In this line, it has been demonstrated that uninfected Calu-6 constitutively produce high levels of TGF-β [38], and we observed that the infection with Mtb strains did not alter its production, as TGF-β is a potent anti-inflammatory mediator and its presence would be necessary to avoid an exacerbated innate immune response in the airway space [39]. The gene discussed is TGFB1; the disease is infection.