Reciprocal stimulation of gammadelta T cells and dendritic cells during the anti-mycobacterial immune response.
Gammadelta T cells and dendritic cells (DC) are two distinct cell types of innate immunity that participate in early phases of immune response against Mycobacterium tuberculosis infection. Here we show that a close functional relationship exists between these cell populations. Using an in vitro coculture system, Vgamma1 T cells from Tcrb(-/- )mice were found to be activated by DC infected in vitro with BCG, as indicated by the elevated CD69 expression, IFN-gamma secretion and cytotoxic activity. This activation process was due to a non-cognate mechanism since it required neither cell to cell contact nor interaction between the TCR and a specific antigen, but was mediated by DC-derived IL-12. Reciprocally, Vgamma1 T cells provided a key cytokine, IFN-gamma, which increased IL-12 production by BCG-infected DC. Moreover, exposure of BCG-infected DC to Vgamma1 T cells conditioned the former to prime a significantly stronger anti-mycobacterial CD8 T cell response. Consequently, stimulation of gammadelta T cells and their non-cognate interaction with DC could be applied as an immune adjuvant strategy to optimize vaccine-induced CD8 T cell immunity.
Dieli
Francesco
F
Dipartimento di Biopatologia, Università di Palermo, Palermo, Italy. dieli@unipa.it
Caccamo
Nadia
N
Meraviglia
Serena
S
Ivanyi
Juraj
J
Sireci
Guido
G
Bonanno
Cesira T
CT
Ferlazzo
Viviana
V
La Mendola
Carmela
C
Salerno
Alfredo
A
D000818:Animals; D018414:CD8-Positive T-Lymphocytes / Q000276:immunology* / Q000382:microbiology; D002454:Cell Differentiation / Q000276:immunology; D018920:Coculture Techniques; D003601:Cytotoxicity Tests, Immunologic; D003713:Dendritic Cells / Q000166:cytology / Q000276:immunology* / Q000382:microbiology; D004797:Enzyme-Linked Immunosorbent Assay; D005260:Female; D007371:Interferon-gamma / Q000276:immunology; D018664:Interleukin-12 / Q000276:immunology; D008213:Lymphocyte Activation / Q000276:immunology; D008297:Male; D051379:Mice; D008810:Mice, Inbred C57BL; D018345:Mice, Knockout; D009169:Mycobacterium tuberculosis / Q000276:immunology*; D016692:Receptors, Antigen, T-Cell, gamma-delta / Q000276:immunology*; D013047:Specific Pathogen-Free Organisms; D016176:T-Lymphocyte Subsets / Q000276:immunology* / Q000382:microbiology; D014376:Tuberculosis / Q000276:immunology* / Q000382:microbiology / Q000517:prevention & control
D016692:Receptors, Antigen, T-Cell, gamma-delta; D018664:Interleukin-12; D007371:Interferon-gamma