UPREGULATION OF GAMMA/DELTA T CELL ACTIVATION BY NEUTROPHIL SERINE-PROTEASES

TOWSTYKA N; SABBIONE F; GORI S; SALAMONE G; TREVANI A; GEFFNER J; JANCIC C

Congreso; Reunión Anual Conjunta LXIII SAI - IV LASID ? II FAIC; 2015

SAI-LASID-FAIC

Background: Gamma/delta T cells play a critical role in the recruitment and activation of neutrophils at the sites of infection, in addition, neutrophils can regulate gamma/delta T cell activity. We have previously reported that neutrophils regulate gamma/delta T cell activation induced by anti-CD3 antibodies and this process was independent on caspase-1 activation. Now, we aim to investigate the role of leukocyte serine-proteases during this process, since it is known that these proteases can induce the activation of conventional T cells. Methods: gamma/delta T cells were purified from human peripheral blood mononuclear cells, by using an anti-TCR gamma/delta MicroBead isolation kit. Neutrophils were isolated by dextran sedimentation. After purification, gamma/delta T cells were stimulated with anti-CD3 antibodies (250 ng/ml, 60 min), and then were cultured with or without neutrophils. After 24 hours, we analyzed the CD69 expression and IFN-gamma production by gamma/delta T cells by flow cytometry and ELISA, respectively. We evaluated the secretion of elastase by neutrophils using a specific substrate and spectrophotometry analysis. Results: Treatment of neutrophils with the serine-proteases inhibitor, AEBSF, completely abrogated the up-regulation of CD69 expression (p