte are key aspects of the analysis, and the drive to decrease sample volumes and increase throughput has led to chip-based systems that combine these components within a volume of a few cubic micrometers. Electric fields, applied via external electrodes or photogenerated in a semiconducting matrix, are often employed to enhance biomolecular separation in such systems. For example, electroadsorption provides a means to concentrate a charged analyte on an electrode surface, and electrophoresis induces migration and separation of charged species. (more...)

Surfaces are frequently micropatterned with proteins in order to capture and culture cells in distinct gerometric configurations. Researchers at UC Davice have developed a novel method for micropatterning surfaces with photoliabile protein to capture and release of cells, triggered by UV light. (more...)

Optical microscopy methods have tremendous application in the study of cells and other biological structures.Current imaging methods, such as STED and PALM, have allowed scientists to capture super-resolution images that have been difficult in the past.However, these current imaging methods are inadequate to detect the dynamic movements of live cell structures which are continually changing shape and position in the millisecond to second time scale.In addition, current scanning techniques, which utilize laser scanning in a predetermined pattern, are inefficient when the features to be imaged are at the nanometer scale.A method that is effective at capturing super-resolution images of dynamic, nanoscale biological samples will be an important scientific tool. Researchers at the University of California, Irvine have developed an optical imaging method that can produce 3D images of small, moving cellular structures with fluorescent surfaces.The method is based on a feedback principle according to the shape of the objects present in the sample, instead of having a predetermined path.The feedback approach produces high quality 3D images in seconds and does not require sample fixation.This method works with live cells and is compatible with correlation techniques like FCS and RICS. (more...)

Stem cells hold the promise of producing functional tissues that can replace those lost due to disease or injury. Stem cells exhibit "pluripotency," meaning that they have the potential to become any cell type in the body. New organ tissues, such as those found in the heart, liver, or nervous system, can be created from stem cells through the process of "differentiation." However, one major challenge in developing tissue replacement therapy is the heterogeneity and low yield associated with stem cell differentiation. It is well established that mechanical factors of the cellular microenvironment, including cell shape and density, influence stem cell differentiation and cell behaviors in general. Stem cells form isolated colonies in culture, and the geometry of these colonies can have a profound impact on their capacity for differentiation. There is currently a commercialized technology for controlling the size and shape of embryoid body formation and it has been shown that the size of embyroid bodies is important for differentiation. But many differentiation techniques do not involve the formation of embryoid bodies, and instead induce differentiation from 2D monolayer cultures of stem cells. Current 2D stem cell culturing protocols lack control over colony geometry because they allow for random attachment to tissue culturing surfaces. This leads to unpredictable stem cell growth which ultimately hurts our ability to successfully control the cell fate and differentiate into specific cell types. By patterning an extracellular matrix (ECM), such as Matrigel, colony formation, growth, and geometries can be highly regulated. By using silicone stencils a standard tissue culture plate can be converted into a cell patterning substrate while still using the normal ECM plating procedures. (more...)

Throughout development, cells and tissues differentiate and change as the organism ages. Both differentiation of tissues and ageing effects are at least partially caused by chemical modifications of the genome, such as DNA methylation. It was previously shown that significant DNA methylation differences are associated with specific age-related disorders, such as late-onset Alzheimer's disease. Measuring the methylation level at relevant sites in the genome could be used in routine medical screening to predict the risk of age-related diseases and increase our understanding of ageing in patient health. (more...)

UC Davis researchers from the NSF Center for Biophotonics and UC Davis Health System have developed a method of identifying and sorting cardiomyocytes derived from human pluripotent stem cells.  This method, based on second harmonic generation (SHG) - a nonlinear optical technique, does not require genetic modification of the cell or any exogenous labels to be used, which makes this an attractive technique for obtaining pure populations of cardiomyocytes under xeno- and vector- free conditions most appropriate for clinical and therapeutic use, as well for tissue engineering and drug discovery applications.There are currently no established methods for sorting pur populations of stem cell derived cardiomyocytes.  Methods that use fluorescent reporters require the introduction of a reporter vector and result in genetically modified cells, reducing their utility for clinical applications.  Other fluorescent-based staining methods have shown to be only applicable for selecting very mature cardiomyocytes.  Surface marker based methods require exposing human cells to products of animal origin, which may increase the risk of non-human pathogen transmission and render the cells unsuitable for clinical use.Second harmonic generation (SHG) is a laser-based technique that identifies stem cell derived cardiomyocytes based on the direct detection of myosin bundles, which generates a unique second harmonic signal when excited by intense laser pulses.  This signal is specific to the cardiomyocyte phenotype and is absent from undifferentiated stem cells and other non-cardiomyocyte cells that are found in the population following the directed differentiation of stem cells to the cardiac lineage.  SHG is able to discriminate cardionmyocytes at different stages of maturation/development, and can detect very immature cells.  When integrated into a flow cytometric configuration, non-invasive sorting for pure populations of stem cell derived cardiomyocytes is feasible. (more...)

The invention provides methods and devices in which microscopic particles or cells within a fluid flowing in microfluidic channels are selectively manipulated, normally by being pushed with optical pressure forces at branching junctions in the channels so as to enter into selected downstream branches, thereby realizing particle switching and sorting. Transport of the particles thus transpires by microfluidics while manipulation in the manner of optical tweezers arises either from pushing due to optical scattering force, or from pulling due to an attractive optical gradient force. Whether pushed or pulled, the particles within the flowing fluid may be optically sensed, and highly-parallel, low-cost, cell- and particle-analysis devices thus may be efficiently realized, including as integrated on bio-chips. (more...)

Use of synthetic nucleic acids to manipulate gene function has become a powerful tool for both basic research and therapeutics.  Silencing disease targets by RNA interference is a promising approach to drug development, and various experimental RNA therapies are currently in clinical development by both small and large biotechnology companies.  miRNAs are also being developed for disease treatment and diagnosis.  However, lack of specifically targeted, efficient and safe vehicles for systemic delivery of small RNA payloads in vivo is a serious challenge.  Synthetic nucleic acids face a number of physiological barriers in the bloodstream, and their intracellular uptake is hampered by the fact that they are highly charged and have much larger molecular wieght than small-molecule drugs.  Current strategies to circumvent these problems includes local administration, chemical modifications of nucleic acids, viral delivery vectors, lipid-based delivery systems, polymer-based delivery systems and nanoparticle encapsulation.  These methods have serious flaws including toxicity, inummue effects, non-selectively and high cost of manufacturing.  Therefore, novel ways to deliver synthetic nucleic acids for use in humans and experimental animal models are sorely needed. (more...)

Human skin is exposed to a multitude of chemicals on a daily basis, many of which can be hazardous or induce an irritant reaction.  While there is strict government regulation in regards to screening of these chemicals, this testing has typically relied on the use of animal models.  However, in recent years the use of in vitro screening methods has become more prominent, with reconstructed human epidermis models being a preferred technique.  Unfortunately, this approach is both time-comsuming and expensive, as well as being difficult to develop as a high throughput screen. (more...)

The ability to map important brain regions (e.g. sensory and motor cortex) is critical for surgical procedures that require precise information of neural activity so that neurosurgeons can safely operate. The current state of the art relies on electrical cortical stimulation that is not only inefficient but also relies on electric shock thereby generating non-physiologic activity from the areas sampled, and such stimulation can also cause dangerous seizures. Furthermore, electrical stimulation mapping frequently misrepresents and underestimates the extent of the functional cortex, leading to neurologic impairments in patients despite comprehensive mapping. Additionally, inaccurate mapping by electrical stimulation may also lead to incomplete resection of a tumor or epilepsy focus to preserve the tissue whose function is not clearly identified or incomplete, resulting in tumor regrowth or continued intractable seizures, respectively.   What neurologists and neurosurgeons need is a safe and efficient functional brain mapping tool that will allow them to accurately perform cortical tissue resections without compromising critical brain regions. (more...)

Coherent anti-Stokes Raman scattering (CARS) microscopy, a form of nonlinear optical microscopy, has gained enormous attention in the biomedical community for its potential to provide high resolution images at fast imaging acquisition rates. Typical applications of CARS include skin and superficial tissue imaging, often in an in vitro setting. Up to this point, a suitable device that enables the CARS imaging of tissues in vivo has not been available. However, researchers at the University of California, Irvine have developed a novel, fiber-based imaging probe that is optimized for CARS to enable the label-free,in vivo probing of tissues. (more...)

Determination of stem cell fates, including ascertaining the differentiation status and forecasting the outcome for a given stem cell or stem cell colony, is critical in regenerative medicine and tissue engineering. However, commonly employed procedures for making such determinations, such as immunofluorescence and flow cytometry, can involve time-consuming and costly sample preparation and often (especially for human stem cells) require the sacrifice of the cells during the assay process. It would be highly preferable to employ procedures that are faster, less intrusive, and less expensive. (more...)

Diacylglycerol acyltransferase-1 (DGAT-1) is an enzyme involved in triglyceride synthesis.  Inhibitors of DGAT-1 are currently in clinical trials as treatments for diabetes and obesity. (more...)

There are approximately 20-40 million people in the United States with sleep apnea. Obstructive sleep apnea has been recognized as a very common disorder and an important cause of morbidity and mortality. Obstructive sleep apnea is characterized by repetitive interruptions of breathing during sleep due to the collapse of the upper airway. Sleep apnea can lead to severe health complications including hypertension, heart failure, memory impairment, motor vehicle and work accidents, decreased work productivity, and increased risk of death. The development of a novel, simple, rapid, minimally invasive method for the diagnosis and optimization of treatment of patients with obstructive sleep apnea would be a tremendous advance for these millions of patients. Optical coherence tomography (OCT) is an imaging modality that can perform cross section views of tissue. OCT is analogous to ultrasound except that imaging is performed with light instead of acoustic waves. OCT is non invasive and non ionizing allowing study over lengthy periods during both sleep and wakefulness. Conventional OCT which is based on time domain technique has very limited imaging speed which precludes its use in real-time, dynamic monitoring and large volume detection. Researchers at the University of California have developed a technique including the step of combining a narrow line-width sweptsource based Fourier domain OCT (FDOCT) system with an endoscopic probe to enable an ideal upper airway imaging technology which is low-cost, compact, noninvasive, non-ionizing, dynamic (to visualize apneic events), suitable for supine position study, and capable of high resolution three dimensional images. This technology provides a mechanism for dynamic evaluation of obstructive sleep apnea. (more...)

Researchers at the University of California, Irvine have developed a novel method for capturing cellular resolution images of biological tissue at depths of up to several millimeters. Conventional fluorescence detection methods utilize microscope objectives for emission light collection, a less effective approach that is only capable of imaging up to one millimeter deep.To improve upon this standard, the UC researchers minimized light losses by optimizing the system’s excitation and detection optics. (more...)

Asthma, a chronic inflammatory disease of the lung, affects an increasingly larger population every year and presents a major public health problem in terms of morbidity and cost. The cause and mechanisms of asthma and allergic diseases are not yet understood. As the spontaneous development of asthma in a non-human animal is next to impossible, the ability to engineer mouse models of the disease remains critical to the understanding and treatment of the disease. (more...)

Researchers at the University of California, Irvine have developed a novel method to continuously pattern nanofibers on 2D and 3D substrates. A unique polymer ink formulation provides the right balance of viscosity and elasticity necessary to enable controlled, seamless near-field electrospinning of nanofibers at very low voltages. (more...)

The process developed involves the generation of human choroid plexus epithelial cells from human embryonic stem cells to enable novel clinical applications. (more...)

The current technology generally relates to systems and devices (e.g., bioreactors) used for collecting and accurately quantifying trace amounts of volatile organic gases (VOCs) obtained from the headspace above cell cultures. (more...)

Surface patterning for single-cell culture is of great importance in studies dealing with cell shape and microenvironment effects on the motility, migration, proliferation, and differentiation of cells.  These patterning techniques are key to effective cell printing needed for future medical advancements, such as 3D printing of artificial organs, tissue regeneration, and tissue engineering.  Despite advances in surface patterning methods, important material surfaces such as glass cannot be easily patterned with established printing methods without prior surface modification. Investigators at University of California at Berkeley have addressed this need by developing a single-cell patterning technique.  This innovation is accomplished by coating the substrate surface with a hydrophobic film and then patterning the film surface.  This surface patterning innovation for single-cell culture was achieved by combining plasma-assisted surface chemical modification, soft lithography, and protein-induced surface activation on glass.  In a proof of concept study, the investigators have accomplished surfaces seeding with mesenchymal stem cells in serum medium, resulting in single-cell patterning.   In additional research, using a dry lithography method, hydrophilic surface patterns on polystyrene were directly applied to cell culture dishes without the requirement of clean-room facilities or chemicals that could be harmful to sensitive cells. The long-term stability of single-cell patterns on PS dish surfaces produced by the present method was accomplished in cell culture experiments with neuron stem cells (NSCs) and bovine aorta endothelial cells. (more...)

Researchers at the University of California, Irvine have developed a microfluidic device that has a combination of side wall and planar electrodes designed to generate magnetohydrodynamics (MHD) and dielectrophoresis (DEP) forces on cells in solution. The MHD and DEP forces can separate a heterogeneous population of cells based on their different dielectric properties and sizes. (more...)

This work consists of a series of derived mathematical equations that describe the distribution of gas and pulmonary perfusion in various physiological states. These equations calculate intrathoracic pressure with various lung conditions (varying maximum volume, compliance, and baseline pressures) and the manipulation of ventilator settings (tidal volume, PEEP, and ventilation rate). The equations also integrate PaCO2 and PetCO2 as a function of pulmonary perfusion, as well as airflow through the lung, based on values obtained in a population of ED patients with and without obstructive lung disease. (more...)

Researchers at UC San Diego have created a new low-cost virtual reality device allowing users to ‘feel’ 3D images. The heads-up virtual reality (HUVR) device couples a 3D HDTV panel with a half-silvered mirror to project graphic images onto the user’s hands and/or into the space surrounding them. Head position is tracked to generate the correct perspective view, while the user maneuvers a haptic device to interact with the generated image, allowing users to ‘touch’ the image’s angles and contours, as if it was a tangible three-dimensional object. (more...)

Researchers at the University of California, Irvine have developed a simple method for the rapid self-assembly of predictable high density droplet-reactor arrays for high throughput microfluidic applications in biology and chemistry. By controlling the ratio of the chamber height to droplet diameter, the resulting self-assembled 3D colloidal, lattice droplet pattern formations can be selectively tuned for optimal real-time and/or long-term 2D visualization and image capture of reactions occuring in the droplet micro-reactors. (more...)

Electrochemical DNA biosensors are simple, inexpensive, and portable, making them attractive for decentralized genetic testing. Surface chemistry plays a major role in the overall performance of such biosensors. In particular, surface chemistry and coverage control is essential for assuring high reactivity, orientation/accessibility, and stability, while avoiding nonspecific adsorption and related background contributions. Several schemes for attaching nucleic acid probes to electrode surfaces and controlling the surface chemistry have thus been developed. Alkanethiol self-assembled monolayer (SAM) methods have been particularly useful for preparing reproducible probe-modified surfaces with high hybridization efficiency. Most often, two-component SAM monolayers of thiol-derivatized single-stranded oligonucleotide probe (thiolated capture probe, SHCP) and a short-chain 6-mercapto-1-hexanol (MCH) are used. Yet, such binary monolayers still suffer from background contributions and irreproducibility problems resulting from incomplete backfilling and surface defects. (more...)

Researchers at the University of California, Irvine have developed a Laplace pressure trap that can fuse droplets from different inlets and fuse droplets generated at different frequencies. The device traps and fuses droplets passively by balancing the driving hydrostatic pressure with increasing Laplace pressure imposed by the device’s design geometry. Above are video frames showing the Laplace pressure trap and of a single droplet fusion event at the Laplace trap. Frame A - Reference droplet can be seen waiting for its fusion partner. Excess partner droplets can be seen exiting towards the outlet. Frames B and C show the reference droplet and its fusion partner fuse and move toward the outlet. Frame D shows the next reference droplet approaching the trap. (more...)

Researchers at the University of California, Irvine (UCI) have developed a device that improves the efficiency of loading cells into microfluidic devices. (more...)

An interdisciplinary team of researchers has developed a microfluidics platform that uses electrophysiological signatures to sort living cells by their functionality. Because this method does not use exogenous labels, the purified cells are compatible with clinical translation. This includes a range of electrically-excitable cells, such as cardiomyocytes, neurons, and smooth muscle cells. This technology represents a new approach to cell sorting that does not rely on physical markers or protein expression profile. The platform is aimed at generating highly-pure populations of electrically active cells from heterogeneous stem cell progeny which is particular useful for regenerative medicine and tissue engineering, with additional applications in drug screening and basic research. Stage of Research The inventors have built a prototype device and used it to purify induced pluripotent stem cell (iPSC) cardiomyocytes from undifferentiated iPSC clusters. (more...)

A novel system and methods that provides efficient display and screening of peptide libraries at the cell surface, and enables rapid and quantitative characterization of the candidate peptides. (more...)

A new platform to mimic the in-vivo formation of angiogenesis. (more...)

Researchers at UC Berkeley have developed a synthetic polymer interface for the long-term self-renewal of human embryonic stem cells (hESCs) in defined media. Current culture systems for hESCs require the use of isolated animal derived extracellular matrix proteins or mouse embryonic feeder cells. The proposed use of a completely synthetic cell culture substrate avoids the problems associated with the variability of and the exposure to animal products. The hydrogel network coating is comprised of aminopropylmethacrylamide (APMAAm) monomer and N,N-methylenebis(acrylamide) (bis) crosslinker that was grafted to standard tissue culture polystyrene (TCPS) dishes via photoinitiated addition polymerization. Results for hESC proliferation and pluripotency markers were both qualitatively and quantitatively similar to cells cultured on MatrigelÔ -coated substrates.   (more...)

For producing RNA viruses, applications such as drug screening or basic research require immortalized tissue cultures that enable efficient production of fully infectious viruses of a genotype of clinical interest and are easy to use. In the case of hepatitis C virus (HCV), however, existing tissue culture systems yield incompletely replicated viruses (which do not infect cells in vitro), work only transiently, or are not robust enough and otherwise yield viruses with less prevalent HCV genotypes such as genotype 2. Thus, there is a need for a continuous or semi-continuous HCV production system that overcomes these limitations with the generation of a fully infectious HCV of genotype 1. (more...)

Researchers at the University of California, Irvine have developed a centrifugal microfluidic device with removable modular components. The use of these modular components gives the user flexibility to assemble his or her own fluidic system with standard modules that are connected with unique fluidic connectors. (more...)

In the areas of diagnostic and discovery applications surface bioaffinity sensing using either SPR sensors or LSPR sensors is currently being used for the detection of proteins, antibodies and nucleic acids. By combining the advantages of both SPR and LSPR, researchers at UCI have developed Nanoparticle-Enhanced Diffractions Grating biosensors (NEDG) that are able to detect unmodified DNA at a concentration of 10fM. (more...)

Researchers at the University of California, Irvine have developed a self-venting centrifugal microfluidic CD platform that mechanically lyses and homogenizes biological samples; after this sample processing, the purified NAs are then extracted on the same system and then run on a microarray that is also on the platform. (more...)

Determining oxygen levels in tumors is critical for advancing cancer diagnosis and therapy. A detailed knowledge of real-time changes in oxygen gradients within a tumor can assist in the profiling of tumor growth and improve the effectiveness of current treatment strategies, which function optimally at different oxygen concentrations. Small molecule luminescence has been suggested as a low cost, non-invasive alternative to traditional methods for sensing oxygen levels that are invasive, expensive, and/or lack sufficient spatio-temporal resolution to monitor real-time changes. In addition to sensing oxygen in tumors, luminescent small molecules, such as porphyrins, have been used for photodynamic therapy (PDT) to treat certain cancers by sensitizing oxygen for the production of cytotoxic reactive oxygen species (ROS). However, the utility of porphyrins has been hampered by low biocompatibility, lack of targetable delivery, and limited photophysical properties. The current invention describes a method for incorporating emissive porphyrins into proteins that offers a novel platform to enhance both oxygen sensing capabilities and targeted delivery to tumors. The bioluminescent proteins described not only have promising photophysical properties for biological use, but also are readily modifiable, biocompatible, and biostable. (more...)

This invention relates to the areas of the biochemical and chemical analysis of molecules in cells, and in particular to an assay and method for measuring the activation of internal chemical activity of a plurality of proteins in a single cell, a population of cells, or portion of a cell. The activity of multiple proteins in a single living cell, portion of a cell or in a group of cells is simultaneously measured by introducing reporter molecules into the cell(s) or a portion thereof, chemically modifying the reporter(s) by the enzyme of interest, terminating the modification reactions, removing the reporter(s) and modified reporter(s), and determining the amount of enzyme activity present by measuring or comparing the amount of reporter(s) and modified reporter(s) present. By performing a series of experiments at different time points, conditions, and varieties of cell types, a database is developed for molecular cellular mechanisms in health and disease states. By exposing cells to a variety of compounds data for drug development and screening is provided. (more...)

UCLA investigators have characterized an association between the expression of a single gene and behavioral learning associated with forebrain function. The gene is preferentially expressed in the cell bodies and dendrites of post-natal neurons of the forebrain. Since the geneis not expressed until after birth, it does not appear to be involved in development. To assess the physiological role of the gene, knockout (genedisruption) mice were developed. The null mice appear normal and reproduce normally, but show enhanced amygdala-dependent long-term memory consolidation with a concomitant elevation in amygdala, but not hippocampal, long-term potentiation (LTP). Hippocampal-dependent learning and motorskills appear normal, but mutant mice showed specific enhancement ofamygdala-dependent learning of fear as assessed by cued (tone) conditioning and taste aversion protocols. These findings represent a rare instance of elevated learning and memorythat is localized and experimentally accessible to both in vitro and in vivo analyses, and is the only such case associated with fear and emotion learning. Mutations of this gene may be a contributing factor in human neuropsychiatric disorders characterized by increased excitatory activity inthe amygdala or in amygdala dependent circuits. This gene, and reagents developed from it, should provide a useful model system for the development of therapeutic interventions. (more...)

TCL1 is a protooncogene overexpressed in many mature B cell lymphomas. TCL1 is also expressed in precursor T cells and absent by the CD4+ CD8+ stage of thymocyte development. In B cells, TCL1 is first expressed in pro-B cells, and is completely absent in memory B cells and plasma cells. (more...)

Progerias are rare genetic diseases characterized by premature aging including: retarded growth, osteoporosis, alopecia, and ultimately occlusive vascular disease. Many progeriod disorders are caused by mutations that lead to the accumulation of a lipid-modified form of prelamin A (farnesyl-prelamin A), resulting in a disruption of the cell nucleus. Zmpste24 is a mammalian integral membrane metalloproteinase that is critical for the processing of farnesylated proteins containing the carboxyl-terminal CAAX motif. Zmpste24, an ortholog of the yeast protein Ste24p, acts as an endoprotease by cleaving the 15 amino acids from the C terminus of prelamin A (including the farnesyl group), releasing mature lamin A. (more...)

The use of stem cells to treat a variety of degenerative diseases has been a promising area of research and treatment. However, the therapeutic use of stem cells depends on the availability of pluripotent cells that are not limited by technical, ethical, or immunological considerations. There have been research groups, including one at UCLA, that generated mouse iPS cells from fibroblast and demonstrated that these cells are functionally and molecularly virtually identical to embryonic stem cells. However, there is a need to generate human embryonic stem cells with human fibroblasts. (more...)

Researchers at UCLA have developed a C57Bl/6 based mouse model which lacks expression of a receptor for Type I Interferon (IFNAR). The animal lacks expression of the Type I receptor on all cells which has been shown to be the case genetically, biochemically and systemically in pathogen infection models. This is the first IFNAR KO mouse to be available on the C57Bl/6 background which is of most value to immunologists. (more...)

Acute liver failure or fulminant hepatic failure (FHF) represents a medical emergency and there are very limited large animal models for FHF to evaluate the efficacy of extracorporeal liver support devices in a pre-clinical setting. A model for FHF in pigs involving liver devascularization has previously been described by Benoist et. al. (2000), but the procedure for hepatic artery occlusion in these animals is difficult and not consistently reproducible. Further, incomplete occlusion in these animals can confound experimental results, leading to false positive outcomes. This is because complete occlusion to the liver is not easily verifiable. (more...)

Organizing and separating cells is a fundamental function in the research of biochemical systems. Cell separation methods that utilize electromagnetic forces in particular are useful in research applications, where magnetic beads can be linked with antibodies to ensure specific interaction with target cells. Conventional magnetic cell separator devices require multi-layered, complicated fabrication process to incorporate magnetic materials with the microfluidic channels. Furthermore, high magnetic field gradient are difficult to generate in microfluidic devices such as Micro Total Analysis Systems. The complexity and limitations of the current devices hinders increased utilization of cell separation techniques, prompting a need for a more economical design that would make high-yield separations more accessible to a variety of research applications. (more...)

Colon cancer is the third most common form of cancer in the United States. Therapy is usually invasive - surgery, followed by chemotherapy. Due to the lack of treatments that are effective for all cancer patients, there is a need to identify the patients that might benefit from specific anti-cancer drugs. Currently, dasatinib is approved to treat chronic myeloid leukemia (CML) and is in development to treat solid tumors, such as colon cancer. It would be useful to be able to predict the therapeutic effect of dasatinib and similar pharmaceuticals in individual colon cancer patients. (more...)

Many viral entry studies on highly pathogenic agents rely on cell-cell fusion and envelope pseudotyped reporter assays. These assays allow for detailed analyses of virus entry characteristics without high-level biosafety containment. Unfortunately, these surrogate assays may not fully emulate the biological properties of native envelope structures that are unique to the virus being studied. (more...)

Proteases or enzymes with proteolytic activity are fundamental to many key biological processes such as cell growth, cell death, blood clotting, matrix remodeling and immune defense. A large number of pathogens, including viruses, bacteria and multi-cellular parasites also use proteases to infect host cells, complete their life cycle and degrade the host immune system. Proteases have also been found to play a role in the pathogenesis of hypertension, liver cirrhosis, Alzheimers disease, autoimmune diseases, rheumatoid- or osteoarthritis and cancer. There is considerable effort to understand the role of proteases in disease and to identify therapeutic agents targeting specific protease activities. A bottleneck for high throughput drug screening, however, is now at the level of bioassays. Many compounds initially identified using in vitro assays fail in later phases of drug development because they cannot be used in a biologically relevant environment. Therefore, drug discovery researchers are now aggressively looking for high-throughput in vivo assays using cells, or, ideally, whole organisms, to screen potential drugs.What are needed are efficient bioassays to (1) determine the role of proteases in normal and diseased cellular processes and (2) screen in biologically meaningful systems for pharmacologic modulators of proteases of interest. (more...)

G protein-coupled receptor 4 (GPR4) has recently been identified as a novel proton-sensing receptor. GPR4 is expressed in vascular endothelial, smooth muscle, and several other cell types. UCLA researchers developed a GPR4 knockout mouse in order to better understand the in vivo role of GPR4 and investigate the hypothesis that GPR4 acts as a pH sensor in blood vessels. (more...)

For the first time a simple synthetic method to produce 8-fluoropurines has been developed at UCLA. Although there has been successful halogenation of the 8-position of purines with bromine, chlorine and iodine, electrophilic flourination of purines with elemental flourine are not known. As a result, access to 8- fluoropurines have been limited and very little is known about their biochemical and pharmacological properties. The advantages of UCLAs method are its simplicity and wider applicability. In general, fluorinated purines may find use in anti-cancer and anti-viral therapies. For example, we have evaluated the biological activity of 8-fluoroacycloguanines and have observed them to be functional substrates for HSV-tk. Extension of this electrophilic fluorination methodology to radiolabeling of purines with F-18 (a radioisotope of fluorine) has resulted in 8-[F-18] fluoropurines for use in Positron Emission Tomography (PET) in monitoring gene expression in-vivo. The commercial and scientific importance of this discovery is enormous. By following this general and broadly applicable methodology, it is now possible, for the first time, to synthesize otherwise inaccessible 8-fluoropurine derivatives. If you are interested in commercializing this patented technology, please contact the University for additional information. (more...)

Researchers at the University of California Berkeley have developed a new substrate for use in diagnostic biomolecular/protease testing, both in point-of-care and in clinical diagnostic lab setting. The technology provides an advance upon current colorimetric and flourometric hydrolytic activity assays, eliminating sensitive measurement equipment e.g. ELISA. Protease deviation from homeostatic behavior has been correlated to disease states e.g. rheumatoid arthritis, atherosclerosis, Alzheimer’s, stroke and cancer. This substrate holds the potential to revolutionize passive diagnostic tests such as pregnancy test and HIV lateral flow assays, in addition to advancing current hydrolysis assay technology. The substrate may provide for detection outside the biological world e.g. cocaine and lead. The substrate provides for a low-cost, portable tool that could expand the current testing capabilities of point-of-care diagnostic into protease activity monitoring. A hand held apparatus supporting the basic invention is thus also proposed to provide for a complete and ready to use innovation. (more...)

Brain development and aging, as well as neurological and psychiatric disorders are often associated with structural changes in the brain. Alzheimer’s Disease (AD) is one such neurological disorder, which afflicts up to 5.2 million people in the U.S. alone. Unfortunately, the diagnosis of AD relies on such limited tools as behavior monitoring and performance on standard neuropsychological tests. If therapy is to be maximally effective, AD needs to be correctly diagnosed as early as possible. (more...)

The present invention relates to a method for determining cancer susceptibility by quantifying DNA damage-induced mRNA in whole blood. (more...)

UC San Diego researchers have developed a new nanotechnology, smart dust, that has state-of-the-art applications in almost every field of use, including biological sensing, screening, and communications technology. The invention utilizes micron-sized particles of silicon that have been etched and then chemically modified in such a way that each individual particle has its own addressable identity. This feature allows one to use thousands of the particles together, each with its own “tag,” for high-sensitivity chemical or biological sensing, diagnostics, and low- and high-throughput screening of biomolecular compounds. (more...)

Most optical transducers for label-free biosensing involve measurement of a change in the refractive index of a material induced upon analyte binding. While surface plasmon resonance (SPR) films, resonant and nonresonant diffraction gratings, reflectometric interference (RIFS) layers and Fabry-Perot interferometers show very sensitive responses to small changes in refractive index, these methods are all limited by zero-point-drift arising from changes in temperature, matrix composition, or nonspecific binding to the analytical surface. A double-beam (Michelson-type) interferometer, in which one optical path acts as a reference channel, provides an excellent means of compensating for such effects. Various implementations of double-beam correction have been employed in micro-scale biosensor systems, generally involving two spatially distinct regions of a chip. However, because the sample and reference channels are separated in the X-Y plane, such designs pose significant alignment and manufacturability challenges, especially upon incorporation into high-throughput arrays. (more...)

Historically, metabolic networks have been studied in a piecemeal fashion using biochemical, then genomic and proteomic approaches. The abundance and complexity of data dwarfed the ability to understand and use the information in an intelligent and integrated fashion. The development of systems-level, computational approaches have provided new tools for extracting useful information from the morass. (more...)

An ultrathin silicon nitride membrane has been fabricated and tested to be useable in temperatures in excess of 1000 °C with mass flux rates several orders of magnitude greater than existing technlogies. Pore shape and size are also tunable. (more...)

University researchers have invented a powerful method for the molecular modeling of proteins. This invention can rapidly calculate the distribution of atomic neighbors. A primary advantage of this atomic density method is its computational efficiency, especially over previous generation method that use Fast Fourier Transforms. Software based on this algorithm can analyze molecular shape in seconds, while other methods may take minutes or hours. This algorithm can be used to deduce surface shape features, such as crevices and protrusions. It can also do detailed analysis of shape complementarity for docked complexes. The ability to determine regions of strong shape match or mismatch in an interface is very useful to computer-aided drug design. In addition to research, atomic density methods offer an ideal tool for learning about the shape features of molecules. The basic ideas underlying density methods can be understood intuitively, and integration within existing packages for molecular visualization would be a great aid to the study of protein structure-function relationships.. (more...)

Researchers at the University of California, Irvine, have developed a method for the computational optimization of DNA sequences that encode their own correct self-assembly. (more...)

Various methods exist for the quantification of disease related biomarkers; however, measurement of enzyme activity could be a better indicator of certain disease states when those disease states are caused by the activity of particular enzymes.  Proteases are enzymes that cleave proteins and account for approximately two percent of all proteins in humans.  Dysregulation of protease activity has been linked to a wide range of diseases including cancer and heart disease.  A new method of measuring protease activity and inhibition has been developed through the use of microcantilevers, which are nanomechanical transducers that convert intermolecular reaction forces into measurable cantilever deflections measured by optical methods.  Studies using a model protease (Trypsin) have shown that microcantilever arrays can measure protease activity over a varying substrate concentration and can measure inhibition of protease activity.  These devices and methods could be useful for measuring protease-substrate interactions, protease-substrate turnover, and for identifying protease inhibitors. (more...)

Systemic Lupus Erythematosus is an autoimmune disease which affects many organs and has a wide range of clinical manifestations. The disease is characterized by joint pain, rashes, and fevers, as well as inflammation of organs including the heart, lungs and kidneys. The cause of lupus has been difficult to identify, as almost every pathway of the immune system is abnormal in effected individuals. The production of auto-antibodies is thought to be largely responsible for the observed pathology; however, there is recent evidence that T lymphocytes promote and mediate the progression of the disease. (more...)

Researchers at UCSF have developed new C. albicans strains that use different auxotrophic markers that do not affect the virulence of C. albicans in a mouse model. Furthermore, these researchers have cloned complementing markers to be used in selection of knockout mutants from Candida strains other than C. albicans, thereby greatly reducing misintegration of DNA gene disruption fragments into the Candida auxotrophic marker site instead of the knockout target site. Combining these strains and markers with a fusion PCR technique allows for quick and efficient disruption of both alleles of the target gene in C. albicans. Generating homozygous knockouts is improved from 2% to 70% efficiency for knocking out the more difficult second allele. (more...)

The number of murine models for human cancer has grown rapidly in recent years and there now exist mouse models for almost all tumor types. Evaluating the effect of specific molecular alterations or therapeutic interventions in these animal models requires the ability to temporally and spatially assess the tumor burden. In many cases, however, this entails sacrificing the animal thereby limiting ability to perform follow up analysis, and necessitating the use of many more experimental animals. To address these problems, UCSF investigators have generated a general tumor reporter transgenic mouse strain designed to selectively expresses firefly luciferase in malignant tissue. (more...)

Candida albicans is one of the most frequently encountered fungal pathogens, causing a wide variety of infections ranging from mucosal infections in healthy immunocompetent people to life-threatening systemic infections in immunocompromised individuals such as those with AIDS and those undergoing immunosuppressive therapy or chemotherapy. When individuals with compromised immune system are infected, it is fatal in nearly one in three cases. The limited number of safe and effective antifungal drugs underscores the importance of understanding the genetic pathways underlying the pathogenicity of C. albicans.Because it is diploid and lacks a well-characterized sexual cycle, C. albicans poses a challenge for genetic analysis. UCSF researchers have recently carried out a genome-wide insertional mutagenesis of C. albicans. They have generated a library that represents one of the largest collections of mutant C. albicans, approximately 20,000 strains, each with an independent Tn7-based transposon insertion. There is an average of one insertion per 2.5kb of haploid genome.This library has been validated in a genetic screen that identified 300 genes, the haploinsufficieny of which affect the transition between single cell and filamentous growth, a feature of C. albicans associated with pathogenicity. Six of the genes identified were previously known to affect filamentous growth in C. albicans, validating the approach and suggesting that the library will prove useful for screening of genes associated with other functions. (more...)

Benign prostate hyperplasia (BPH) is the most common symptomatic neoplastic condition and malignant prostate cancer is the second leading cause of death among men. Yet the biological and molecular characteristics of these diseases remain poorly understood. In vitro and in vivo models of human prostate epithelial cells provide a useful model for the analyses of molecular and genetic mechanisms underlying prostate carcinogenesis. UCSF investigators have developed several immortalized and malignant adult human prostatic epithelial cell lines. (more...)

Membrane type serine protease 1 (MT-SP1), or matriptase, is a serine protease that is over-expressed on the surface of epithelial cells involved in a variety of cancers, including breast, colon and prostate. UCSF inventors have developed a novel antibody inhibitor of MT-SP1 (A11) which gains potency and specificity through interactions with the protease surface loops and binds in the active site in a catalytically non-competent manner.  The A11 antibody has applications as a therapeutic, diagnostic, and research tool. (more...)

BACKGROUND: Vaccine targets for prostate cancer have generally been identified either by tissue specific expression in prostate cancer or by assessing immune responses in cancer patients. However, UCSF investigators have taken a novel approach to identify the targets of an immune response in patients who are either responding or not responding to an immune-based treatment (anti-CTLA4 antibody) in a clinical trial at UCSF. CTLA4 blockade with antibody treatment can augment endogenous anti-tumor immunity in animal models and is being developed as an immunotherapy for cancer patients. Defining the antigen-specific responses induced by this treatment can lead to immunological identification of therapeutic targets that may be relevant in prostate cancer patients. These studies provide a unique opportunity to determine the antigen-specific responses that are relevant for immune-mediated clinical responses in prostate cancer, can provide opportunities to predict which patients may respond to therapy, and can provide novel approaches to prostate cancer treatment and vaccination. DESCRIPTION: UCSF investigators found that immune-mediated clinical responses to CTLA4 blockade is seen in the absence of a specific vaccination, suggesting that endogenous antigen-specific immune responses can be potentiated through this treatment. By focusing on immune responses unique to those patients that responded to immunotherapy, the UCSF investigators were able to identify candidate antigens that correlated with clinical outcome in prostate cancer patients. In addition, a patient’s immune response to the prostate cancer-associated antigens can be used as a diagnostic assay to determine the likelihood that an individual having prostate cancer will exhibit a clinically beneficial response to an immunomodulatory treatment. Furthermore, targeting these antigens with antibodies and/or vaccination may lead to novel therapies for prostate cancer. One antigen in particular has shown promise because it is expressed at a higher intensity in prostate cancer patients and in prostate cancer cell lines compared to other previously described antigens. Kaplan-Meier survival curves for tumor challenge were plotted for C57BL/6 and FVB mice (5 control and 5 test mice per mouse model) that were immunized with a mouse homolog of the particular antigen. The mice were challenged with Tramp cells or Myc-Cap prostate cancer cells respectively. Immunization with the novel antigen induced anti-tumor responses in both models of prostate cancer. (more...)

Gene therapy via viral vector technology has been associated with dangerous complications and risks. UCSF investigators have discovered a process that permits defective genetic sequences to be replaced with greater efficiency and potentially fewer side effects. The process, small fragment homologous replacement (SFHR), allows genes to be repaired in a site specific fashion and does not require the insertion of new genetic material into the genome. Thus, the SFHR approach should be applicable to a wide variety of gene therapy applications requiring the repair of specific mutations in DNA sequence. Furthermore, assay methods have been developed to monitor and quantify gene targeting frequency and to differentiate between cells carrying modified and unmodified DNA. (more...)

Hepatocellular carcinoma (HCC) is the most common form of liver cancer worldwide and accounts for three out of every four cases of primary liver cancer. HCC is the fifth most common cancer worldwide with a global incidence of one million cases each year. Although less common in the US than Asia and Africa, where HCC is the most common cancer in some countries, global incidence is increasing with the US having a three-fold increase in the last decade. This trend is especially alarming due to the poor prognosis associated with HCC. The overall five-year relative survival rate from liver cancer is about 7%, with the only curative options being surgery or liver transplantation. Alternative treatments include embolization, radiation therapy, and chemotherapy; however, liver cancer does not respond favorably to most currently available chemotherapeutic agents and doxorubicin and cisplatin remain the most effective agents. The increasing incidence of HCC, poor survival rate, and lack of treatment options necessitate the development of better treatments for HCC. A mouse model of HCC has been created, and validated, which closely mimics the development of HCC in patients and will be an important tool for the development of new therapeutics. (more...)

Alertness and general physical and mental performance are impaired during normal sleep periods compared to those during normal waking periods. Unlike stimulants such as caffeine or methamphetamine, certain glutamatergic enhancer compounds have been shown to improve memory and performace in tests conducted during normal sleep periods for both rats and humans. (more...)

This invention is an animal model and various cell-based models to determine nociception, pain transduction, and pain threshold. Researchers at the University of California, Irvine, discovered that overexpression of voltage-gated calcium channel alpha-2-delta-l subunit in neural tissue, and especially increased expression in spinal cord and dorsal root ganglia in transgenic mice, correlates in vivo with typical nerve injury-induced nociceptive responses to innocuous mechanical and thermal stimulation (tactile allodynia and thermal hyperalgesia). Significantly, such transgenic animals can be used to investigate nerve injury-induced neuropathic pain without inflicting nerve injury to the animals, which often interferes with test results. Similarly, neural cells obtained from such transgenic animals or neural cells transformed by overexpressing the alpha-2-delta-l subunit exhibit physiological parameters remarkably similar to those of neural tissue obtained from animals thought to have nerve injury-induced neuropathic pain. (more...)

Electrophoresis, the movement of charge particles in an electric field, is commonly used in chemistry, biology and medicine to separate macromolecules including DNA and RNA. Bulk gel and capillary electrophoresis are among the two most widely used electrophoretic methods. However, the bulk method has slow separation times and while the capillary method has faster separation times (and higher resolution) its costs are much higher due to an increase in ancillary equipment and corresponding fabrication costs. To address those weaknesses and tradeoffs, researchers at UC Berkeley have developed a new electrophoretic method with low-cost fabrication attributes that involve photolithography, micro-imprinting or wet lithography. The advantages that this novel Berkeley method has over bulk gel and capillary electrophoresis include (1) easy analyte extraction, (2) minimal ancillary equipment, and (3) simultaneous multiple assay capabilities. This new method has additional advantages over the bulk gel method including (1) reduced assay time, (2) higher resolutions, (3) reduced sample size, and (4) smaller form-factor. (more...)

DNase II, an endonuclease, has recently been shown to play a role in many different cellular activities. Mammalian DNase II enzymes and the Caenorhabditis elegans homolog NUC-1 have been shown to be critically important during engulfment-mediated clearance of apoptotic DNA. NUC-1 has been demonstrated to participate in apoptotic DNA degradation in nematodes while the mammalian enzyme appears to be critical for full degradation of engulfed apoptotic DNA. Both DNase I and DNase II have also been implicated in tumor cell necrosis induced by specific vitamin regimens. Furthermore, DNase II has been observed to play a major role in chromatin cleavage during terminal differentiation in lens cells. Finally, DNase II has been implicated by researchers at the University of California in isotype switch recombination; the process of varying antibody isotypes by targeted rearrangement of the antibody genes in mature B cells. (more...)