Davenport M P, McKenzie K R, Basten A, Britton W J
Centenary Institute for Cancer Medicine and Cell Biology, University of Sydney, New South Wales, Australia.
Infect Immun. 1992 Mar;60(3):1170-7. doi: 10.1128/iai.60.3.1170-1177.1992.
The 70-kDa heat shock protein of Mycobacterium leprae has a high degree of homology with the human hsp70 protein, yet it still elicits T-lymphocyte responses in subjects infected with M. leprae or vaccinated with the related Mycobacterium bovis BCG. We examined the serological responses to this protein by using recombinant protein fragments expressed from mutants with deletions of the M. leprae p70 gene. Monoclonal antibodies raised against either M. bovis or M. leprae p70 reacted with the C-terminal fragments but not the N-terminal fragments in a solid-phase enzyme-linked immunosorbent assay and an immunoblot assay. Inhibition enzyme-linked immunosorbent assays confirmed that two separate epitopes were defined by these monoclonal antibodies. Murine polyclonal sera also showed stronger binding to the C-terminal fragments. Sera from 33 and 48% of lepromatous leprosy patients reacted with M. leprae and M. bovis p70. This reactivity was mycobacterium specific, since few sera from control subjects in the same leprosy-endemic region were seropositive. The levels of anti-mycobacterial hsp70 antibodies were higher in patients with lepromatous leprosy than in those with tuberculoid leprosy or tuberculosis. The reactivity of sera from patients with leprosy was maximal with the C-terminal fragments. Therefore the C-terminal portion of M. leprae hsp70, which includes the region of maximum divergence from human hsp70, is the major target for the humoral immune response to the protein.
麻风分枝杆菌的70 kDa热休克蛋白与人类hsp70蛋白具有高度同源性，但在感染麻风分枝杆菌或接种相关卡介苗的受试者中，它仍能引发T淋巴细胞反应。我们使用从麻风分枝杆菌p70基因缺失突变体表达的重组蛋白片段来检测对该蛋白的血清学反应。在固相酶联免疫吸附测定和免疫印迹测定中，针对牛分枝杆菌或麻风分枝杆菌p70产生的单克隆抗体与C末端片段反应，但不与N末端片段反应。抑制酶联免疫吸附测定证实这些单克隆抗体定义了两个独立的表位。小鼠多克隆血清也显示出与C末端片段更强的结合。33%和48%的瘤型麻风患者血清与麻风分枝杆菌和牛分枝杆菌p70发生反应。这种反应具有分枝杆菌特异性，因为在同一麻风流行地区的对照受试者中很少有血清呈阳性。瘤型麻风患者的抗分枝杆菌hsp70抗体水平高于结核样型麻风或结核病患者。麻风患者血清与C末端片段的反应性最强。因此，麻风分枝杆菌hsp70的C末端部分，包括与人hsp70差异最大的区域，是对该蛋白体液免疫反应的主要靶点。
