HMOX1 and tuberculosis: Further, •NO and CO, produced by nitric oxide synthase II (iNOS) and heme oxygenase 1 (HO-1), respectively, are important host factors that can alter Mtb survival and TB disease progression (MacMicking et al., 1997a; MacMicking et al., 1997b; Kumar et al., 2007; Kumar et al., 2008; Chinta et al., 2016; Chinta et al., 2018).