Abstract: The present invention provides compositions comprising cells that can effectively produce HCV after HCV infection, compositions for culturing the cells, methods for making the composition and methods for infecting the cells in the composition with HCV. The present invention also provides methods for assaying HCV production and methods for evaluating compounds that affect the production of HCV.

Abstract: The invention discloses the sequences of variant forms of alpha-fetoprotein transcripts that have been identified in human hemopoietic progenitors but not in differentiated mature cells. The variant forms of AFP (vAFP) cDNA sequences isolated from a multipotent hemopoietic cell line, K562, differ from the authentic AFP transcript, consisting of 15 exons, by lacking only exon 1. Instead of exon 1, vAFP transcripts use an additional one or two exons located in the 5?-untranslated region of the AFP gene. K562 expressed selectively vAFP, whereas a hepatocellular carcinoma cell line, HepG2, showed no detectable expression of vAFP. In normal adult tissues, vAFP transcripts is detected in the bone marrow, thymus and brain, but not the spleen, suggesting the expression occurs in normal hemopoietic progenitors. Moreover, CD34+Lin? hemopoietic stem/progenitor cells purified by flow cytometric sorting also express the variant transcripts.

Abstract: The present invention relates to precursor cells to hepatic stellate cells, compositions comprising same and methods of isolating same. The surface antigenic profile of the precursors is MHC class Ia negative, ICAM-1+, VCAM-1+, ?3-integrin+. In addition to expression of these surface markers, the cells also express the intracellular markers desmin, vimentin, smooth muscle ?-actin, nestin, hepatocyte growth factor, stromal derived factor-1? and Hlx homeobox transcriptional factor.

Abstract: A method of repairing diseased or dysfunctional organs or of establishing a model system of a disease state is provided. For repairing diseased organs, the method involves engraftment of cells from healthy tissue of the diseased or dysfunctional organ admixed with gel-forming biomaterials and nutrient medium, signaling molecules and extracellular matrix components that can be made insoluble rapidly upon transplantation to form a graft. In this way, the graft mimics the complexity of the native microenvironment with a minimum number of components that allow transplantation of cells to successfully engraft, expand and then rebuild part or the entirety of the diseased or dysfunctional organ. In the case of using grafting methods for establishing a disease model, diseased cells may be transplanted in the biomaterials and into experimental hosts.

Abstract: The present invention provides compositions comprising cells that can effectively produce HCV after HCV infection, compositions for culturing the cells, methods for making the composition and methods for infecting the cells in the composition with HCV. The present invention also provides methods for assaying HCV production and methods for evaluating compounds that affect the production of HCV.

Abstract: The present invention relates to a multipotent stem cell, multipotent cell populations, and an enriched multipotent cell population, each found in fetal, neonatal, pediatric, and adult biliary tree tissue and up to 72 hours post mortem (although preferentially, within 10 hours post mortem) and capable of maturing into multiple endodermal tissues that include liver, biliary and pancreatic tissues. The multipotent stem/progenitor cell and cell populations are found in peribiliary glands, and progenitors descending from them are present throughout the biliary tree including in the gallbladder. High numbers of the peribiliary glands are found in the branching locations of the biliary tree such as hilum, common hepatic duct, cystic duct, common duct, common hepato-pancreatic duct and gallbladder. Related multipotent cells, multipotent cell populations and their descendent progenitors are found throughout the biliary tree including in the gall bladder, which does not have peribiliary glands.

Abstract: A method is provided for controlling the survival, proliferation, and/or differentiation of hepatic progenitors in vitro by using specific types of mesenchymal feeder cells or one of more of the paracrine signals produced by those feeders.

Abstract: The present invention provides compositions comprising cells that can effectively produce HCV after HCV infection, compositions for culturing the cells, methods for making the composition and methods for infecting the cells in the composition with HCV. The present invention also provides methods for assaying HCV production and methods for evaluating compounds that affect the production of HCV.

Abstract: The present invention relates to precursor cells to hepatic stellate cells, compositions comprising same and methods of isolating same. The surface antigenic profile of the precursors is MHC class Ia negative, ICAM-1+, VCAM-1+, ?3-integrin+. In addition to expression of these surface markers, the cells also express the intracellular markers desmin, vimentin, smooth muscle ?-actin, nestin, hepatocyte growth factor, stromal derived factor-1? and H1x homeobox transcriptional factor.

Abstract: The instant invention provides, for the first time, the use of cadaveric organs from donors with non-beating hearts as a source of functional cells such as progenitor or stem cells for various medical purposes. More specifically, a method is disclosed whereby a tissue source of progenitor cells is obtained comprising harvesting tissue from a donor, wherein the donor has a non-beating heart for as long as about thirty hours postmortem and processing the cadaveric tissue to provide progenitor cells. The instant progenitors are used for various medical purposes as means of cell therapy, gene therapy, artificial organs, bioreactors, organ regeneration and the like.

Abstract: Methods of isolating and cryopreserving progenitors from human liver are disclosed which include processing human liver tissue to provide a substantially single cell suspension comprising progenitors and non-progenitors of one or more cell lineages found in human liver; subjecting the suspension to a debulking step, which reduces substantially the number of non-progenitors in the suspension, and which provides a debulked suspension enriched in progenitors exhibiting one or more markers associated with at least one of the one or more cell lineages; and selecting from said debulked suspension those cells, which themselves, their progeny, or more mature forms thereof express one or more markers associated with at least one of the one or more cell lineages. Among these markers are CD14, CD34, CD38, CD45, and ICAM. Hepatic progenitors are characterized as being 6-15? in diameter, diploid, glycophorin A?, CD45?, AFP+++, ALB+, ICAM+, and with subpopulations varying in expression of CD14+. CD34++, CD38++, CD117+.

Abstract: A composition which comprises an animal cell population which contains immature animal cells. The immature animal cells are characterized by expression of alpha-fetoprotein or lack of essential expression of alpha-fetoprotein and albumin, and at least a portion of said immature animal cells or at least a portion of the progeny of said immature animal cells is capable of differentiating into cells which express albumin. The cell population is cultured under conditions which result in expansion of the cells. Expansion of the cells may be achieved by culturing the cells in the presence of an extracellular matrix and liver stromal cells; and preferably in the presence of growth factors. Such cells may be used for liver transplantation, artificial livers, and for toxicology and pharmacology studies. Such cells may also be genetically engineered to express proteins or polypepetides of interest.

Abstract: The present invention is directed toward a method for obtaining from whole liver or a resection thereof a population of cells comprising viable, functional liver cells enriched in hepatocytes and hepatocyte stem/progenitor cells, compositions thereof, and uses therefore. Compositions include a composition of liver cells enriched in hepatocytes and hepatocyte stem/progenitor cells and a pharmaceutical composition thereof. Uses include treatment of liver diseases, regeneration of liver, toxicity testing, and liver assist devices.

Abstract: A method is provided of propagating hepatic progenitors in vitro on or in one or multiple extracellular matrix components found in the stem cell compartment or niche of liver. A container for the propagation of the progenitors and comprising culture dishes, bioreactors, or lab chips.

Abstract: A method of obtaining a mixture of cells enriched in hepatic progenitors is developed which comprises methods yielding suspensions of a mixture of cell types, and selecting those cells that are classical MHC class I antigen(s) negative and ICAM-1 antigen positive. The weak or dull expression of nonclassical MHC class I antigen(s) can be used for further enrichment of hepatic progenitors. Furthermore, the progenitors can be selected to have a level of side scatter, a measure of granularity or cytoplasmic droplets, that is higher than that in non-parenchymal cells, such as hemopoietic cells, and lower than that in mature parenchymal cells, such as hepatocytes. Furthermore, the progeny of the isolated progenitors can express alpha-fetoprotein and/or albumin and/or CK19. The hepatic progenitors, so isolated, can grow clonally, that is an entire population of progeny can be derived from one cell. The clones of progenitors have a growth pattern in culture of piled-up aggregates or clusters.

Abstract: A method of obtaining a mixture of cells enriched in hepatic progenitors is developed which comprises methods yielding suspensions of a mixture of cell types, and selecting those cells that are classical MHC class I antigen(s) negative and ICAM-1 antigen positive. The weak or dull expression of nonclassical MHC class I antigen(s) can be used for further enrichment of hepatic progenitors. Furthermore, the progenitors can be selected to have a level of side scatter, a measure of granularity or cytoplasmic droplets, that is higher than that in non-parenchymal cells, such as hemopoietic cells, and lower than that in mature parenchymal cells, such as hepatocytes. Furthermore, the progeny of the isolated progenitors can express alpha-fetoprotein and/or albumin and/or CK19. The hepatic progenitors, so isolated, can grow clonally, that is an entire population of progeny can be derived from one cell. The clones of progenitors have a growth pattern in culture of piled-up aggregates or clusters.

Abstract: A method of propagating mammalian endodermally derived progenitors such as hepatic progenitors, their progeny, or mixtures thereof is developed which includes culturing mammalian progenitors, their progeny, or mixtures thereof on a layer of embryonic mammalian feeder cells in a culture medium. The culture medium can be supplemented with one or more hormones and other growth agents. These hormones and other growth agents can include insulin, dexamethasone, transferrin, nicotinamide, serum albumin, ?-mercaptoethanol, free fatty acid, glutamine, CuSO4, and H2SeO3. The culture medium can also include antibiotics. Importantly, the culture medium does not include serum. The invention includes means of inducing the differentiation of the progenitors to their adult fates such as the differentiation of hepatic progenitor cells to hepatocytes or biliary cells by adding, or excluding epidermal growth factor, respectively.

Abstract: A method is provided for controlling the survival, proliferation, and/or differentiation of hepatic progenitors in vitro by using specific types of mesenchymal feeder cells or one of more of the paracrine signals produced by those feeders.

Abstract: A bioreactor for three-dimensional culture of liver cells is disclosed. The device is characterized by the use of textile vasculatures. A model and method for optimizing vasculature parameters is also disclosed. Liver acinar structure and physiological parameters are mimicked by sandwiching cells in the space between the two innermost woven textile hollow fibers, and creating radial flow of media from an outer compartment, through the cell mass compartment, and to an inner compartment. The theoretical optimum hydraulic permeability for the two innermost semi-permeable membranes is determined based on physiological hepatic sinusoidal blood flow and pressures. Experimental studies using a flow rate and pressure monitoring systems in conjunction with phase-contrast velocity-encoded MRI confirm theoretical results. Novel woven vascular tubes with optimum hydraulic permeability are disclosed for culturing hepatocytes in the multi-coaxial bioreactor.

Abstract: A method of propagating mammalian endodermally derived progenitors such as hepatic progenitors, their progeny, or mixtures thereof is developed which includes culturing mammalian progenitors, their progeny, or mixtures thereof on a layer of embryonic mammalian feeder cells in a culture medium. The culture medium can be supplemented with one or more hormones and other growth agents. These hormones and other growth agents can include insulin, dexamethasone, transferrin, nicotinamide, serum albumin, ?-mercaptoethanol, free fatty acid, glutamine, CuSO4, and H2SeO3. The culture medium can also include antibiotics. Importantly, the culture medium does not include serum. The invention includes means of inducing the differentiation of the progenitors to their adult fates such as the differentiation of hepatic progenitor cells to hepatocytes or biliary cells by adding, or excluding epidermal growth factor, respectively.