论文部分内容阅读
目的鉴定我国狂犬病流行毒株JX08-45适应细胞培养后(命名为JX08-45CC株)的生物学特性。方法通过全基因组序列分析比对、小鼠脑内和外周攻毒试验和免疫原性试验,分别对JX08-45CC株的基因组特点、毒力和免疫原性进行鉴定。结果 JX08-45CC株的基因组序列与JX08-45株比对,共出现16个核苷酸突变点和7个氨基酸突变点,其中6个氨基酸变异发生在G蛋白(333位精氨酸未改变)编码区,L蛋白仅有1个氨基酸突变;在G蛋白氨基酸变异中,4个突变序列在其他细胞适应毒株CVS-11、CTN-1、Nishigahara、SAG2、Flury-LEP和SRV9中也普遍存在。JX08-45CC株培养滴度≥107TCID50/ml时,脑内接种小鼠的致死率为100%,滴度为102～106TCID50/ml时,脑内接种小鼠的致死率为20%～80%;滴度为105～108TCID50/ml时,外周肌肉接种小鼠,致死率为10%～70%;脑内和外周攻毒小鼠的潜伏期均为7～9 d,并于发病后24～48 h死亡。JX08-45CC株与狂犬病病毒CVS-11、ERA、SRV9和Flury-LEP株的中和抗体滴度差异均无统计学意义(P>0.05)。结论已对JX08-45CC株的基因组序列、毒力和免疫原性等生物学特性进行了鉴定,为开发具有我国自主知识产权的兽用狂犬病灭活疫苗候选株奠定了基础。
Objective To identify the biological characteristics of the rabies epidemic strain JX08-45 in China after its adaptation to cell culture (named JX08-45CC strain). Methods The genomic characteristics, virulence and immunogenicity of JX08-45CC strain were identified through genome-wide sequence analysis and comparison of the brain and peripheral brain and immunogenicity test. Results The genome sequence of JX08-45CC was aligned with that of JX08-45. A total of 16 nucleotide mutations and 7 amino acid mutations were found. Among them, 6 amino acid mutations occurred in the G protein (333 amino acids were unchanged) There were only 1 amino acid mutation in the coding region and L protein. Among G protein amino acid mutations, 4 mutant sequences were also common in other cell-adapted strains CVS-11, CTN-1, Nishigahara, SAG2, Flury-LEP and SRV9 . JX08-45CC strains cultured inoculated with titers ≥107TCID50 / ml, the inoculation of mice intracerebral fatality rate was 100%, the titer of 102 ~ 106TCID50 / ml, intracerebral inoculation mice mortality was 20% to 80%; Titers ranged from 105 to 108 TCID50 / ml. The mice inoculated with peripheral muscle had a lethal rate of 10% -70%. The incubation period in both intracerebral and peripheral challenge mice ranged from 7 to 9 days and ranged from 24 to 48 h death. There was no significant difference in neutralizing antibody titers between JX08-45CC strain and rabies virus CVS-11, ERA, SRV9 and Flury-LEP strains (P> 0.05). Conclusion The biological characteristics of genomic sequence, virulence and immunogenicity of JX08-45CC strain have been identified and laid the foundation for the development of candidate strains of rabies inactivated vaccine with independent intellectual property rights in China.