HMOX1 and infection: In addition, the importance of HO-1 in human health is accentuated by HO-1 deficiency studies showing systemic inflammation, red blood cell fragility, intravascular hemolysis, hemorrhage, endothelial damage, asplenia, remarkable vulnerability to infection, high concentrations of extracellular heme, and early death (Kawashima et al., 2002, Radhakrishnan et al., 2011).