de Yaniz M G, Moore D P, Odeón A C, Cano A, Cano D B, Leunda M R, Campero C M
Consejo Nacional de Investigaciones Científicas y Técnicas (CONICET), Argentina.
Vet Parasitol. 2007 Sep 30;148(3-4):213-8. doi: 10.1016/j.vetpar.2007.06.030. Epub 2007 Aug 13.
The aim of this study was to compare systemic humoral immune responses in pregnant heifers inoculated with Neospora caninum tachyzoites by conjunctival and intravenous routes. Twenty nine heifers separated in three experimental groups were studied: Group 1 (n=10 animals) and Group 2 (n=9 animals) were inoculated with 10(8) of N. caninum tachyzoites by conjunctival and intravenous routes at 5th month of gestation, respectively; Group 3 (n=10 animals) were non-inoculated control animals. An indirect fluorescent antibody test (IFAT) and western immunoblotting (IB) were used to analyze the humoral immune response. All animals from Group 1 developed N. caninum specific antibody responses after conjunctival inoculation recording the highest antibody titer (mean+/-SE: 160+/-49.9) at 6th month of gestation. There were statistical differences between humoral immune responses found in Group 1 and 2 being higher in the second one at 6.5th, 8.5th and 9th months of gestation (P<0.05). Interestingly, all heifers from Group 1 reverted to seronegative status at the end of gestation. No increase in antibody was detected in the uninfected control group. Same pattern of N. caninum antigens was recognized by sera from heifers inoculated by conjunctival route and heifers inoculated by intravenous route. Recognized antigens were 116, 92, 84, 77, 45, 40, 25-26 and 17-18 kDa. The conjunctival instillation of N. caninum tachyzoites in pregnant heifers induces specific systemic antibodies. Further work is needed in order to clarify the consequences of this novel experimental route of infection not only on the fetus but also on the dam.
本研究的目的是比较经结膜和静脉途径接种犬新孢子虫速殖子的妊娠小母牛的全身体液免疫反应。对分为三个实验组的29头小母牛进行了研究：第1组（n = 10头动物）和第2组（n = 9头动物）分别在妊娠第5个月经结膜和静脉途径接种10⁸个犬新孢子虫速殖子；第3组（n = 10头动物）为未接种的对照动物。采用间接荧光抗体试验（IFAT）和western免疫印迹法（IB）分析体液免疫反应。第1组所有动物经结膜接种后均产生了犬新孢子虫特异性抗体反应，在妊娠第6个月时抗体滴度最高（平均值±标准误：160±49.9）。第1组和第2组的体液免疫反应在妊娠第6.5、8.5和9个月时存在统计学差异，第2组的反应更高（P<0.05）。有趣的是，第1组的所有小母牛在妊娠末期均恢复为血清阴性状态。在未感染的对照组中未检测到抗体增加。经结膜途径接种的小母牛血清和经静脉途径接种的小母牛血清识别出相同模式的犬新孢子虫抗原。识别出的抗原为116、92、84、77、45、40、25 - 26和17 - 18 kDa。在妊娠小母牛中经结膜滴注犬新孢子虫速殖子可诱导特异性全身抗体。需要进一步开展工作，以阐明这种新的感染实验途径不仅对胎儿而且对母体的影响。
