Specifically, HLA-E-restricted CTLs recognizing pathogen-derived peptides have been documented in bacterial (Mycobacterium tuberculosis and Salmonella enterica)9–11,48,49 and viral infections (HCMV, EBV14,15,17) revealing the likely role of these cells in host defense, complementary to that of conventional HLA-Ia-restricted CTLs8,50–52. The gene discussed is HLA-E; the disease is viral infectious disease.