Open AccessThe neuropeptide substance P stimulates the effector functions of platelets
Author(s) -
DAMONNEVILLE M.,
MONTÉ D.,
AURIAULT C.,
CAPRON A.
Publication year - 1990
Publication title -
clinical & experimental immunology
Language(s) - English
Resource type - Journals
SCImago Journal Rank - 1.329
H-Index - 135
eISSN - 1365-2249
pISSN - 0009-9104
DOI - 10.1111/j.1365-2249.1990.tb03343.x
Subject(s) - platelet , biology , immunoglobulin e , neuropeptide , population , cytotoxic t cell , immunology , effector , immune system , antibody , biochemistry , receptor , in vitro , medicine , environmental health
SUMMARY Sensory neuropeptides, such as substance P. appear as potent mediators of various immunological reactions, and inhibit or stimulate a wide range of functions of immune inflammatory cells. Platelets were recently shown to participate as effector cells in an IgE or lymphokine‐dependent killing of parasites. Substance P and its carboxy‐terminal fragment SP (4–11) induce the cytotoxic activity of platelets towards the larvae of Schistosoma mansoni , respectively, by 90% and 40%, whereas the modified C terminal SP, the SP‐free acid, exhibits no effect on the platelets. The neuropeptide effects occur at low doses (10‐ 8 M), are specific as shown by inhibition studies with a substance P antagonist, theD‐SP. Binding data obtained after flow cytofluorometry with FITC‐SP lead to the conclusion that SP binds specifically to about 20% of the homogenous population of platelets. Moreover, IgE could modulate the SP‐dependent functions of platelets since the pre‐incubation with myeloma human IgE or with AP2 monoclonal antibodies—known to inhibit the IgE‐dependent killing of these cells leads to a dramatic decrease of the SP dependent cytotoxic activity of platelets towards the larvae. These findings identify a potent mechanism for nervous system regulation of host defence responses.