CD8⁺ T-cell responses in controllers and noncontrollers with and without protective class I HLA alleles. (A) Patient immunogenetics. The bar graphs show the percentage of patients in this study with HLA-B57 (far left); any protective class I HLA (HLA-B13, B27, B57, B58, B81; second from left); HLA-DRB1*13 and/or DQB1*6 (third from left); and both protective class I and class II alleles (far right). (B) Total magnitude of the CD8⁺ T-cell response in rectal mucosa. Horizontal bars represent the median for each group. *P < .05, **P < .01, ***P < .001. (C) Overall polyfunctionality of the CD8⁺ T-cell response in rectal mucosa. Each pie slice represents a different functional category: black indicates 5 functions; purple, 4 functions; dark blue, 3 functions; light blue, 2 functions; green, 1 function. The number in the center of each pie represents the median percentage of responding cells responding in any way to Gag stimulation. Statistical differences between groups are written above pie charts. (D) Mucosal CD8⁺ T-cell polyfunctional responses broken down into 31 individual response categories. Each bar represents the median and interquartile ranges for the frequency of responding cells for a different patient group and class I HLA status as indicated by the colored rectangle beneath each pie (ie, blue indicates controllers/protective HLA). The colored bars below the x-axis relate to the pie slice colors in panel B. Statistical differences between controllers with protective class I alleles and other patient groups are marked by an asterisk (*) and color coded for each patient group (red indicates controller/nonprotective HLA; green, noncontroller/protective HLA; purple, noncontroller/nonprotective HLA). All differences are significant at P < .01.