Corticotropin-releasing factor-induced immunosuppression in human and invertebrate immunocytes

1. Corticotropin-releasing factor (CRF) appears to be a potentially important signal molecule in both vertebrate and invertebrate neuroimmune and autoimmunoregulatory processes. It appears to mimic the effects of alpha-melanocyte stimulating hormone (MSH) but has a longer duration of action. 2. alpha-Helical CRF, a specific inhibitor of CRF, antagonizes CRF-induced cellular immunosuppression but is ineffective in altering MSH-induced immunosuppression. 3. Both human and Mytilus immunocytes appear to have specific CRF receptors. 4. In another experiment, both CRF and MSH antagonize tumor necrosis factor stimulation of immunocytes. Again, alpha-helical CRF antagonizes only CRF activity, further suggesting the presence of a separate CRF receptor on these cells.