Predominance of gonadotropin alpha-subunit resulting from preferential loss of hCG beta production in an established cell line.

The BeWo line of trophoblastic cells, maintained in continuous culture since 1966, was employed to investigate the phenomenon of gonadotropin alpha-subunit predominance that exists in several cell lines. The secretion of complete human chorionic gonadotropin (hCG) relative to alpha-subunit was compared in several different BeWo sublines, all of where were derived from BeWo stock roller tube colonies. In all of the BeWo sublines, secretion of hCG originally exceeded secretion of alpha-subunit. With time in culture, however, there was a marked decline in production of hCG/hCG beta, but not in alpha-subunit. Thus it appears that the production of hCG beta by BeWo choriocarcinoma cells is more labile than the production of the alpha-subunit.