title: Multifunctional immune responses of HMBPP-specific Vγ2Vδ2 T cells in M. tuberculosis and other infections.
abstract: Vγ2Vδ2 T (also known as Vγ9Vδ2 T) cells exist only in primates, and in humans represent a major γδ T-cell sub-population in the total population of circulating γδ T cells. Results from recent studies suggest that while (E)-4-hydroxy-3-methyl-but-2-enyl pyrophosphate (HMBPP) phosphoantigen from Mycobacterium tuberculosis (Mtb) and other microbes activates and expands primate Vγ2Vδ2 T cells, the Vγ2Vδ2 T-cell receptor (TCR) recognizes and binds to HMBPP on antigen-presenting cells (APC). In response to HMBPP stimulus, Vγ2Vδ2 TCRs array to form signaling-related nanoclusters or nanodomains during the activation of Vγ2Vδ2 T cells. Primary infections with HMBPP-producing pathogens drive the evolution of multieffector functional responses in Vγ2Vδ2 T cells, although Vγ2Vδ2 T cells display different patterns of responses during the acute and chronic phases of Mtb infection and in other infections. Expanded Vγ2Vδ2 T cells in primary Mtb infection can exhibit a broader TCR repertoire and a greater clonal response than previously assumed, with different distribution patterns of Vγ2Vδ2 T-cell clones in lymphoid and non-lymphoid compartments. Emerging in vivo data suggest that HMBPP activation of Vγ2Vδ2 T cells appears to impact other immune cells during infection.
authors.affiliation: Department of Microbiology and Immunology, Center for Primate Biomedical Research, University of Illinois College of Medicine Chicago, Chicago, IL 60612, USA. zchen@uic.edu
authors.forename: Zheng W
authors.initials: ZW
authors.lastname: Chen
mesh_terms: D000818:Animals; D000942:Antigens, Bacterial / Q000276:immunology*; D006801:Humans; D008213:Lymphocyte Activation; D009169:Mycobacterium tuberculosis / Q000276:immunology*; D010755:Organophosphates / Q000276:immunology*; D016692:Receptors, Antigen, T-Cell, gamma-delta / Q000276:immunology*; D013601:T-Lymphocytes / Q000276:immunology*; D014376:Tuberculosis / Q000276:immunology*
chemical_list: C467061:4-hydroxy-3-methyl-2-butenyl diphosphate; D000942:Antigens, Bacterial; D010755:Organophosphates; D016692:Receptors, Antigen, T-Cell, gamma-delta