The present disclosure relates generally to novel methods and compositions for using engineered reprogramming factor(s) for the creation of induced pluripotent stem cells (iPSCs) through a kinetically controlled process. Specifically, this disclosure relates to establishing combinations of reprogramming factors, including fusions between conventional reprogramming factors with transactivation domains, optimized for reprogramming various types of cells. More specifically, the exemplary methods disclosed herein can be used for creating induced pluripotent stem cells from various mammalian cell types, including human fibroblasts. Exemplary methods of feeder-free derivation of human induced pluripotent stem cells using synthetic messenger RNA are also disclosed.

The invention relates to a method for reprogramming cells from aged donors or senescent cells to pluripotent cells that have lost marks of senescence. In particular, the invention relates to an ex vivo method for preparing induced pluripotent stein cells (iPSCs) from a target cell population comprising cells from aged donors or senescent cells, said method comprising the steps of culturing said target cell population tinder appropriate conditions for reprogramming said cells into iPSCs, wherein said appropriate conditions comprises increasing expression in said target cells, of at least the following reprogramming factors: Oct4, Klf4, Sox2, Myc, Lin28 and, optionally Nanog.

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.

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.

Disclosed are findings that: (a) induced pluripotent stem cells derived from aged donors (A-iPSC) show increased genomic instability, a defect in apoptosis, a defect in glucose metabolism, and a blunted DNA damage response are compared to those derived from young donors (Y-iPSC); and (b) inhibition of excessive glutathione-mediated H.sub.2O.sub.2 scavenging activity, found to be associated with A-iPSC and in turn inhibiting DNA damage response and apoptosis, substantially rescues these defects and reduces the oncogenic potential of A-iPSC. Supplementation of pluripotency factor ZSCAN10 (shown to be poorly activated in A-iPSC and to act upstream of glutathione involvement), e.g., by expression as an adjunct to the four Yamanaka iPSC reprogramming factors, led to substantial recovery of genomic stability, DNA damage response, and apoptosis in A-iPSC through enhancing GLUT3 and normalizing homeostasis of glutathione/H.sub.2O.sub.2; GLUT3 (a pluripotent stem cell-specific glucose transporter acting upstream of glutathione and also poorly activated in A-iPSC) has similar effects, indicating that inhibition of glutathione/H.sub.2O.sub.2 notably through delivery of ZSCAN 10 and/or GLUT3 and/or an exosome subunit will be clinically useful, resulting in A-iPSC of improved properties and reduced oncogenic potential.

The present disclosure provides methods of producing iPSCs comprising contacting a cell (e.g., CD34+ cell or other blood cell) in suspension with one or more circular RNAs encoding one or more reprogramming factors and maintaining the cell under conditions under which a reprogrammed iPSC is obtained. In some embodiments, the circular RNA encodes a reprogramming factor (selected from Oct3/4, Klf4, Sox2, Nanog, Lin28, c-Myc, or L-Myc, or a fragment or variant thereof.

The present invention provides compositions and methods for reprogramming somatic cells using purified RNA preparations comprising single-strand mRNA encoding an iPS cell induction factor. The purified RNA preparations are preferably substantially free of RNA contaminant molecules that: i) would activate an immune response in the somatic cells, ii) would decrease expression of the single-stranded mRNA in the somatic cells, and/or iii) active RNA sensors in the somatic cells. In certain embodiments, the purified RNA preparations are substantially free of partial mRNAs, double-stranded RNAs, un-capped RNA molecules, and/or single-stranded run-on mRNAs.

The present invention relates in pan to methods for producing tissue-specific cells from patient samples, and to tissue-specific cells produced using these methods. Methods for reprogramming cells using RNA are disclosed. Therapeutics comprising cells produced using these methods are also disclosed.

This document provides methods and materials related to induced pluripotent stem cells. For example, induced pluripotent stem cells, compositions containing induced pluripotent stem cells, methods for obtaining induced pluripotent stem cells, and methods for using induced pluripotent stem cells are provided. In addition, methods and materials for using induced pluripotent stem cells to repair tissue (e.g., cardiovascular tissue) in vivo as well as methods and materials for using induced pluripotent stem cells to assess their therapeutic potential in appropriate animal models are provided.

A culture medium is provided which is capable of establishing expanded potential stem cell (EPSC) lines which resemble naive or ground state ES cells, but are also able to differentiate into placenta trophoblasts and the embryo proper. Methods are provided using the medium for the in vitro conversion and maintenance of cells, including pluripotent cells into EPSCs.