Wadee A A, Cohen J D, Rabson A R
Department of Immunology, South African Institute for Medical Research, Johannesburg.
Infect Immun. 1987 Nov;55(11):2777-82. doi: 10.1128/iai.55.11.2777-2782.1987.
In this study we examined the effects of Mycobacterium tuberculosis cell extracts on the phagocytic activity of polymorphonuclear leukocytes and cultured peripheral blood monocytes. M. tuberculosis cell extracts were fractionated on Sephacryl S-200 columns, and a 25-kilodalton glycolipoprotein was shown to inhibit the intracellular killing ability of these leukocytes but had no effect on their phagocytic potential. This same fraction inhibited fusion of phagosomes with lysosomes, as assessed by noting the transfer of acridine orange from lysosomes to phagosomes. This fraction was shown to have a maximal inhibitory effect when it was in the form of an intact carbohydrate-lipid-protein complex. Gamma interferon (IFN-gamma), but not IFN-alpha, reversed the inhibitory effect of the mycobacterial component on bactericidal activity and on fusion of phagosomes and lysosomes. Thus, this 25-kilodalton fraction of M. tuberculosis cell extract may be important in protecting organisms against phagocytic degradation, an effect which can be reversed by IFN-gamma.
在本研究中，我们检测了结核分枝杆菌细胞提取物对多形核白细胞和培养的外周血单核细胞吞噬活性的影响。结核分枝杆菌细胞提取物在Sephacryl S - 200柱上进行分级分离，结果显示一种25千道尔顿的糖脂蛋白可抑制这些白细胞的细胞内杀伤能力，但对其吞噬潜力没有影响。通过观察吖啶橙从溶酶体向吞噬体的转移来评估，该级分同样抑制吞噬体与溶酶体的融合。当该级分为完整的碳水化合物 - 脂质 - 蛋白质复合物形式时，显示出最大抑制作用。γ干扰素（IFN - γ）而非α干扰素可逆转分枝杆菌成分对杀菌活性以及吞噬体与溶酶体融合的抑制作用。因此，结核分枝杆菌细胞提取物的这种25千道尔顿级分在保护生物体免受吞噬降解方面可能很重要，而γ干扰素可逆转这种作用。
