Control of Human Fibroblast Proliferation.

摘要

We have found that diploid human fibroblasts, but not heteroploid human fibroblasts, stringently required serum for their multiplication. Using Diaflo ultrafiltration membrane units, isoelectric focusing, and preparative gel electrophoresis, we have isolated and purified this mitogenic activity from mammalian sera. This electrophoretically homogeneous sialoprotein is 120,000 daltons in size, with an isoelectric point of pH 5.2-5.4; it is made up of two electrophoretically identical dimers weighing 57,000 each; it is thermostable and is inactivated by both trypsin and neuraminidase. (jes)