Introduction
Stem cells generally are defined as immature cells found in the body that can renew themselves throughout the life of an individual as well as differentiate into a broad range of tissues within the body. Moraga's scientists have discovered a very primitive (primordial) stem cell in adult tissues. These newly discovered adult stem cells are similar in function to the cells of the morula (loosely defined as a cluster of at least 8-16 embryonic cells during embryogenesis). Any one of these cells forming the morula has the potential to give rise to all tissues of the body including gametes (i.e. oogonia and spermatogonia). These cells are called blastomeres.
The Company's scientists have found that these primitive blastomere-like
stem cells (BLSCs) appear to be retained in adult tissues; since these newly
isolated cells can be induced in culture to express cell surface markers
found only on spermatogonia. The BLSCs also express surface markers previously
found only on embryonic cells. Hence, the Company's BLSCs appear to be
totipotent in their potential to not only differentiate into most tissue
and organs of the body, but under appropriate culture conditions, they also
may become gametes.