Defence mechanism against Coccidia using common antigens related with host cell invasion

球虫病是由属于顶复虫的细胞间原生动物引起的。在初次感染球虫后，宿主获得对再次感染的免疫力，目前正在努力鉴定能够诱导保护性宿主免疫反应的潜在疫苗抗原。为了鉴定参与宿主细胞侵袭的艾美耳球虫的潜在受体分子，制备了几种鸡acervulina （EA）单克隆抗体（mab）。其中一个单抗6D-12-G10识别EA孢子子的圆锥状抗原，并在体外显著抑制孢子子对cd8阳性T淋巴细胞的侵袭。此外，该单抗还与新孢子虫和弓形虫等密切相关的球虫寄生虫的速殖子具有交叉反应性。利用EA、e.b brunetti、e.c maxima、e.m ittis、e.c necatrix、e.p praecox和E.tenel等鸟类艾美耳球虫的孢子子，测定了其他单克隆抗体的种特异性和交叉反应性。单克隆抗体8E-1识别所有艾美耳球虫物种中存在的共同抗原决定因子，而单克隆抗体HE-4、8D-2和5D-11识别种间特异性表位。单克隆抗体8C-3鉴定出一个物种特异性表位。隐孢子虫属顶复门寄生虫的感染是目前公认的引起世界各地免疫健康和免疫功能低下的人和动物腹泻的原因。在本研究中，我们研究了这些鸡单克隆抗体与C.muris和c.m parvum的交叉反应性。通过间接免疫荧光检测，6D-12-G10能对一个47.9 kDa的蛋白进行强荧光染色，5D-11能对一个154.9 kDa的C.muris蛋白进行强荧光染色。单克隆抗体6D-12-G10和HE-4对细小梭菌孢子体呈强荧光染色。此外，在western blotting中，mab 6D-12-G10鉴定出一个47.9 kDa的小孢子虫蛋白。这些结果表明，其中一些单克隆抗体可能鉴定了一个共同的表位，该表位代表了顶复合体寄生虫的顶复合体。少

Coccidiosis is caused by intercellular protozoa belonging to apicomplexans. After initial infection with Coccidia, hosts acquire immunity to reinfection and much effort is currentry underway to identify potential vaccine antigens capable of inducing protective host immune response. In order to identify potential receptor molecules of Eimeria which are involved in host cell invasion, several chicken monoclonal antibodies (mAbs) against E.acervulina (EA) were developed. One of these mAbs, 6D-12-G10, recognized the conoid antigen of EA sporozoites and significantry inhibited sporozoite invasion of CD8-positive T lymphocytes in vitro. Furthermore, this mAb also showed cross-reactivity with tachyzoites from closely related coccidian parasite including Neospora and Toxoplasma. The species-specificity and cross-reactivity of other mAbs were determined using the sporozoites of several different avian Eimeria species including EA, E.brunetti, E.maxima, E.mitis, E.necatrix, E.praecox and E.tenel … More la. The mAb 8E-1 recognized a common antigenic determinant present on all Eimeria species whereas the mAbs HE-4, 8D-2 and 5D-11 recognized interspeciese-specific epitopes. The mAbs 8C-3 identified a species-specific epitope.The infection of Cryptosporidium parasites belonging to the phylum Apicomplexa is now a well recognized cause diarrhea in immunologically healthy and immunocompromised humans and animals throughout the world. In this study, we studied the cross-reactivity of these chicken mAbs with C.muris and C.Parvum. By indirect immunofluoreacsnt assay, 6D-12-G10 showed an intense fluorescent staining a 47.9 kDa protein, and mAbs 5D-11 identified a 154.9 kDa protein of C.muris. Mabs 6D-12-G10 and HE-4 showed an intense fluorescent staining on C.parvum sporozoites. Furthermore, in western blloting, mAbs 6D-12-G10 identified a 47.9 kDa protein of C.parvum. These results indicate that some of these mAbs may identify a common epitope which represent on the apical complex of the apicomplexan parasites. Less