NEUROPEPTIDE SIGNALING OF LYMPHOCYTES IN IMMUNOLOGICAL RESPONSES

Peptidergic nerves in immune organs and lymphoid tissues of the lungs and gastrointestinal tract end on or in close proximity to lymphocytes , mast cells and macrophages. Vasoactive intestinal peptide, substance P and some other neuropeptides, that are recognized by distinct sets of cell surface receptors, regulate aspects of T cell differentiation in the thymus, such as negative selection, and contribute to mediating compartmental immune responses. The latter effects include stimulatin g expression of adhesive proteins by lymphocytes, enhancement of lymph ocyte and macrophage migration in vascular and connective tissues, and modulation of proliferative and synthetic responses of lymphocytes to diverse antigens.