Douvas G S, May M H, Crowle A J
Webb-Waring Lung Institute, Division of Immunology, University of Colorado School of Dentistry, Denver 80262.
J Infect Dis. 1993 Apr;167(4):857-64. doi: 10.1093/infdis/167.4.857.
Mycobacterium avium grows exponentially over 7 days in human macrophages when they are cultured in serumless medium. Normal serum inhibits this replication. When serum lipids were extracted using chloroform, the inhibitor was present in the lipid-free component. The lipid extract significantly enhanced M. avium replication. Iron (Fe2+) added at 8-80 micrograms/mL to infected macrophage cultures in serum resulted in enhanced mycobacterial replication. Serum-induced inhibition of bacterial growth in serumless medium could be duplicated with apotransferrin at 50-500 micrograms/mL. At 1000 micrograms/mL, apotransferrin no longer inhibited bacterial growth. Holotransferrin was not inhibitory, and at 500 micrograms/mL, it enhanced M. avium growth. Depletion of the transferrin in serum by affinity chromatography using goat anti-transferrin on protein G-Sepharose removed inhibitory activity. These results indicate that transferrin levels, transferrin saturation, iron levels, and serum lipids can profoundly alter the replication of M. avium in association with macrophages.
鸟分枝杆菌在无血清培养基中培养时，在人类巨噬细胞内7天呈指数生长。正常血清可抑制这种增殖。当用氯仿提取血清脂质时，抑制剂存在于无脂质成分中。脂质提取物显著增强了鸟分枝杆菌的增殖。向血清中感染巨噬细胞培养物中添加8 - 80微克/毫升的铁（Fe2+）可导致分枝杆菌增殖增强。无血清培养基中血清诱导的细菌生长抑制作用可被50 - 500微克/毫升的脱铁转铁蛋白复制。在1000微克/毫升时，脱铁转铁蛋白不再抑制细菌生长。全转铁蛋白无抑制作用，在500微克/毫升时，它增强了鸟分枝杆菌的生长。使用蛋白G - 琼脂糖上的山羊抗转铁蛋白通过亲和层析耗尽血清中的转铁蛋白可去除抑制活性。这些结果表明，转铁蛋白水平、转铁蛋白饱和度、铁水平和血清脂质可与巨噬细胞相关联地深刻改变鸟分枝杆菌的增殖。
