4917results about "Embryonic cells" patented technology

Methods and materials for culturing primate-derived primordial stem cells are described. In one embodiment, a cell culture medium for growing primate-derived primordial stem cells in a substantially undifferentiated state is provided which includes a low osmotic pressure, low endotoxin basic medium that is effective to support the growth of primate-derived primordial stem cells. The basic medium is combined with a nutrient serum effective to support the growth of primate-derived primordial stem cells and a substrate selected from the group consisting of feeder cells and an extracellular matrix component derived from feeder cells. The medium further includes non-essential amino acids, an anti-oxidant, and a first growth factor selected from the group consisting of nucleosides and a pyruvate salt.

The present invention provides methods to promote the differentiation of pluripotent stem cells. In particular, the present invention provides an improved method for the formation of pancreatic endoderm, pancreatic hormone expressing cells and pancreatic hormone secreting cells. The present invention also provides methods to promote the differentiation of pluripotent stem cells without the use of a feeder cell layer.

Disclosed herein are cell cultures comprising PDX1-positive endoderm cells and methods of producing the same. Also disclosed herein are cell populations comprising substantially purified PDX1-positive endoderm cells as well as methods for enriching, isolating and purifying PDX1-positive endoderm cells from other cell types. Methods of identifying differentiation factors capable of promoting the differentiation of endoderm cells, such as PDX1-positive foregut endoderm cells and PDX1-negative definitive endoderm cells, are also disclosed.

Stem cells, including mammalian, and particularly primate primordial stem cells (pPSCs) such as human embryonic stem cells (hESCs), hold great promise for restoring cell, tissue, and organ function. However, cultivation of stem cells, particularly undifferentiated hESCs, in serum-free, feeder-free, and conditioned-medium-free conditions remains crucial for large-scale, uniform production of pluripotent cells for cell-based therapies, as well as for controlling conditions for efficiently directing their lineage-specific differentiation. This instant invention is based on the discovery of the formulation of minimal essential components necessary for maintaining the long-term growth of pPSCs, particularly undifferentiated hESCs. Basic fibroblast growth factor (bFGF), insulin, ascorbic acid, and laminin were identified to be both sufficient and necessary for maintaining hESCs in a healthy self-renewing undifferentiated state capable of both prolonged propagation and then directed differentiation. Having discerned these minimal molecular requirements, conditions that would permit the substitution of poorly-characterized and unspecified biological additives and substrates were derived and optimized with entirely defined constituents, providing a “biologics”-free (i.e., animal-, feeder-, serum-, and conditioned-medium-free) system for the efficient long-term cultivation of pPSCs, particularly pluripotent hESCs. Such culture systems allow the derivation and large-scale production of stem cells such as pPSCs, particularly pluripotent hESCs, in optimal yet well-defined biologics-free culture conditions from which they can be efficiently directed towards a lineage-specific differentiated fate in vitro, and thus are important, for instance, in connection with clinical applications based on stem cell therapy and in drug discovery processes.

The present invention provides cell populations that are enriched for mesendoderm and mesoderm, and cell populations that are enriched for endoderm. The cell populations of the invention are useful for generating cells for cell replacement therapy.

The present invention features novel placental derived stem cells and provides methods and compositions for the therapeutic uses of placental derived stem cells or placental derived stem cells that have been induced to differentiate into a desired tissue type into a recipient host in amounts sufficient to result in production of the desired cell type, i.e., hepatic, pancreatic, neuronal, or nervous tissue.

The present invention provides methods of modulating mammalian, particularly human, stem cell and progenitor cell differentiation to regulate and control the differentiation and maturation of these cells along specific cell and tissue lineages. The methods of the invention relate to the use of certain small organic molecules to modulate the differentiation of stem cell populations along specific cell and tissue lineages, particularly embryonic-like stem cells originating from a postpartum placenta or stem cells isolated form sources such as cord blood. The invention also relates to the treatment or prevention of myelodysplastic syndrome or myeloproliferative syndrome, or symptoms thereof, comprising administration of JNK or MKK inhibitors, alone or in combination, as well as with or without the use of unconditioned cells or cells conditioned in accordance with other aspects of the invention. Finally, the invention relates to the use of such differentiated stem cells in transplantation and other medical treatments.

A source of multipotent amniotic fluid / fetal stem cells (MAFSCs) is disclosed. MAFSC are of fetal origin and have a normal diploid karyotype. These cells are characterized by the following cell surface markers: SSEA3, SSEA4, Tra-1-60, Tra-1-81, Tra-2-54, HLA class I, CD13, CD44, CD49b, CD105 and are distinguished by the absence of the antigen markers CD34, CD45, and HLA Class II, but are distinguished from mouse embryonic stem cells in that these cells do not express the cell surface marker SSEA1. MAFSC express the stem cell transcription factor Oct-4. MAFSC cells can be propagated for an indefinite period of time in continuous culture in an undifferentiated state. The MAFSCs have the ability to differentiate in culture in a regulated manner, into three or more subphenotypes. Cells can then be differentiated into endodermal, mesodermal and ectodermal derived tissues in vitro and in vivo. A method for isolating, identifying, expanding and differentiating MAFSCs is disclosed.

The present invention provides improved compositions and methods for the collection of stem cells from an organ, e.g., placenta. The invention provides a stem cell collection composition comprising an apoptosis inhibitor and, optionally, an enzyme such as a protease or mucolytic enzyme, vasodilator, necrosis inhibitor, oxygen-carrying perfluorocarbon, or an organ preserving compound. The invention provides methods of using the stem cell collection composition to collect stem cells and to preserve populations of stem cells.

The present invention relates to methods of modulating mammalian stem cell and progenitor cell differentiation. The methods of the invention can be employed to regulate and control the differentiation and maturation of mammalian, particularly human stem cells along specific cell and tissue lineages. The methods of the invention relate to the use of certain small organic molecules to modulate the differentiation of stem or progenitor cell populations along specific cell and tissue lineages, and in particular, to the differentiation of embryonic-like stem cells originating from a postpartum placenta or for the differentiation of early progenitor cells to a granulocytic lineage. Finally, the invention relates to the use of such differentiated stem or progenitor cells in transplantation and other medical treatments.

Stem cells, including mammalian, and particularly primate primordial stem cells (pPSCs) such as human embryonic stem cells (hESCs), hold great promise for restoring cell, tissue, and organ function. However, cultivation of stem cells, particularly undifferentiated hESCs, in serum-free, feeder-free, and conditioned-medium-free conditions remains crucial for large-scale, uniform production of pluripotent cells for cell-based therapies, as well as for controlling conditions for efficiently directing their lineage-specific differentiation. This instant invention is based on the discovery of the formulation of minimal essential components necessary for maintaining the long-term growth of pPSCs, particularly undifferentiated hESCs. Basic fibroblast growth factor (bFGF), insulin, ascorbic acid, and laminin were identified to be both sufficient and necessary for maintaining hESCs in a healthy self-renewing undifferentiated state capable of both prolonged propagation and then directed differentiation. Having discerned these minimal molecular requirements, conditions that would permit the substitution of poorly-characterized and unspecified biological additives and substrates were derived and optimized with entirely defined constituents, providing a “biologics”-free (i.e., animal-, feeder-, serum-, and conditioned-medium-free) system for the efficient long-term cultivation of pPSCs, particularly pluripotent hESCs. Such culture systems allow the derivation and large-scale production of stem cells such as pPSCs, particularly pluripotent hESCs, in optimal yet well-defined biologics-free culture conditions from which they can be efficiently directed towards a lineage-specific differentiated fate in vitro, and thus are important, for instance, in connection with clinical applications based on stem cell therapy and in drug discovery processes.

The invention relates to methods for culturing human embryonic stem cells by culturing the stem cells in an environment essentially free of mammalian fetal serum and in a stem cell culture medium including amino acids, vitamins, salts, minerals, transferring, insulin, albumin, and a fibroblast growth factor that is supplied from a source other than just a feeder layer the medium. Also disclosed are compositions capable of supporting the culture and proliferation of human embryonic stem cells without the need for feeder cells or for exposure of the medium to feeder cells.

A method of increasing the growth of stem cells by mixing the stem cells with a growth medium that has been conditioned by an incubation with placental tissue. The method increases the expansion of the stem cell population.

The present invention provides fully human antibodies in a transgenic animal of a desired isotype in response to immunization with any virtually any desired antigen. The human immunoglobulin heavy chain transgene in the foregoing animals comprises a human constant region gene segment comprising exons encoding the desired heavy chain isotype, operably linked to switch segments from a constant region of a different heavy chain isotype, i.e., a non-cognate switch region. Said additional constant region segment comprises a switch region and human constant region coding segment, wherein the constant region coding segment is operably linked to a switch region that it is not normally associated with, i.e., a non-cognate switch region. In the transgenes of the invention, the non-cognate switch region may be a switch region from a different species than the constant region coding segment. The switch region and membrane exons of the invention may comprise a human gamma-2 constant region and the secreted constant region exons are from a human gamma-1 or a human gamma-4 constant region.

The present invention relates to a method for isolating stem / progenitor cells from the amniotic membrane of umbilical cord, wherein the method comprises separating the amniotic membrane from the other components of the umbilical cord in vitro, culturing the amniotic membrane tissue under conditions allowing cell proliferation, and isolating the stem / progenitor cells from the tissue cultures. The isolated stem cell cells can have embryonic stem cell-like properties and can be used for various therapeutic purposes. In one embodiment, the invention relates to the isolation and cultivation of stem cells such as epithelial and / or mesenchymal stem / progenitor cells under conditions allowing the cells to undergo mitotic expansion. Furthermore, the invention is directed to a method for the differentiation of the isolated stem / progenitor cells into epithelial and / or mesenchymal cells.

The invention relates to methods for culturing human embryonic stem cells by culturing the stem cells in an environment essentially free of mammalian fetal serum and in a stem cell culture medium including amino acids, vitamins, salts, minerals, transferring, insulin, albumin, and a fibroblast growth factor that is supplied from a source other than just a feeder layer the medium. Also disclosed are compositions capable of supporting the culture and proliferation of human embryonic stem cells without the need for feeder cells or for exposure of the medium to feeder cells.

An improved method of nuclear transfer involving the transplantation of donor differentiated cell nuclei into enucleated oocytes of the same species as the donor cell is provided. The resultant nuclear transfer units are useful for multiplication of genotypes and transgenic genotypes by the production of fetuses and offspring, and for production of isogenic CICM cells, including human isogenic embryonic or stem cells. Production of genetically engineered or transgenic mammalian embryos, fetuses and offspring is facilitated by the present method since the differentiated cell source of the donor nuclei can be genetically modified and clonally propagated.

Previous methods for culturing human embryonic stem cells have required either fibroblast feeder cells or a medium which has been exposed to fibroblast feeder cells in order to maintain the stem cells in an undifferentiated state. It has now been found that if high levels of fibroblast growth factor are used in a medium with gamma amino butyric acid, pipecholic acid, lithium and lipids, the stem cells will remain undifferentiated indefinitely through multiple passages, even without feeder cells or conditioned medium. A humanized matrix of human proteins can be used as a basement matrix to culture the cells. New lines of human embryonic stem cells made using these culture conditions, the medium and the matrix, will never have been exposed to animal cells, animal products, feeder cells or conditioned medium.

The present invention relates to methods for reprogramming a somatic cell to pluripotency by administering into the somatic cell at least one or a plurality of potency-determining factors. The invention also relates to pluripotent cell populations obtained using a reprogramming method.

The invention is directed to substantially purified amnion-derived cell populations, compositions comprising the substantially purified amnion-derived cell populations, and to methods of creating such substantially purified amnion-derived cell populations, as well as methods of use. The invention is further directed to antibodies, in particular, monoclonal antibodies, that bind to amnion-derived cells or, alternatively, to one or more amnion-derived cell surface protein markers. The invention is further directed to methods for producing the antibodies, methods for using the antibodies, and kits comprising the antibodies.

The present invention provides methods for culturing, expanding and differentiating stem cells, particularly human embryonic stem cells. The methods comprise culturing the stem cells for a period of time on a collagen biofabric, particularly a collagen biofabric derived from the amniotic membrane, chorion, or both, from mammalian placenta.

The invention describes improved methods and compositions for producing a recombinant protein, e.g., an antibody, in mammalian cell culture. In addition, the invention provides improved cell culture media, including improved production media, feed solutions, and combination feeds, which may be used to improve protein productivity in mammalian cell culture.

The present invention provides a non-mouse, including human, pluripotential embryonic stem cell which can:(a) be maintained on feeder layers for at least 20 passages; and(b) give rise to embryoid bodies and multiple differentiated cell phenotypes in monolayer culture.The invention further provides a method of making a pluripotential embryonic stem cell comprising culturing germ cells and germ cell progenitors in a composition comprising a growth enhancing amount of basic fibroblast growth factor, leukemia inhibitory factor, membrane associated steel factor, and soluble steel factor to primordial germ cells under cell growth conditions, thereby making a pluripotential embryonic stem cell.Also provided are compositions useful to produce the pluripotent embryonic stem cells and methods of screening associated with the method of making the embryonic stem cell.

Cells derived from postpartum placenta and methods for their isolation are provided by the invention. The invention further provides cultures and compositions of the placenta-derived cells. The placenta-derived cells of the invention have a plethora of uses, including but not limited to research, diagnostic, and therapeutic applications.

Cells derived from postpartum tissue such as the umbilical cord and placenta, and methods for their use to regenerate, repair, and improve neural tissue, and to improve behavior and neurological function in stroke patients are disclosed.

The present invention provides methods and compositions for the production of glial cells and oligodendrocytes from placenta stem cells. The invention further provides for the use of these glia and oligodendrocytes in the treatment of, and intervention in, for example, trauma, ischemia and degenerative disorders of the central nervous system (CNS), particularly in the treatment of demyelinating diseases such as multiple sclerosis.

Disclosed herein are methods of identifying one or more differentiation factors that are useful for differentiating cells in a cell population comprising definitive endoderm cells into cells which are capable of forming tissues and / or organs that are derived from the gut tube.

A method for engineering and utilizing large DNA vectors to target, via homologous recombination, and modify, in any desirable fashion, endogenous genes and chromosomal loci in eukaryotic cells. These large DNA targeting vectors for eukaryotic cells, termed LTVECs, are derived from fragments of cloned genomic DNA larger than those typically used by other approaches intended to perform homologous targeting in eukaryotic cells. Also provided is a rapid and convenient method of detecting eukaryotic cells in which the LTVEC has correctly targeted and modified the desired endogenous genes(s) or chromosomal locus (loci) as well as the use of these cells to generate organisms bearing the genetic modification.