Researchers at the University of Pennsylvania have demonstrated a surprising capability: monkey blood cells can be coaxed to regain the flexible properties of stem cells, enabling them to become precursors to sperm cells. The findings were reported in a scientific publication; further details appear in a contemporary journal issue.
Different cell types carry distinct abilities tailored to their roles in the body. Yet most cells cannot dramatically alter their function. Stem cells are the exception, possessing the potential to become many different cell kinds when needed.
In this work, induced pluripotent stem cells derived from various cellular sources, including blood and cells with embryonic-like characteristics, were directed to produce germ-line precursors such as spermatogonial stem cells. These cells form the foundation for downstream germ-cell development and the eventual creation of sperm cells.
Before the first meiotic division, spermatocytes hold two complete sets of chromosomes. They then progress to a stage with paired chromosomes again, followed by a division that yields haploid cells called spermatids. Spermatids mature into spermatozoa, the mature male germ cells responsible for fertilization.
The researchers emphasize that these advances could pave the way for laboratory production of germ cells—sperm and eggs—and offer new strategies for addressing infertility. Such work holds promise for new reproductive therapies and a better understanding of how germ cells arise and develop in humans and related species [Study authors, year].