Provided is an isolated population of human pluripotent stem cells comprising at least 50% human pluripotent stem cells characterized by an OCT4+/TRA1-60?/TRA1-81?/SSEA1+/SSEA4? expression signature, and novel methods of generating and maintaining same in a pluripotent, undifferentiated state a suspension culture devoid of cell clumps. Also provided are novel culture media, cell cultures and methods for culturing pluripotent stem cells in a suspension culture or a two-dimensional culture system while maintaining the cells in a proliferative, pluripotent and undifferentiated state. The novel culture media comprise interleukin 11 (IL11) and Ciliay Neurotrophic Factor (CNTF); bFGF at a concentration of at least 50 ng/ml and an IL6RIL6 chimera; or an animal contaminant-free serum replacement and an IL6RIL6 chimera. Also provided are methods for generating lineage-specific cells from the pluripotent stem cells.

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.

Methods for preparing ex vivo T cell cultures using IL-21 compositions for use in adoptive immunotherapy are described. Addition of IL-21 to cultures of non-terminally differentiated T cells population, either isolated or present in peripheral blood mononuclear cells are exposed to one or more tumor antigens, and in the presence of IL-21 compositions and antigen presenting cells (APCs), the resulting T cell population has an enhanced antigen-specificity, and can be reintroduced into the patient. Methods are also disclosed for identifying tumor antigens by culturing T cell populations exposed to IL-21 compositions and APCs in the presence of tumor material.

Well-defined, xeno-free culture media which comprise a TGF-beta isoform or the chimera formed between IL6 and the soluble IL6 receptor (IL6RIL6), which are capable of maintaining stem cells, and particularly, human embryonic stem cells, in an undifferentiated state are provided. Also provided are cell cultures comprising the culture media and the stem cells and methods of expanding and deriving embryonic stem cells in such well-defined, xeno-free culture media. In addition, the present invention provides methods of differentiating ESCs or EBs formed therefrom for the generation of lineage specific cells.

The invention involves the discovery that if dendritic cells loaded with a tumor antigen are cultured in interleukin-15 (IL-15), or if T cells activated by the dendritic cells are cultured in IL-15, Treg activity that is specific for the tumor antigen is reduced. This reduction in Treg activity results in an increase in anti-tumor immune response. Another embodiment of the invention involves the discovery that incubating dendritic cells with a MAP kinase inhibitor in combination with IL-15 gives synergistic benefits when the dendritic cells are used to activate T cells. Dendritic cell and T cell compositions incubated with IL-15 or a MAP kinase inhibitor are provided.

The inventive subject matter relates to methods for treating a T-cell deficiency in a subject in need thereof, comprising administering to said subject a T-cell precursor isolated from an allogeneic donor, provided that said allogeneic donor is not MHC-matched to said subject. The inventive methods can be further enhanced by genetic engineering for targeted immunotherapy.

Certain embodiments of the invention are directed to methods for inducing an immunologic response to a tumor in a patient using mature dendritic cells transfected with a nucleic acid composition encoding one or more tumor antigens and loaded with a corresponding tumor antigen composition.

The present invention encompasses methods and compositions for the generation and use of cytotoxic T lymphocytes that target multiple viruses or that are specific for multiple tumor antigens. In specific embodiments, the generation methods employ use of certain cytokines to promote proliferation and reduce cell death in an activated T cell population and/or that employ a particular bioreactor having a gas permeable membrane.

Well-defined, xeno-free culture media which comprise a TGF-beta isoform or the chimera formed between IL6 and the soluble IL6 receptor (IL6RIL6), which are capable of maintaining stem cells, and particularly, human embryonic stem cells, in an undifferentiated state are provided. Also provided are cell cultures comprising the culture media and the stem cells and methods of expanding and deriving embryonic stem cells in such well-defined, xeno-free culture media. In addition, the present invention provides methods of differentiating ESCs or EBs formed therefrom for the generation of lineage specific cells.

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.