Oncogenicity of fish herpesvirus and protective immune mechanisms of fish

对3种鲑科疱疹病毒（H-83株、虹鳟病毒（Oncorhynchus masou virus，OMV）和鲑疱疹病毒（Herpesvirus salmonis））的生物学、血清学和遗传学关系进行了研究。OMV感染的银鲑鱼苗产生了低滴度的病毒中和抗体，并出现了二次免疫反应，在口腔及周围产生了肿瘤。交叉酶联免疫吸附试验和交叉中和试验结果表明，H-83株与OMV血清学特征相似，但与H.salmonis不同，DNA-DNA杂交结果表明，H-83株与OMV的同源性高于H-83株与OMV的同源性。H-83株DNA的限制性内切酶酶切图谱与OMV相似，而与H. salmonis不同。鲑鱼病毒在体外传代33次以上后，部分片段出现或消失，但无H.鲑鱼在传代过程中发生了变化前两种病毒在鱼苗中传代后毒力下降。

Biological, serological and genetical relationships of three salmonid herpesviruses (strain H-83, Oncorhynchus masou virus (OMV) and Herpesvirus salmonis) were investigated.The strain H-83 was pathogenic to masu salmon and rainbow trout fry, however, yearing fish were not sensitive. The fish produced virus-neutralizing antibody with low titers, and the expression of secondary immune response was observed.Coho salmon fry infected with OMV developed tumors in and around the oral cavity. The results of virus re-isolation indicated that the liver was the target organ of OMV infection.Cross enzyme-linked immunosorbent assay and cross neutralization test revealed that strain H-83 and OMV were serologically similar but different from H.salmonis.DNA-DNA hybridization test also suggested the presence of many more homologous DNA sequences between strain H-83 and OMV DNAs than between them and H. salmonis.Restriction endonuclease cleavage pattern of strain H-83 DNA was similar to that of OMV but distinct from that of H. salmonis. After passages of the viruses for more than 33 times in vitro, some fragments appeared or disappeared, however, no DNA fragment of H. salmonis changed during the passages. The former two viruses showed a decrease in virulence in fry after passages.