Described herein are methods and compositions related to generation of induced pluripotent stem cells (iPSCs). Improved techniques for establishing highly efficient, reproducible reprogramming using non-integrating episomal plasmid vectors. Using the described reprogramming protocol, one is able to consistently reprogram non-T cells with close to 100% success from non-T cell or non-B cell sources. Further advantages include use of a defined reprogramming media E7 and using defined clinically compatible substrate recombinant human L-521. Generation of iPSCs from these blood cell sources allows for recapitulation of the entire genomic repertoire, preservation of genomic fidelity and enhanced genomic stability.