Attenuation of Helper T Cell Capacity for TH1 and TH17 Differentiation in Children With Nontuberculous Mycobacterial Infection.

Nontuberculous mycobacteria (NTM) infect children with increasing frequency worldwide. Using blood and lymph node tissue from children with NTM lymphadenitis, and uninfected lymph node tissue from community controls, we evaluated helper T (TH) cells in functional assays of TH1/TH17 differentiation and measured the concentration of their associated cytokines at the site of infection. Circulating TH cells from infected children were attenuated in their TH1/TH17 differentiation capacity and expressed less interferon γ and interleukin 17 after polyclonal stimulation. Similar differences were observed at the site of infection, where most cytokine concentrations were unchanged relative to controls. Our data are consistent with a model wherein TH1/TH17 differentiation is attenuated in NTM-infected children.