Canine parvovirus type 2 (CPV-2) is one of the most common causes of infectious diarrhea in small animals, with high mortality and morbidity. Information on the specific treatment option(s) for CPV diseases (CPVD) is unachievably little. So, the treatment is mainly supportive one. Disruption of dog's innate immune system in viral diseases simply occurs; presumably, the CPV-2 may change the level of some TLRs, interleukins, CD4 and CD8 in the leukocytes of CPVD dogs, and disruptive activities of these immune molecules might be attributable to severe CPVD in dogs. Study on the role of the key immune molecules in CPVD is rare. Herein, by conducting and relating the clinical, para-clinical, immunological and molecular diagnostic tests, we tried to establish how some key immune molecules behave in blood of parvovirus affected dogs. As such, in the 1st study, the mRNA levels of TLR2, TLR4, TLR9, IL-1β, IL-6, CD4 and CD8 genes in the leukocytes of CPVD were assessed with quantitative (q)RT-PCR along with CPV-2 detection by rapid immunochromatography and PCR tests. In a 2nd study, the same measurements as in the 1st study were evaluated in two groups of mild versus severe clinical signs of CPVD. Both in the 1st and the 2nd studies leukopenia, much more pronounced in the severe CPVD, and immune dysregulation were observed. In the 1st study, a noticeable increase in the mRNA levels of TLR2 and TLR4 was detected with a slight decrease in TLR9 and a significant decrease in the expression of IL-1β, IL-6, CD4 and CD8 in leukocytes of CPV-infected dogs. Compared to the mild CPVD, the intense of downregulating effects on those immune molecules in the 2nd study was remarkably much more pronounced in the severe CPVD. Overall, it proves strong immune dysregulation and suppression/incompetence and potential T-cells exhaustion in severely CPV-2-affected dogs. Technically and clinically, this would be substantially applicable in canine medicine. By targeting those key immune molecules and their signaling pathways, new clinicodiagnostic approaches for CPVD can be evolved, and biotechnicoclinically this would be substantially applicable in all physiopathological conditions of dogs.

2 型犬细小病毒 (CPV-2) 是小动物感染性腹泻的最常见原因之一，具有很高的死亡率和发病率。关于 CPV 疾病 (CPVD) 的具体治疗方案的信息非常少。因此，治疗主要以支持性治疗为主。病毒性疾病会破坏狗的先天免疫系统；据推测，CPV-2可能会改变CPVD狗白细胞中一些TLR、白细胞介素、CD4和CD8的水平，而这些免疫分子的破坏性活动可能归因于狗的严重CPVD。关于 CPVD 中关键免疫分子的作用的研究很少。在此，通过进行和关联临床、临床旁、免疫学和分子诊断测试，我们试图确定一些关键免疫分子在细小病毒感染的狗的血液中的行为。因此，在第一项研究中，通过定量 (q)RT-PCR 和 CPV-2 评估了 CPVD 白细胞中 TLR2、TLR4、TLR9、IL-1β、IL-6、CD4 和 CD8 基因的 mRNA 水平。通过快速免疫层析和PCR检测进行检测。在第二项研究中，对两组轻度和重度 CPVD 临床症状进行了与第一项研究相同的测量。在第 1 项和第 2 项研究中，均观察到白细胞减少症（在严重 CPVD 中更为明显）和免疫失调。在第一项研究中，检测到 CPV 感染犬白细胞中 TLR2 和 TLR4 mRNA 水平显着增加，TLR9 略有下降，IL-1β、IL-6、CD4 和 CD8 表达显着下降。与轻度 CPVD 相比，第二项研究中这些免疫分子的强烈下调作用在重度 CPVD 中要明显得多。总体而言，它证明了严重感染 CPV-2 的狗存在严重的免疫失调和抑制/无能以及潜在的 T 细胞耗竭。从技术上和临床上来说，这将在很大程度上适用于犬科医学。通过针对这些关键的免疫分子及其信号通路，可以开发出新的 CPVD 临床诊断方法，并且从生物技术临床角度来看，这将基本上适用于狗的所有病理生理状况。