Tennyson S A, Barta J R
Department of Pathobiology, Ontario Veterinary College, University of Guelph, Canada.
Parasitol Res. 2000 Jun;86(6):453-60. doi: 10.1007/s004360050693.
A low molecular weight (LMW) antigen recognized by a murine monoclonal antibody (C(3)4F(1)) was localized within endogenous stages of Eimeria tenella (USDA strain 80). Using indirect fluorescent antibody assay and immunoelectron microscopy, the LMW antigen was found in: sporozoites, first, second and third generation meronts, gamonts, unsporulated oocysts, and sporocysts. The antigen was observed in the cytoplasm and pellicle of the parasite, and in the parasitophorous vacuole, sporocyst walls and cytoplasm of infected host cells. The immunogenicity of this LMW antigen was assessed by antigen-specific serum antibody responses in chickens orally inoculated with live oocysts or injected intramuscularly with dead sporozoites. LMW antigen-specific serum antibodies were detected using Western blots of E. tenella sporozoites as early as 4 days after sporozoite injection and 6 days after oocyst inoculation. Unusually, the monoclonal antibody C(3)4F(1) reduced the binding of immune chicken serum to the antigen in a competitive antibody binding assay, but not the reverse, suggesting that there is a single, immunodominant epitope on this antigen.
一种可被鼠单克隆抗体（C(3)4F(1)）识别的低分子量（LMW）抗原定位于柔嫩艾美耳球虫（美国农业部80株）的内源性发育阶段。通过间接荧光抗体试验和免疫电子显微镜观察发现，该低分子量抗原存在于：子孢子、第一代、第二代和第三代裂殖体、配子体、未孢子化卵囊和孢子囊。在寄生虫的细胞质和表膜、以及被感染宿主细胞的寄生泡、孢子囊壁和细胞质中均观察到该抗原。通过对口服接种活卵囊或肌肉注射死子孢子的鸡体内抗原特异性血清抗体反应，评估了该低分子量抗原的免疫原性。早在注射子孢子后4天和接种卵囊后6天，利用柔嫩艾美耳球虫子孢子的蛋白质免疫印迹法检测到了低分子量抗原特异性血清抗体。异常的是，在竞争性抗体结合试验中，单克隆抗体C(3)4F(1)降低了免疫鸡血清与该抗原的结合，但反之则不然，这表明该抗原上存在单一的免疫显性表位。
