HLA-E–dependent Presentation of Mtb-derived Antigen to Human CD8⁺ T Cells

Previous studies in mice and humans have suggested an important role for CD8⁺ T cells in host defense to Mtb. Recently, we have described human, Mtb-specific CD8⁺ cells that are neither HLA-A, B, or C nor group 1 CD1 restricted, and have found that these cells comprise the dominant CD8⁺ T cell response in latently infected individuals. In this report, three independent methods are used to demonstrate the ability of these cells to recognize Mtb-derived antigen in the context of the monomorphic HLA-E molecule. This is the first demonstration of the ability of HLA-E to present pathogen-derived antigen. Further definition of the HLA-E specific response may aid development of an effective vaccine against tuberculosis.