Vernati G, Edwards W H, Rocke T E, Little S F, Andrews G P
Department of Veterinary Sciences, University of Wyoming, Laramie, Wyoming 82070, USA.
J Wildl Dis. 2011 Jan;47(1):21-9. doi: 10.7589/0090-3558-47.1.21.
Although Yersinia pestis is classified as a "high-virulence" pathogen, some host species are variably susceptible to disease. Coyotes (Canis latrans) exhibit mild, if any, symptoms during infection, but antibody production occurs postinfection. This immune response has been reported to be against the F1 capsule, although little subsequent characterization has been conducted. To further define the nature of coyote humoral immunity to plague, qualitative serology was conducted to assess the antiplague antibody repertoire. Humoral responses to six plasmid-encoded Y. pestis virulence factors were first examined. Of 20 individual immune coyotes, 90% were reactive to at least one other antigen in the panel other than F1. The frequency of reactivity to low calcium response plasmid (pLcr)-encoded Yersinia protein kinase A (YpkA) and Yersinia outer protein D (YopD) was significantly greater than that previously observed in a murine model for plague. Additionally, both V antigen and plasminogen activator were reactive with over half of the serum samples tested. Reactivity to F1 was markedly less frequent in coyotes (35%). Twenty previously tested antibody-negative samples were also examined. While the majority were negative across the panel, 15% were positive for 1-3 non-F1 antigens. In vivo-induced antigen technology employed to identify novel chromosomal genes of Y. pestis that are up-regulated during infection resulted in the identification of five proteins, including a flagellar component (FliP) that was uniquely reactive with the coyote serum compared with immune serum from two other host species. Collectively, these data suggest that humoral immunity to pLcr-encoded antigens and the pesticin plasmid (pPst)-encoded Pla antigen may be relevant to plague resistance in coyotes. The serologic profile of Y. pestis chromosomal antigens up-regulated in vivo specific to C. latrans may provide insight into the differences in the pathogen-host responses during Y. pestis infection.
尽管鼠疫耶尔森菌被归类为“高毒力”病原体，但一些宿主物种对该疾病的易感性存在差异。郊狼（犬属）在感染期间即使有症状也很轻微，不过感染后会产生抗体。据报道，这种免疫反应针对的是F1荚膜，尽管后续几乎没有进行特征描述。为了进一步确定郊狼对鼠疫的体液免疫性质，进行了定性血清学检测以评估抗鼠疫抗体库。首先检测了对六种由质粒编码的鼠疫耶尔森菌毒力因子的体液反应。在20只具有免疫能力的郊狼中，90%对检测组中除F1之外的至少一种其他抗原产生反应。对低钙反应质粒（pLcr）编码的耶尔森菌蛋白激酶A（YpkA）和耶尔森菌外膜蛋白D（YopD）产生反应的频率显著高于先前在鼠疫小鼠模型中观察到的频率。此外，V抗原和纤溶酶原激活剂与超过一半的检测血清样本发生反应。郊狼对F1产生反应的频率明显较低（35%）。还检测了20个先前检测为抗体阴性的样本。虽然大多数样本在整个检测组中均为阴性，但15%对1 - 3种非F1抗原呈阳性。采用体内诱导抗原技术来鉴定鼠疫耶尔森菌在感染期间上调的新染色体基因，结果鉴定出了五种蛋白质，其中包括一种鞭毛成分（FliP），与来自其他两种宿主物种的免疫血清相比，它与郊狼血清具有独特的反应性。总体而言，这些数据表明，对pLcr编码抗原和鼠疫菌素质粒（pPst）编码的Pla抗原的体液免疫可能与郊狼对鼠疫的抗性有关。鼠疫耶尔森菌染色体抗原在体内针对郊狼上调的血清学特征，可能有助于深入了解鼠疫耶尔森菌感染期间病原体 - 宿主反应的差异。
