Detailed characterization of human Mycobacterium tuberculosis specific HLA-E restricted CD8+T cells

HLA-E presented antigens are interesting targets for vaccination given HLA-Es’ essentially monomorphic nature. We have shown previously that Mycobacterium tuberculosis (Mtb) peptides are presented by HLA-E to CD8+effector T cells, but the precise phenotype and functional capacity of these cells remains poorly characterized. We have developed and utilized in this study a new protocol combining HLA-E tetramer with intracellular staining for cytokines, transcription factors and cytotoxic molecules to characterize these cells in depth. We confirm in this study the significantly increased ex vivo frequency of Mtb-peptide/HLA-E-TM+CD8+T cells in the circulation of patients with active tubercu…