WASHINGTON (Xinhua) – Israeli and British researchers said Wednesday they have successfully used human cells to create primordial germ cells that develop into egg and sperm for the first time.
The study, published in the US journal Cell, could help yield insight into fertility problems and early stages of embryonic development and potentially, in the future, enable the development of new kinds of reproductive technology.
“Researchers have been attempting to create human primordial germ cells (PGCs) in the petri dish for years,” said Jacob Hanna of Weizmann Institute of Science in Israel, who led the study.
“PGCs arise within the early weeks of embryonic growth, as the embryonic stem cells in the fertilised egg begin to differentiate into the very basic cell types. Once these primordial cells become ‘specified’, they continue developing toward precursor sperm cells or ova “pretty much on autopilot”, said Hanna.
The idea of creating these cells took off with the 2006 invention of induced pluripotent stem (iPS) cells – adult cells that are “reprogrammed” to look and act like embryonic stem cells, which can then differentiate into any cell type.
Several years ago, researchers in Japan successfully got mouse iPS cells to differentiate into PGCs, but efforts to replicate the achievement in human cells have failed.
The researchers found that the mouse embryonic cells are easily kept in their stem cell state in the lab, while human iPS cells have a strong drive to differentiate.
In the new study, Hanna’s team created a method to tune down the genetic pathway for this differentiation, thus creating a new type of iPS cell that they dubbed “naive cells”.