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VIP protects Th2 cells by downregulating granzyme B expression.

Vikas Sharma·Mario Delgado·Doina Ganea
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Abstract

Selective differentiation of Th1/Th2 effectors contributes to cell- or antibody-mediated immunity. Vasoactive intestinal peptide (VIP) induces Th2 responses by promoting Th2 differentiation and survival. Here we investigate the mechanisms of VIP-induced Th2 survival. Microarray and protein data indicate that VIP prevents the upregulation of granzyme B (GrB) in Th2, but not Th1 effectors. This is the first report of GrB expression and of its involvement in activation-induced apoptosis of T helper cells. The enhanced responsiveness of Th2 cells to VIP is probably due to the higher expression of VIP receptors and alternative signaling pathways. This study identifies GrB as a new significant player in Th1/Th2 activation-induced cell death, and characterizes the mechanisms for the protective effect of VIP on Th2 survival.

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ApoptosisDown-RegulationGene ExpressionGranzymesSerine EndopeptidasesTh2 CellsVasoactive Intestinal PeptideJournal ArticleResearch Support, N.I.H., ExtramuralResearch Support, Non-U.S. Gov't

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Vikas Sharma, Mario Delgado, Doina Ganea. 2006. VIP protects Th2 cells by downregulating granzyme B expression.. https://doi.org/10.1196/annals.1317.077

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