Characterization of bovine cellular and serum antibody responses during infection by Cryptosporidium parvum
Characterization of bovine cellular and serum antibody responses during infection by Cryptosporidium parvum
复制标题
小隐孢子虫感染期间牛细胞和血清抗体反应的特征
作者：
W. Whitmire;J. Harp
在给小牛口服接种小隐孢子虫卵囊后 23 天，监测小牛的细胞和血清抗体反应。在用微小念珠菌制剂刺激后，评估外周血淋巴细胞的体外成胚反应。接种后2天检测到针对寄生虫的特异性淋巴细胞胚细胞反应。寄生虫特异性抗体滴度在接种卵囊后 7 天即可显现，并在接种后 9 天达到峰值水平，与接种后 5 至 10 天卵囊脱落一致。淋巴细胞和抗体反应均保持升高直至实验结束。用感染小牛的血清对微小隐球菌制剂进行免疫印迹，结果显示六种主要寄生虫抗原。接种卵囊后 7 至 14 天，其中 5 种抗原在免疫印迹上发生反应。接种后 7 至 23 天，分子量约为 11,000 的寄生虫抗原在免疫印迹上表现出强烈的反应性。 11,000 分子量的抗原也在免疫印迹上与肠胃外产生的抗卵囊和抗子孢子兔血清发生反应。这些结果表明，细胞介导的以及体液免疫反应是由小牛中的隐孢子虫感染引发的，并且 11,000 分子量的寄生虫抗原具有免疫显性。
Cellular and serum antibody responses of calves were monitored for 23 days after oral inoculation of the calves with oocysts of Cryptosporidium parvum. In vitro blastogenic responses of peripheral blood lymphocytes were assessed after stimulation with a C. parvum preparation. Specific lymphocyte blastogenic responses to the parasite were detected 2 days after inoculation. Parasite-specific antibody titers were demonstrable 7 days after inoculation with oocysts and achieved peak levels 9 days after inoculation, coinciding with oocyst shedding at 5 to 10 days after inoculation. Both lymphocyte and antibody responses remained elevated until the termination of the experiment. Immunoblotting the C. parvum preparation with serum from an infected calf revealed six major parasite antigens. Five of these antigens reacted on immunoblots from 7 to 14 days after inoculation with oocysts. A parasite antigen of approximately 11,000 molecular weight demonstrated intense reactivity on immunoblots from 7 to 23 days after inoculation. The 11,000-molecular-weight antigen also reacted on immunoblots with parenterally raised antioocyst and antisporozoite rabbit sera. These results indicate that cell-mediated as well as humoral immune responses are initiated by cryptosporidial infection in calves and that the 11,000-molecular-weight parasite antigen is immunodominant.