Effect of pregnancy zone protein on leucocyte migration inhibition, lymphoycte transformation and rosette formation by lymphocytes.

Pregnancy zone protein from pregnancy serum and control preparations from male serum were tested in lymphocyte transformation tests, in a system for rosette formation by T and B lymphocytes and in leucocyte migration inhibition tests using PPD-induced inhibition. PZ-protein preparations caused a dose dependent inhibition of lymphocyte transformation after stimulation with PHA, PPD and MLC. Inhibition was most pronounced in the PHA-system. In the rosette tests there was a tendency for T lymphocytes to bind fewer SRBC after incubation with PZ-protein while no effect on B rosettes was observed. In contrast, PPD-induced inhibition of leucocyte migration was abrogated effectively by PZ-protein, but not by corresponding fractions from male serum.