From rxpgnews.com
Genetic selection of mouse male germline stem cells in vitro: Offspring from single stem cells
By Pankaj, US Correspondent,
Jan 4, 2005 - 6:55:38 PM
Since the classic work of Brinster and colleagues demonstrating that spermatogonial stem cells could be transplanted within seminiferous tubules, where they proliferate and undergo sperm development, it has been hoped that the system could be adapted for germline modifications. This, however, entails a number of challenging technical steps such as the propagation of cultures of spermatogonial stem cells, introduction of genetic modifications, and selection of the modified stem cells.
Mito Kanatsu-Shinohara and colleagues met the first challenge with a cocktail of growth factors, published previously in Biology of Reproduction (Kanatsu-Shinohara M, Ogonuki N, Inoue K, Miki H, Ogura A, Toyokuni S, Shinohara T. Long-term proliferation in culture and germline transmission of mouse male germline stem cells. Biol Reprod 2003; 69: 612-616.); they refer to the spermatogonial stem cells established in this way as germline stem cells (GS). In the January 2005 issue of Biology of Reproduction, this group reports another very significant step forward. They transfected the GS cells with a construct designed to express both enhanced green fluorescent protein (EGFP) and neo to allow drug selection of modified cells. The colonies derived from single modified and selected GS cells were expanded and then injected into seminiferous tubules of germ cell-free mutant mice. After mating, these mice produced offspring that not only expressed the introduced EGFP construct but also passed it on to their offspring and subsequent generations. This groundbreaking work sets the stage for further germline modifications that will be important for a wide range of experimental analyses. Further, this work will have profound implications if the technologies can be applied to the clinic.
All rights reserved by RxPG Medical Solutions Private Limited ( www.rxpgnews.com )