The influence of the non-dialysable sugar-peptide fraction from bovine blood plasma on the amino acid incorporation of BHK-21 normal and RSV transformed cells.

The non-dialysable sugar-peptide rich fraction of bovine blood plasma has been studied with regard to its influence on the amino acid incorporation of BHK-21 and BHK/RSV cells in vitro. The results indicate that the Nsp fraction contains a peptide factor(s) causing changes in activity for the protein and DNA synthethizing system in both the cell cultures examined. The biological activity of the factor(s) is regulated by interaction with blood serum components and this fact may play a leading role in its regulatory function.