In TB vaccine-immunized non-human primates (NHPs), T cell subsets associated with protection include multifunctional antigen-specific Th1/Th17 CD4 and CD8 T cells (10, 11), and Mtb-specific CD4 and CD8 T cells with circulating central memory or tissue-resident memory phenotypes (12). The gene discussed is CD8A; the disease is tuberculosis.