Patent ID: 8900871

Claim:
A method of producing iPS cells in vitro, comprising introducing (a) an episomal vector comprising a nucleic acid sequence that encodes Oct3/4, (b) an episomal vector comprising a nucleic acid sequence that encodes Klf4, (c) an episomal vector comprising a nucleic acid sequence that encodes Sox2, (d) an episomal vector comprising a nucleic acid sequence that encodes (i) L-Myc, and (ii) Lin28 or Lin28b joined polycistronically in the orientation of 5′-3′, and (e) a functional inhibitor of p53 selected from the group consisting of (i) an siRNA against p53, (ii) an shRNA against p53, and (iii) DNA encoding an siRNA or shRNA against p53, wherein the DNA can be in the form of an episomal vector, into a somatic cell such that iPS cells are produced, wherein the episomal vectors of (a) to (e) can be the same or different.