摘要
麻疹病毒仅 1个血清型 ,但通过对流行株的血凝 (H)蛋白和核 (N)蛋白基因的序列分析 ,至 2 0 0 1年 10月世界卫生组织根据有关资料确认麻疹病毒有 8个基因组 (A、B、C、D、E、F、G、H) ,共 2 0个基因型。其间H蛋白基因和N蛋白基因的核苷酸差异达 7% ,而N基因COOH端的 4 5 0个核苷酸的差异在不同型之间 >12 %。中国流行的麻疹病毒主要为H基因组的H1型 ,是一种新的基因型。目前国内外使用的麻疹疫苗皆为A基因型 ,通过交叉中和试验证实 ,现行的麻疹疫苗免疫后的抗体能中和不同基因型的麻疹病毒流行株 ,但中和抗体滴度略低 ,仍可预防麻疹发生。
Although measles is serologically a monotypic virus,sequence analysis of the haemagglutinin(H)and nucleoprotein(N)genes has shown some differences.Until Oct.2001,based on currently available published information by WHO,there are 8 clades of genetic group designated A,B,C,D,E,F,G,H.Within these 8 clades,there are 20 genotypes.Of the 8 clade genes comprising the viral genome,the H and N genes are the most variable about 7% nucleotide variability.The most variable part of the measles genome is the 450 nucleotides that code for the COOH-terminus of the N protein.Nucleotide variability in this region can reach 12% among different genotypes.The sequence of epidemic strains in China revealed a new clade of virus,the clade H,belonging to H1 genotype.In the world,all of the measles vaccine strains widely used are genotype A.Cross-neutralization test indicated that the vaccine viruses and representative wild type viruses could neutralize the epidemic measles virus strains of different genotypes but the neutralizing titer was lower.These results showed that current vaccine-induced antibody still can prevent measles.
出处
《中国计划免疫》
2003年第1期47-52,共6页
Chinese Journal of Vaccines and Immunization
