IL17A and tuberculosis: As shown in Figure 3A, TB antigens and anti-CD3 induced the expression of any or all three cytokines in CD4+ T cells; however, examination of Th22 cells failed to reveal any significant alteration in the frequency of this population (IL-22+IL-17A–IFN-γ–) in TBL patients compared with PTB individuals at baseline or following antigen or anti-CD3 stimulation (Figure 3, B–E).