Figure 4
MAITs respond to bacterial pathogens in vivo. Four macaques were challenged with BCG intradermally and monitored for 6 weeks. (a) Frequency of MAITs in the blood of BCG vaccinated macaques. Mean and s.e.m. are shown. Kruskal Wallis test revealed no significant differences in MAIT frequencies. (b) Frequency of Ki-67+ MAITs (blue) and non-MAIT CD8+ T cells (red) in the blood. Mean, s.e.m, and P-values (Friedman test with Dunn’s multiple comparison post-test) are shown (*P⩽0.05, **P⩽0.01). Animals were revaccinated with BCG 9-weeks post-initial vaccination. These animals were brought to necropsy at days 13 and 14 for analysis. (c) Representative MR1-tetramer, Ki-67, and GzmB staining from the pectoral (top, vaccine site) and inguinal (bottom, non-vaccine site) skin sections. (d) Frequency of MAITs of CD8+ T cells in the chest and thigh skin sections (left) and in the axillary and inguinal lymph nodes (right). (e) Percentage of Ki-67+ MAITs in the chest and thigh skin (left) and axillary and inguinal lymph nodes (right). (f) Frequency of GzmB+ MAITs in the skin (left) and lymph nodes (right). (g) Comparison of Ki-67+ frequencies among MAITs and non-MAIT CD8+ T cells in the chest (left), thigh (middle), and axillary lymph node (right). Mean, s.e.m., and P-values (Wilcoxon rank-sum test) are shown for(d–g). (h) Ki-67+ frequency of MAITs (blue) and not MAITs (red) after re-vaccination. (i) MAIT frequencies of CD8+ T cells in blood after TB infection. (j) MAIT and non-MAIT CD8+ T cell Ki-67 frequencies after Mtb infection. Mean, s.e.m., and P-values (Friedman test with Dunn’s multiple comparison post-test) are shown (*P⩽0.05; **P⩽0.01; ***P⩽0.001). BCG, Bacillus Calmette-Guerin; MAITs, mucosal-associated invariant T cells; MR1, major histocompatibility complex related protein 1; Mtb, Mycobacterium tuberculosis.
