The role of neuropeptides in the control of regional immunity.

Neuropeptides (NPs) and neurotransmitters are a heterogeneous group of soluble factors that make connections within the neuroendocrine and immune systems. NPs, including substance P (SP), vasoactive intestinal peptide (VIP), α melanocyte-stimulating hormone (α-MSH), and calcitonin gene-related peptide (CGRP), released by nerves that innervate the skin, can modulate the action of innate and adaptive skin immunity as well as the skin cells functions. Their role in several inflammatory skin diseases, such as atopic dermatitis, psoriasis, and vitiligo, and in the isotopic response has been reported. Further progress in understanding the various processes that modulate the interactions of the nervous and the skin immune system is essential to develop effective treatment for inflammatory skin conditions with neurogenic components and for understanding signs and symptoms in the isotopic response and, in general, in the control of global and regional immunity.