Neuroimmune interactions in allergic skin diseases

Abstract

Recent studies have advanced our understanding that allergic inflammation triggers neuronal dysfunction, thereby modulating inflammation-related changes in affected tissues including the skin. Vice versa, evidence has emerged that inflammatory responses are controlled by neurons. Moreover, structural cells and invading immune cells express neuronal receptors and release mediators which directly communicate with nerve endings in the skin. During the allergic response, skin cells do not only represent a significant source of neuromediators but also represent targets for neuropeptides or neurotrophins as well as neurotransmitters in the inflamed tissue. During the last decade, it has become obvious that a large variety of molecules influence the adaptive as well as the innate immune response. Beside neuropeptide receptors, proteinase-activated receptors, novel histamine receptors, different cytokine or chemokine receptors play a role in the pathophysiology of atopic and allergic diseases. Peripheral sensory and autonomic nerves are critically involved in many pathways of the innate and adoptive immune system during allergic and atopic skin diseases. Further dissection of receptor-mediated and intracellular signal pathways will help to develop more effective therapeutic approaches for allergic and inflammatory skin diseases.