Oncogenicity of fish herpesvirus and protective immune mechanisms of fish

对鲑鱼疱疹病毒H-83株、鲑鱼疱疹病毒(OMV)株和鲑鱼疱疹病毒H-83株的生物学、血清学和遗传学关系进行了研究。感染OMV的Coho鲑鱼苗可在口腔内及周围发生肿瘤。病毒再分离结果表明，肝脏是OMV感染的靶器官；交叉酶联免疫吸附试验和交叉中和试验表明，H-83株和OMV株在血清学上相似，但与沙门氏菌不同；DNA-DNA杂交试验还表明，H-83株与OMV DNA之间存在着比它们与沙门氏菌更多的同源DNA序列。H-83株DNA的限制性内切酶酶切图谱与OMV相似，但与沙门氏菌不同。病毒体外传代33次以上后，部分片段出现或消失，而鲑鱼DNA片段在传代过程中未发生变化。前两种病毒在鱼苗传代后的毒力均有所下降。

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.