Professional antigen-presentation function by human gammadelta T Cells.

Human [gamma][delta] T cells are considered to play a vital role in protective immunity through cytokine secretion and cytotoxic activity. We report that cells expressing the V[gamma]2V[delta]2⁺-T cell receptor (V[delta]2⁺ T cells) also display principal characteristics of professional antigen-presenting cells such as dendritic cells. Thus, when activated, these cells efficiently processed and displayed antigens and provided co-stimulatory signals sufficient for strong induction of naive [alpha]{szligbeta} T cell proliferation and differentiation. We suggest that, upon microbial activation, V[delta]2⁺ T cells participate in the induction of adaptive immune responses and that these cells may be a useful tool in vaccine development and immunotherapy.