Gamma interferon secretion by human Vgamma2Vdelta2 T cells after stimulation with antibody against the T-cell receptor plus the Toll-Like receptor 2 agonist Pam3Cys.
Circulating Vgamma2Vdelta2 T-cell populations in healthy human beings are poised for rapid responses to bacterial or viral pathogens. We asked whether Vgamma2Vdelta2 T cells use the Toll-like receptor (TLR) family to recognize pathogen-associated molecular pattern molecules and to regulate cell functions. Analysis of expanded Vgamma2Vdelta2 T-cell lines showed the abundant presence of TLR2 mRNA, implying that these receptors are important for cell differentiation or function. However, multiple efforts to detect TLR2 protein on the cell surface or in cytoplasmic compartments gave inconsistent results. Functional assays confirmed that human Vgamma2Vdelta2 T cells could respond to the TLR2 agonist (S)-(2,3-bis(palmitoyloxy)-(2RS)-propyl)-N-palmitoyl-(R)-Cys-(S)-Ser(S)-Lys4-OH trihydrochloride (Pam3Cys), but the response required coincident stimulation through the gammadelta T-cell receptor (TCR). Dually stimulated cells produced higher levels of cytoplasmic or cell-free gamma interferon and showed increased expression of the lysosome-associated membrane protein CD107a on the cell surface. A functional TLR2 that requires coincident TCR stimulation may increase the initial potency of Vgamma2Vdelta2 T-cell responses at the site of infection and promote the rapid development of subsequent acquired antipathogen immunity.
Deetz
Carl O
CO
Institute of Human Virology, University of Maryland Biotechnology Institute, 725 West Lombard Street, Baltimore, Maryland 21201, USA.
Hebbeler
Andrew M
AM
Propp
Nadia A
NA
Cairo
Cristiana
C
Tikhonov
Illia
I
Pauza
C David
CD
D000906:Antibodies / Q000276:immunology*; D002460:Cell Line; D002478:Cells, Cultured; D004151:Dipeptides / Q000276:immunology* / Q000494:pharmacology; D005434:Flow Cytometry; D006801:Humans; D007371:Interferon-gamma / Q000378:metabolism*; D008074:Lipoproteins / Q000276:immunology* / Q000494:pharmacology; D008213:Lymphocyte Activation; D016692:Receptors, Antigen, T-Cell, gamma-delta / Q000276:immunology* / Q000378:metabolism; D015398:Signal Transduction; D013601:T-Lymphocytes / Q000187:drug effects / Q000276:immunology* / Q000378:metabolism; D051195:Toll-Like Receptor 2 / Q000819:agonists* / Q000235:genetics / Q000378:metabolism
D000906:Antibodies; D004151:Dipeptides; D008074:Lipoproteins; D016692:Receptors, Antigen, T-Cell, gamma-delta; D051195:Toll-Like Receptor 2; D007371:Interferon-gamma; C047210:2,3-bis-(palmitoyloxy)-2-propyl-N-palmitoyl-cysteinylserine