型间嵌合性脊髓灰质炎病毒的组建及抗原性分析

CONSTRUCTION AND IMMUNOGENICITY OF INTERTYPIC ANTIGENIC CHIMERAS OF POLIOVIRUSES

以脊髓灰质炎病毒1型Mahoney株全基因cDNA为载体,将人工合成的2型Laosing株与3型Leon株的中和抗原位点Ⅰ(N-AgⅠ)的cDNA片段,插入Mahoney株N-AgⅠ的相应部位,构成1/2型与1/3型嵌合基因,经体外转染与病毒纯化,得到4株型间嵌合病毒。血清学试验表明,此嵌合病毒呈现多价抗原反应性;嵌合病毒可同时或分别被2个母型毒株的抗血清中和;免疫家兔后能产生2个型的中和抗体。

Recently, intertypic chimeras of polioviruses have been obtained abroad by means of genetic engineering. Using the whole genomic cDNA vector of Mahoney strain (Type 1 ),we used synthesized cDNA sequences encoding neutralizing antigenic site l ( N-Ag I ) of Lansing strian (Type 2 ) and Leon strain ( Type 3 ) to replace the corresponing regions of Mahoney genomic vectors. In this way, four hybrid genomes of type 1/2 or type 1/3 of poliovirus were abtained. After transfection of the genomes and purification of viruses, four antigenic chimeras of polio virus strains were obtained.Further studies of the neutralizing immunogenicity of the four chimerical viruses showed that they can be neutralized by antibodies to, and can induce production of neutralizing antibodies in rabbits against, their parental viruses.