Proline-rich polypeptide from ovine colostrum: its effect on skin permeability and on the immune response.

The effect of a proline-rich polypeptide from ovine colostrum on the humoral immune response in mice against sheep red blood cells (SRBC) was studied. It was shown that the polypeptide had a regulatory activity stimulating or suppressing the immune response. The proline-rich polypeptide also increased the permeability of skin vessels in guinea-pigs. Studies on the mechanism of the effect of the proline-rich polypeptide suggest that prostaglandins are involved in the activity of the polypeptide.