Fig 3. B cell-deficient μMT mice exhibit diminished levels of IFN-γ-producing CD4⁺ T cells during chronic TB.

Mice were infected with 100 CFU of M. tuberculosis Erdman by aerosolization. (A) Representative frequencies of IFN-γ⁺ CD4⁺ T cells detected by flow cytometry at 5 months after infection; n = 4 mice per group. (B) Absolute number of lung IFN-γ⁺ CD4⁺ T cells detected 5 months after infection; n = 4 mice per group. The results are expressed as mean ± SEM. Data in this figure is representative of 3 similar experiments. The data show revealed the B cell-deficient μMT mice, relative to WT, display an attenuated Th1 response during the chronic phase of tuberculous infection.