Helminth infections are associated with decreased frequencies of mono- and multifunctional mycobacterial antigen-specific CD4⁺ Th1 cells in active TB.

<p>Whole blood was cultured with media alone, CFP-10, ESAT-6 or anti-CD3 for 6 h and the baseline or net frequencies of mono - and multifunctional Th1 cells determined. (A) Representative whole blood intracellular cytokine assay flow data from an active TB individual showing expression of Th1-associtated cytokines. The plots shown are gated on CD3⁺CD4⁺ T cells. (B-E) The spontaneous frequencies (B) are shown as scatter plots the net frequencies of mono– and multifunctional CD4⁺ Th1 cells following CFP-10 (C) or ESAT-6 (D) or anti-CD3 (E) stimulation are shown as bar graphs. All individuals had pulmonary TB with concomitant filarial infection (FIL/TB, n = 17) or concomitant Strongyloides infection (STR/TB, n = 13) or no helminth infection (TB, n = 20). The bars represent the geometric mean and 95% confidence intervals. Net frequencies were calculated by subtracting baseline frequency from the antigen–induced or anti-CD3 induced frequency for each individual. P values were calculated using the Kruskal-Wallis test with Dunn's multiple comparisons (* p<0.05, ** p<0.01, *** p<0.001).