SENS4, Session 4: Adult regenerative capacity

Brandon Reines presented a counterintuitive result on regeneration: sometimes old animals have a higher regenerative capacity than young animals. In particular, if you punch a hole in the ear of a young mouse, then it won’t heal; but in a middle-aged mouse it will heal completely. He argued that this happens because mouse ear connective tissues never fully differentiate, and suggested that other neural-crest-derived connective tissues might show similar properties.

Kaisa Selesniemi talked about possible methods for sustaining fertility in older women. They found that an infusion of bone marrow from younger females keeps older mice fertile longer; they are also conducting a high-throughput screen of chemical libraries to find compounds that might stimulate stem cells to produce new oocytes. They hope that these treatments might not only prolong fertility, but also female health: mice with longer “ovarian lifespan” show reduced disease incidence.

Alexandra Stolzing presented a new method for generating induced pluripotent stem cells (i.e., for reprogramming adult somatic cells to become pluripotent) that doesn’t use viral compounds or plasmids. Viruses can cause abnormalities in the reprogrammed cells, so much recent work has focused on developing alternate methods for deriving iPS cells.

(For an index of coverage of all sessions, see here.)