Avian Immunosuppressive Diseases Division, State Key Laboratory of Veterinary Biotechnology, Harbin Veterinary Research Institute, The Chinese Academy of Agricultural Sciences, Harbin, 150069, P. R. China.
Departments of Radiology, Second Affiliated Hospital, Harbin Medical University, Harbin, 150001, China.
Vet Res. 2020 Oct 19;51(1):133. doi: 10.1186/s13567-020-00857-y.
Reticuloendotheliosis is an important immunosuppressive disease, associated with avian reticuloendotheliosis virus (REV) infection, and causes notable economic losses worldwide. Glycoprotein gp90 is an important structural protein of REV, and considered to be the most important immunogenic antigen, which can induce neutralizing antibodies against REV. In this study, an optimized suspension culture system was developed and applied to secretory express the immunogenic surface antigen gp90. To achieve an optimal glycosylation, the gp90 was designed to secretory expressed into the supernatant of the cell culture, which also occurs in the natural protein maturation procedure of REV. Serum-free culture medium was introduced to simplify the purification process and reduce the production costs. Based on the purified glycosylated gp90, an oil-emulsion subunit REV vaccine candidate was developed and evaluated in chickens. The subunit gp90-based vaccine induced fast immune responses, high levels of antibodies (REV-specific antibody, gp90-specific antibody, and neutralizing antibody against REV), and preferential T helper 2 (Th2) (interleukin-4 secretion) not Th1 (interferon-γ secretion) response. Furthermore, the viremia induced by REV infection was significantly reduced in chickens immunized with the glycosylated gp90. Overall, an optimized secretory expression system for glycosylated gp90 was developed, and the glycosylated gp90 obtained in this study retained good immunogenicity and could be an attractive vaccine candidate to protect chickens against REV horizonal infection.
网状内皮组织增生病是一种重要的免疫抑制性疾病，与禽网状内皮组织增生病毒（REV）感染有关，给全球范围内造成了显著的经济损失。糖蛋白 gp90 是 REV 的一种重要结构蛋白，被认为是最重要的免疫原性抗原，能够诱导针对 REV 的中和抗体。在本研究中，开发了一种优化的悬浮培养系统，并将其应用于免疫原性表面抗原 gp90 的分泌表达。为了实现最佳糖基化，设计了 gp90 分泌表达到细胞培养物的上清液中，这也是 REV 天然蛋白成熟过程中的情况。引入无血清培养基以简化纯化过程并降低生产成本。基于纯化的糖基化 gp90，开发并评估了一种油乳剂亚单位 REV 疫苗候选物在鸡中的应用。基于亚单位 gp90 的疫苗诱导了快速的免疫反应，产生了高水平的抗体（REV 特异性抗体、gp90 特异性抗体和针对 REV 的中和抗体），并优先诱导 T 辅助 2（Th2）（白细胞介素-4 分泌）而不是 Th1（干扰素-γ 分泌）反应。此外，接种糖基化 gp90 的鸡中由 REV 感染引起的病毒血症显著减少。总体而言，开发了一种用于糖基化 gp90 的优化分泌表达系统，本研究中获得的糖基化 gp90 保留了良好的免疫原性，可能是一种有吸引力的疫苗候选物，可用于保护鸡免受 REV 水平感染。
