Sympathetic nervous system and PC12 pheochromocytoma-derived factors suppress stimulation of lymphocytes.

We have reported previously that ablation of the sympathetic nervous system augments immune responses in mice and rats. In the present study we show that a factor present in the sympathetic cervical ganglia of newborn rats suppresses Con A-induced stimulation of splenic T lymphocytes significantly whether added prior to, throughout, or following exposure to Con A. We also show that rat PC 12 pheochromocytoma cells secrete a factor which has the same inhibitory effect on T cell proliferation as the sympathetic ganglia-derived factor.