Functional and molecular characterization of VIP receptors and signal transduction in human and rodent immune systems

In the last few decades, as a result of the interaction between different areas of research, the new interdisciplinary and exciting field of neuroimmunology has emerged. In this context, it has been demonstrated that small peptides may function in a communication network that links nervous, endocrine, and immune systems. Thus, each peptide may function as a neurotransmitter, peptide hormone, or cytokine, depending on its site of release and the target cell with which it interacts. Among these peptides, vasoactive intestinal peptide (VIP) has been shown to play a very important role in the regulation of immune function. The first stage in the action of VIP with immunocompetent cells is the binding to specific plasma membrane receptors and the generation of an intracellular signal. In this review, we focus and present data about the signal transduction pathway of VIP in both human and rodent immunocompetent cells.