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

球虫病是由属于尖端复合体的细胞间原虫引起的。初次感染球虫后，宿主获得对再次感染的免疫力，目前正在进行大量工作，以确定能够诱导保护性宿主免疫反应的潜在疫苗抗原。为了确定可能参与宿主细胞入侵的艾美耳球虫受体分子，研制了几种鸡抗艾美耳球虫(Ea)的单抗。其中一种单抗6D-12-G10识别EA子孢子的锥形抗原，并在体外显著抑制子孢子对CD8阳性T淋巴细胞的侵袭。此外，该单抗还能与新孢子虫和弓形虫等近缘球虫的速殖子发生交叉反应。用几种不同禽种的艾美耳球虫的子孢子，包括EA、E.brunetti、E.max、E.mitis、E.Necatrix、E.preecox和E.tenel…，测定了其他单抗的种特异性和交叉反应性。更多的洛杉矶。单抗8E-1识别存在于所有艾美耳球虫物种上的共同抗原决定簇，而单抗HE-4、8D-2和5D-11识别种间特异性表位。MAb8C-3确定了一个物种特异性的表位。属于尖端复合门的隐孢子虫寄生虫的感染现在是全世界免疫健康和免疫受损的人和动物的腹泻的公认原因。在这项研究中，我们研究了这些鸡单抗与C.Muris和C.parvum的交叉反应。通过间接免疫荧光试验，6D-12-G10表达了47.9kDa的蛋白，mAb5D-11表达了154.9 kDa的蛋白。单抗6D-12-G10和HE-4对微小隐孢子虫子孢子有较强的荧光染色。此外，在Western blotting中，mAb6D-12-G10鉴定了一种47.9 kDa的微小隐孢子虫蛋白。这些结果表明，这些单抗中的一些可能识别了代表顶端复合体寄生虫顶端复合体的共同表位。较少

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