[Impacts of Mycobacterium tuberculosis with different virulence on expressions of ferroportin and ferritin in infected macrophages].

To explore the time-dependent changes in the expressions of ferritin (Fn) and ferroportin (FPN) in macrophages infected with Mycobacterium (M.) tuberculosis of highly virulent strain (H37Rv strain) and Bacillus Calmette-Guerin (BCG) strain. RAW264.7 macrophages were respectively infected with M. tuberculosis H37Rv strain and BCG strain. At 1, 6, 12, 18 and 24 h after infection, the contents of Fn and FPN in the infected macrophage culture supernatants of the two groups were detected using ELISA, and meanwhile, the expression of Fn in the infected macrophages of each group was determined using Western blotting. After the macrophages were infected with different strains, the expression of Fn in macrophages increased as time went by; at 1 h after infection, the Fn expression in the control group was significantly higher than that in the H37Rv group and the BCG group; at 6 h after infection, the Fn expression in the two infected groups were higher than that in the control group; at 12 h, the Fn expression in the H37Rv group was higher than that in the control group, the difference was statistically significant (P<0.05); at 18 and 24 h, the Fn expression was reduced in the order as H37Rv group > BCG group > control group (P<0.05). The expression of FPN decreased gradually as time went by. Compared with the normal control group, the expression in both H37Rv group and BCG group presented a lower level and H37Rv group < BCG group < control group (P<0.05). The infection of M.tuberculosis can lead to increased Fn expression and decreased FPN expression in macrophages, and the levels of Fn and FPN in the infected macrophages are both related to the strength of the virulence of M.tuberculosis.