The nuclear reprogramming of somatic cells with mRNA encoding reprogramming factors is shown to be greatly accelerated by activation of innate immune responses in the somatic cell. Methods of activating innate immunity include activation of PKR, of toll-like receptors, e.g. TLR3, etc. In some embodiments the mRNA provides the activator of innate immunity.

An object of the present invention is to provide a medium that comprises fewer protein components and enables the maintenance of pluripotent stem cells in an undifferentiated state. The culture medium for pluripotent stem cells comprises a GSK3β inhibitor (A) and a DYRK inhibitor (B).

Reprogramming allows the “conversion” of any mature or somatic cell of the human or animal body into a pluripotent stem cell. Reprogramming can be performed through the introduction of exogenous factors, usually transcription factors, into the mature cell. This process allows the production of induced pluripotent stem cells without the use of embryos, with the advantage that they can be produced from an individual to return/re-implant to the same individual. The inventors have developed a method of transient expression of exogenous reprogramming factors using a transient vector, wherein the vector is a closed linear DNA. Surprisingly, pluripotent stem cells developed in this manner are stable and closer in phenotype to natural stem cells such as ESCs.

Method for expanding stemness and differentiation potential of pluripotent cells. The invention is based on the finding that increasing micro RNA-203 levels in induced pluripotent stem (iPSCs) or embryonic stem (ESCs) cells improves the quality cell fate potential and ability of these cells to differentiate into multiple cell lineages and to reach further maturation properties without interfering with their self-renewal properties. This effect is mediated through the mi R-203-dependent control of de novo DNA methyltransferases Dnmt3a and Dnmt3b, which in turn regulate the methylation landscape of pluripotent cells. The effect can be achieved by overexpression of micro RNA-203 or by adding micro RNA-203 or analogues thereof to the cell culture medium and can be observed using a variety of cellular and in vivo models. The generated cells are naïve pluripotent cells with an improved capacity to differentiate, that can be used to obtain more efficiently differentiated and mature cells proficient for regenerative medicine strategies.

The present invention provides an induced pluripotent stem (iPS) cell, or population of iPS cells, wherein the cell or cells giving rise to the iPS cell(s) are obtained from human postpartum tissue or cells, wherein the iPS cell(s) have increased levels of one or more factors selected from Group I: an Oct family member, a Sox family member, a Klf family member, a Myc family member, Nanog, Lin28, and combinations thereof. The present invention also provides differentiated cells derived from the cells of the invention and compositions, including pharmaceutical compositions comprising the cells of the invention. The invention further provides uses of the cells of the invention, e.g., in the treatment of a subject suffering from a disease of disorder. The invention additionally provides methods of generating iPS cell(s) from postpartum tissue, such as the cells of the invention.

The invention provides cell culture conditions for culturing stem cells, including feeder-free conditions for generating and culturing human induced pluripotent stem cells (iPSCs). More particularly, the invention provides a culture platform that allows long-term culture of pluripotent cells in a feeder-free environment; reprogramming of cells in a feeder-free environment; single-cell dissociation of pluripotent cells; cell sorting of pluripotent cells; maintenance of an undifferentiated status; improved efficiency of reprogramming; and generation of a nave pluripotent cell.

Provided herein are methods for the efficient in vitro differentiation of somatic cell-derived pluripotent stem cells to hematopoietic precursor cells, and the further differentiation of the hematopoietic precursor cells into immune cells of various myeloid or lymphoid lineages, particularly T cells, NK cells, and dendritic cells. The pluripotent cells may be maintained and differentiated under defined conditions; thus, the use of mouse feeder cells or serum is not required in certain embodiments for the differentiation of the hematopoietic precursor cells.

Provided herein are methods for the efficient in vitro maintenance, expansion, culture, and/or differentiation of pluripotent cells with disruption of the MeCP2 gene into various erythroid, myeloid, lymphoid, or endoderm lineages, particularly mature erythrocytes. The pluripotent cells may be maintained and differentiated under defined conditions; thus, the use of mouse feeder cells or serum is not required in certain embodiments for the differentiation of the precursor cells.

The disclosure relates to a method of reprogramming one or more somatic cells, e.g., partially differentiated or fully/terminally differentiated somatic cells, to a less differentiated state, e.g., a pluripotent or multipotent state. In further embodiments the invention also relates to reprogrammed somatic cells produced by methods of the invention, to chimeric animals comprising reprogrammed somatic cells of the invention, to uses of said cells, and to methods for identifying agents useful for reprogramming somatic cells.

According to the present invention, there are provided a method for producing a human T cell, which comprises the steps of inducing an iPS cell from a human T cell, and differentiating the iPS cell into a T cell; a pharmaceutical composition comprising the T cell produced by the method; and a method for cell-based immunotherapy using the method.