Díaz Carlos, Salát Jiří, Břínek Kolařová Dagmar, Celer Vladimír, Frébort Ivo
Czech Advanced Technology and Research Institute (CATRIN), Olomouc, Czech Republic.
Department of Biochemistry, Faculty of Science, Palacký University Olomouc, 779 00 Olomouc, Czech Republic.
J Vet Res. 2022 Aug 30;66(3):297-304. doi: 10.2478/jvetres-2022-0043. eCollection 2022 Sep.
The single member of the Asfarviridae family is African swine fever virus (ASFV). This double-stranded DNA virus infects wild and farmed swine and loses the pig industry large sums of money. An inner envelope, capsid, and outer envelope are parts of the ASFV particle containing structural proteins playing different roles in the process of infection or host immune defence evasion. When expressed by the baculovirus system, the p22 protein from the inner envelope was found to induce partial protection against a virulent virus strain. This study aimed to express a part of this protein in a different system and evaluate its immunogenicity.
We designed two proteins, the extracellular (C terminal) part of the p22 protein (p22Ct) and its fusion with the heat-labile enterotoxin B subunit from (LTB-p22Ct), which is supposed to be a potent enhancer of the immune response. Both proteins were produced in the expression system and subsequently used for mice immunisation to analyse their safety and immunogenicity.
The protein fused with LTB did not show the expected adjuvant properties and did not prove safe, because abscess formation was observed after immunisation. In contrast, immunisation with the p22Ct protein alone induced a higher antibody titre but caused no adverse symptoms.
These results show the high potential of the p22Ct region as an immunogenic protein for ASFV serological detection purposes.
非洲猪瘟病毒（ASFV）是非洲猪瘟病毒科的唯一成员。这种双链DNA病毒会感染野生猪和养殖猪，给养猪业造成巨大经济损失。非洲猪瘟病毒粒子由内膜、衣壳和外膜组成，其中的结构蛋白在感染过程或宿主免疫防御逃避过程中发挥着不同作用。当通过杆状病毒系统表达时，发现来自内膜的p22蛋白能诱导对强毒株产生部分保护作用。本研究旨在在不同系统中表达该蛋白的一部分，并评估其免疫原性。
我们设计了两种蛋白，即p22蛋白的胞外（C端）部分（p22Ct）及其与不耐热肠毒素B亚基的融合蛋白（LTB-p22Ct），后者被认为是一种有效的免疫反应增强剂。两种蛋白均在表达系统中产生，随后用于小鼠免疫，以分析其安全性和免疫原性。
与LTB融合的蛋白未表现出预期的佐剂特性，且经证实不安全，因为免疫后观察到有脓肿形成。相比之下，单独用p22Ct蛋白免疫诱导出更高的抗体滴度，但未引起不良症状。
这些结果表明，p22Ct区域作为一种免疫原性蛋白，在用于非洲猪瘟病毒血清学检测方面具有很高的潜力。
