Loa C C, Lin T L, Wu C C, Bryan T, Thacker H L, Hooper T, Schrader D
Department of Veterinary Pathobiology, Purdue University, West Lafayette, Indiana 47907-1175, USA.
Poult Sci. 2001 Oct;80(10):1416-24. doi: 10.1093/ps/80.10.1416.
The objective of the present study was to elucidate the kinetics of humoral and cellular immune responses of turkey poults infected with turkey coronavirus (TCV). Turkey poults were orally inoculated with TCV at 10 d of age, and the immune responses were analyzed at 1, 3, 7, 14, 21, 28, 42, and 63 d postinfection (PI) in three different experiments. Total Ig to TCV was initially detected at 7 and 14 d PI in Experiments 1 and 3. In addition, Ig gradually increased from 7 to 21 d PI and remained at 80 immunofluroescent antibody assay (IFA) titers or more thereafter. Lymphocyte proliferation responses of spleen cells to concanavalin A were higher in TCV-infected turkeys than in noninfected control turkeys with significant differences (P < 0.05) being noted at 14 and 63 d PI in Experiment 2 and at 3 and 28 d PI in Experiment 3. Strong IFA staining response to TCV antigen was observed in intestines of turkeys at 1, 3, and 7 d PI, and the response declined from 14 to 28 d PI in Experiment 3. In Experiment 3, the IgG isotype antibody response to TCV was markedly increased after 21 d PI and remained high until 63 d PI. The IgM isotype antibody response to TCV was 1.40 and 0.91 at 7 and 14 d PI, respectively. The IgA isotype antibody response to TCV was very low as detected at 7 (0.13), 14 (0.20), and 21 (0.17) d PI. Turkeys infected with TCV had significantly higher (P < 0.05) antibody response to sheep erythrocytes than noninfected controls at 7 d PI. Virus-specific lymphocyte proliferation response of spleen cells was significantly stimulated (P < 0.05) at 63 d PI in Experiment 3. The proportion of the CD4+ subpopulation of T lymphocytes was significantly increased (P < 0.05) at 1, 7, and 21 d PI in Experiment 3. The results indicate that humoral and cellular immunities to TCV are elicited in turkeys following infection with TCV.
本研究的目的是阐明感染火鸡冠状病毒（TCV）的幼火鸡体液免疫和细胞免疫反应的动力学。在10日龄时给幼火鸡口服接种TCV，并在三个不同的实验中于感染后（PI）1、3、7、14、21、28、42和63天分析免疫反应。在实验1和实验3中，感染后7天和14天首次检测到针对TCV的总Ig。此外，Ig在感染后7至21天逐渐增加，此后在免疫荧光抗体测定（IFA）中的效价保持在80或更高。在实验2中，感染TCV的火鸡脾脏细胞对刀豆蛋白A的淋巴细胞增殖反应高于未感染的对照火鸡，在感染后14天和63天以及实验3中感染后3天和28天观察到显著差异（P<0.05）。在实验3中，在感染后1、3和7天观察到火鸡肠道对TCV抗原的强烈IFA染色反应，且在感染后14至28天反应下降。在实验3中，感染后21天对TCV的IgG同种型抗体反应显著增加，并一直保持高水平直至感染后63天。在感染后7天和14天，对TCV的IgM同种型抗体反应分别为1.40和0.91。在感染后7天（0.13）、14天（0.20）和21天（0.17）检测到对TCV的IgA同种型抗体反应非常低。在感染后7天，感染TCV的火鸡对绵羊红细胞的抗体反应显著高于未感染的对照（P<0.05）。在实验3中，感染后63天脾脏细胞的病毒特异性淋巴细胞增殖反应受到显著刺激（P<0.05）。在实验3中，感染后1、7和21天，T淋巴细胞CD4+亚群的比例显著增加（P<0.05）。结果表明，火鸡感染TCV后会引发对TCV的体液免疫和细胞免疫。
