Einfeld D A, Stibbs H H
Infect Immun. 1984 Nov;46(2):377-83. doi: 10.1128/iai.46.2.377-383.1984.
The surface antigens of Giardia lamblia trophozoites were characterized by crossed immunoelectrophoresis, radioiodination, and immunoprecipitation. Crossed immunoelectrophoretic analysis of trophozoites with hyperimmune rabbit anti-trophozoite antiserum revealed a prominent precipitin peak that disappeared upon adsorption of the antiserum with live or formaldehyde-fixed trophozoites. This peak was intensely labeled when the antigen was derived from surface-radioiodinated trophozoites. An antiserum monospecific for the antigen contained in this precipitin peak was prepared. The precipitin peak was shown to contain an antigen with an apparent molecular weight of 82,000 by Western blotting. The antiserum also detected this 82,000-molecular-weight antigen on nitrocellulose blots of trophozoites analyzed by sodium dodecyl sulfate-polyacrylamide gel electrophoresis. On radioiodination of live trophozoites, an iodinated molecule of 82,000 apparent molecular weight was resolved by sodium dodecyl sulfate-polyacrylamide gel electrophoresis and was immunoprecipitated by the monospecific antiserum. Preliminary characterization of this antigen with the monospecific antiserum in crossed immunoelectrophoresis revealed that the surface antigen is hydrophobic and thus may be anchored in the plasma membrane, and that it is heat sensitive, but only partially sensitive to pronase or periodate. This antigen was shared by the four G. lamblia strains examined.
通过交叉免疫电泳、放射性碘化和免疫沉淀法对蓝氏贾第鞭毛虫滋养体的表面抗原进行了表征。用超免疫兔抗滋养体抗血清对滋养体进行交叉免疫电泳分析，结果显示一个突出的沉淀素峰，当用活的或甲醛固定的滋养体吸附抗血清后，该峰消失。当抗原来源于经表面放射性碘化的滋养体时，这个峰被强烈标记。制备了针对该沉淀素峰中所含抗原的单特异性抗血清。通过蛋白质印迹法显示，该沉淀素峰含有一种表观分子量为82,000的抗原。该抗血清在十二烷基硫酸钠-聚丙烯酰胺凝胶电泳分析的滋养体硝酸纤维素印迹上也检测到了这种82,000分子量的抗原。对活滋养体进行放射性碘化后，通过十二烷基硫酸钠-聚丙烯酰胺凝胶电泳分离出一种表观分子量为82,000的碘化分子，并被单特异性抗血清免疫沉淀。在交叉免疫电泳中用单特异性抗血清对该抗原进行初步表征，结果显示该表面抗原具有疏水性，因此可能锚定在质膜中，并且它对热敏感，但仅对链霉蛋白酶或高碘酸盐部分敏感。所检测的4株蓝氏贾第鞭毛虫均具有这种抗原。
