I am working with reprogramming to obtain induced pluripotent stem cells derived from urinary progenitor cells. I succeed with a sample from a young volunteer (child), but with a sample of her mother, the cells were not doing well, not growing as expected, looking senescent, and are not showing colonies in the expected time. For the first reprogramming, I adapted the cells after electroporation directly to the pluripotent stem cell medium, StemFlex, but now I am using ReproTeSR, expecting to change the medium to StemFlex after the appearance of the colonies. It is the second time that I do the reprogramming of the mother, and it is not going well. Could be de medium? Could be the age of the cells?