SYNTHETIC PEPTIDE WITH ANTIPROLIFERATIVE ACTIVITY - A SHORT C-TERMINAL FRAGMENT OF THE HUMAN INTERFERON ALPHA-2 MOLECULE

The biological activity of six synthetic peptides of the 124 - 144 region of the human interferon alpha-2 (IFN alpha-2) molecule was studied. Peptides were examined for their ability to inhibit mitogen induced proliferation of human blood cells in vitro. Only the peptide corresponding to the amino acid sequence 124 - 138 (2438) possessed IFN-like anti-proliferative activity. Other tested synthetic peptides did not affect cell proliferation in this experimental system. As with the native IFN alpha-2 molecule, the inhibitory effect of the peptide 2438 was dose-dependent. On simultaneous addition of peptide 2438, antiproliferative activity of IFN alpha-2 was enhanced. Direct cytotoxic effects of synthetic peptide 2438 were not revealed. These results suggest that a synthetic peptide corresponding to the 124 - 138-amino acid sequence of the human IFN alpha-2 molecule serves as a cytostatic agent.