Stierhof Y D, Schwarz H, Menz B, Russell D G, Quinten M, Overath P
Max-Planck-Institut für Biologie, Tübingen, Federal Republic of Germany.
J Cell Sci. 1991 May;99 ( Pt 1):181-6. doi: 10.1242/jcs.99.1.181.
In the accompanying paper by Ilg et al., it was shown that Leishmania mexicana promastigotes covalently modify a secreted acid phosphatase and other proteins by carbohydrate epitopes characteristic for lipophosphoglycan (LPG). In this study, the reaction of the anti-LPG monoclonal antibodies (mAbs AP3 and L7.25) and of mAb L3.13, an antibody directed against an epitope present on the secreted acid phosphatase but not on LPG, with promastigotes and infected peritoneal macrophages is studied by immunofluorescence and immunoelectron microscopy. AP3 labels the surface, the flagellar pocket and intracellular structures in promastigotes, while L3.13 reacts predominantly with an antigen located in the flagellar pocket. Early after infection with promastigotes, but not amastigotes, AP3 or L7.25 transiently label epitopes at the surface of live macrophages. No L3.13-reactive material is detected at the surface of infected macrophages. In permeabilized, infected macrophages, AP3 heavily labels the surface of amastigotes and the lumen of the parasitophorous vacuole, while L3.13 reveals antigen in the flagellar pocket, intracellular vesicles of amastigotes, and components in the lumen of the parasitophorous vacuole. Possible mechanistic implications for Leishmania-macrophage interaction raised by these findings are discussed.
在伊尔格等人的相关论文中，已表明墨西哥利什曼原虫前鞭毛体通过脂磷壁酸（LPG）特有的碳水化合物表位共价修饰一种分泌型酸性磷酸酶和其他蛋白质。在本研究中，通过免疫荧光和免疫电子显微镜研究了抗LPG单克隆抗体（mAb AP3和L7.25）以及mAb L3.13（一种针对分泌型酸性磷酸酶上存在但LPG上不存在的表位的抗体）与前鞭毛体和感染的腹腔巨噬细胞的反应。AP3标记前鞭毛体的表面、鞭毛囊和细胞内结构，而L3.13主要与位于鞭毛囊中的一种抗原发生反应。在用前鞭毛体感染后早期，但不是无鞭毛体感染后早期，AP3或L7.25短暂标记活巨噬细胞表面的表位。在感染的巨噬细胞表面未检测到L3.13反应性物质。在通透的感染巨噬细胞中，AP3大量标记无鞭毛体的表面和寄生泡的腔，而L3.13揭示鞭毛囊、无鞭毛体的细胞内小泡以及寄生泡腔中的成分中有抗原。讨论了这些发现对利什曼原虫 - 巨噬细胞相互作用可能的机制影响。
