Glycolipid Antigen - Mediated Invariant NKT Cell Activation in Microbial Immunity

Natural killer T (NKT) cells are T lymphocytes that express T cell antigen receptor (TCR) and NK receptors. NKT cells expressing invariant TCRs (iNKT cells) participate in the response to various microbial pathogens. In many cases, these cells respond to pathogens during the early phase of infection and affect the outcome of disease. iNKT cells respond to microorganisms by recognizing microbial glycolipid antigens, or by inflammatory cytokines produced by dendritic cells (DCs), with or without recognition of endogenous antigen. Recent studies show that iNKT cell antigen has a potent adjuvant activity that enhances the antigen-specific CD4 and CD8 T cell response and antibody production by B cells when a glycolipid antigen and a peptide or a DNA vaccine were co-administered. Therefore, glycolipid antigen- mediated iNKT cell activation could be applied to the design of a new type of combined vaccination.