FUNDAMENTAL-ASPECTS OF NEURAL-IMMUNE SIGNALING

Noradrenergic and peptidergic nerve fibers abundantly innervate the pa renchyma of both primary (bone marrow) and secondary (spleen, lymph no des) lymphoid organs. Nerve fibers distribute within the parenchyma of these organs, as well as along smooth muscle compartments. Both norad renaline and peptides such as substance P have been shown to fulfill t he basic criteria for neurotransmission with lymphocytes, macrophages, and other immunocytes as targets. Denervation or pharmacological mani pulation of these neurotransmitters can profoundly alter immunological reactivity at the individual cellular level, at the level of complex multicellular interactions (such as antibody response), and at the lev el of host response to a disease-producing challenge. The characterist ic and mechanisms of bidirectional neural-immune signaling may provide a novel approach to immunologically-mediated disease, both pharmacolo gically and behaviorally.