Infectious laryngotracheitis virus (ILTV) is a cause of main respiratory disease of chickens controlled through live attenuated vaccines. To reduce the risk of adverse effects associated with live vaccines, a recombinant vaccine expressing PH-1 domain of viral glycoprotein B was constructed using the pET expression system under isopropylthiogalactoside (IPTG) induction. The potential immunogenicity of recombinant PH-1 (rPH-1) was evaluated in chickens. Eight-week-old specific-pathogen-free chickens were intramuscularly administered two doses of rPH-1, 25 and 50 μg, alone or with a combination of ISA70 adjuvant. The humoral immune responses were determined up to 3 months postvaccination at 2 weeks apart. The T cell proliferation response was determined on day 28 after primary immunization. The vaccinated birds with rPH-1/ISA70 developed higher and constant-specific anti-ILTV enzyme-linked immunosorbent assay (ELISA) antibodies than in those vaccinated with rPH-1 alone. Coinjection of rPH-1 and adjuvant significantly (p < 0.01) increased the T cell proliferation responses. There were no significant differences in eliciting the immune responses in chickens immunized with the higher dose of the antigen than that with the lower dose. The data indicate the immunogenic efficiency of rPH-1 against ILTV. Vaccination with recombinant proteins offers a preventing option to control the ILTV infection and could be a candidate to replace current live vaccines.

中文翻译：

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鸡传染性喉气管炎病毒糖蛋白 B 重组 PH-1 结构域对免疫反应的诱导

传染性喉气管炎病毒 (ILTV) 是通过减毒活疫苗控制的鸡的主要呼吸道疾病的原因。为了降低与活疫苗相关的不良反应的风险，在异丙基硫代半乳糖苷 (IPTG) 诱导下，使用 pET 表达系统构建了表达病毒糖蛋白 B 的 PH-1 结构域的重组疫苗。在鸡中评估了重组 PH-1 (rPH-1) 的潜在免疫原性。八周龄无特定病原体的鸡肌肉内注射两剂 rPH-1、25 和 50 μg，单独或与 ISA70 佐剂联合使用。体液免疫反应在疫苗接种后长达 3 个月时相隔 2 周测定。在初次免疫后第 28 天测定 T 细胞增殖反应。与单独接种 rPH-1 的鸡相比，接种 rPH-1/ISA70 的鸡产生了更高且恒定特异性的抗 ILTV 酶联免疫吸附试验 (ELISA) 抗体。rPH-1 和佐剂的联合注射显着 (p  < 0.01) 增加了 T 细胞增殖反应。用较高剂量的抗原免疫鸡与用较低剂量免疫的鸡在引发免疫反应方面没有显着差异。数据表明 rPH-1 对 ILTV 的免疫原性效率。用重组蛋白进行疫苗接种为控制 ILTV 感染提供了一种预防选择，并且可能成为替代当前活疫苗的候选者。