CD4 and tuberculosis: Comparing the lung inflammatory response in chronic TB of WT C57BL/6’s with that of their B cell-deficient counterparts [34,35], the present study has provided evidence that in chronic TB, B cells i) can contribute, at least in part, to the development of pulmonic inflammation by enhancing the levels of the protective and pro-inflammatory IFN-γ-producing CD4+ T cells in the lungs [9,36]; ii) this Th1 augmentation may be due to the ability of B cells to restrict the expression of the immunoregulatory IL-10 that possesses immunosuppressive and anti-inflammatory properties [37–40].