Studies on the T-cell epitopes of herpesviruses

在抗糖蛋白B（gB）单克隆抗体的存在下，获得了一株牛疱疹病毒1型（BHV 1）逃逸突变株。该突变株对其它3种抗gB单克隆抗体也具有抗性，这些抗体具有补体非依赖性中和活性。目前正在分析突变体gB的氨基酸取代。BHV 1感染牛的外周血淋巴细胞的细胞毒活性也正在研究中，使用的MUSCLAND感染的原代培养物作为一个目标，以研究氨基酸取代是否影响T细胞的recognition.To开发更有效和更安全的疫苗对牛传染性鼻气管炎，亚单位疫苗含有杆状病毒表达的BHV 1的gC和/或gD进行鼻内免疫牛。在疫苗中加入霍乱毒素B亚单位作为佐剂。经鼻内免疫的牛，其鼻分泌物中产生抗BHV 1的中和抗体，用105.0PFU的BHV 1攻击后，病毒很少脱落。用107.8PFU的ADV攻击牛，牛的临床症状减轻，病毒脱落减少，小鼠鼻内注射表达ADV gD的质粒，在气管-肺洗液中产生抗ADV的抗体，并能抵抗致死剂量的ADV鼻内攻击。经鼻内注射gC表达质粒的小鼠也能抵抗病毒攻击。由于在小鼠鼻分泌物、气管-肺洗液和血清中均未检测到抗体，因此呼吸道粘膜细胞表达的gC可能诱导细胞免疫以抵抗攻击。

An escape mutant of bovine herpesvirus 1 (BHV1) was obtained in the presence of monoclonal antibody against glycoprotein B (gB) , which required complement for virus neutralization. The mutant was also resistant to other 3 monoclonal antibodies against gB,which exhibited complement-independent neutralizing activity. Amino acid substitution of gB of the mutant is now being analyzed. The cytotoxic activity of peripheral blood lymphocytes from BHV1-infected cattle is also being investigated using the mutant-infected primary culture as a target to study whether the amino acid substitution affects recognition by T cells.To develope more effective and safer vaccine against infectious bovine rhinotracheitis, intranasal immunization of cattle with subunit vaccines containing baculovirus-expressed gC and/or gD of BHV1 was performed. Cholera toxin B subunit was added to the vaccines as amucosal adjuvant. Cattle immunized intranasally with the vaccines produced neutralizing antibodies against BHV1 in the nasal secresions and scarecely shed the virus after challenge with 105.0PFU of BHV1. When cattle were challenged with 107.8PFU of the virus, they showed less severity of clinical signs and less virus shedding.Mice intranasally administrated with plasmid expressing gD of Aujeszky's disease virus (ADV) produced antibodies against the virus in the trachea-lung washes and resisted to intranasal challenge with a lethal dose of the virus. Mice intranasally administrated with gC-expressing plasmid also resisted to the virus challenge. Since no antiody was detected in the nasal secresions, trachea-lung washes or serum of the mice, gC expressed in the respiratory mucosal cells may induce cellular immunity to protect from the challenge.