CCR6 and tuberculosis: Majority of the MAIT cells in healthy subjects expressed a significantly higher level of CCR6 (median, 89.7%; range, 68.1–98.7) as compared to HIV/TB co-infections without treatment (median, 46.6%; range, 1.3–68.8; P<0.0001), HIV without treatment (median, 73.8%; range, 37.6–97.1; P<0.05), HIV with treatment (median, 59.7%; range, 23.4–95.6; P<0.001) (Fig 3C).