M tuberculosis infection is not affected by hepcidin deficiency or iron loading in mice. Control WT mice, naturally iron-loaded HKO mice, and parenterally iron-loaded WT mice (iron-dextran injection, WT + ID) were infected with 30 CFUs of M tuberculosis (aerosol). After 5 and 10 weeks, there was no difference between the 3 groups of mice in pulmonary (A) or extrapulmonary (B) bacterial burden as assessed by tissue CFUs. (C-D) Lung and spleen iron concentration. Statistical analysis: Student t test if data were normally distributed (C: WT vs HKO 5 weeks, WT vs WT+ID 10 weeks; D: WT vs HKO, 5 weeks) and Mann-Whitney U test if they were not normally distributed.