Golubev D B, Galitarov S S, Poliakov Iu M, Litvinova O M, Bannikov A I
Zh Mikrobiol Epidemiol Immunobiol. 1984 Nov(11):50-6.
As indicated by the results of the hemagglutination inhibition (HAI) test, influenza viruses A/Leningrad/80 contain hemagglutinin (HA), similar to that of virus A/Singapore/1/57 (H2N2). Neuraminidase contained in viruses A/Leningrad/80 belongs to serological subtype N2 and is similar to that of virus A/Singapore/1/57 (H2N2). No differences in the polypeptide composition of the virus-induced proteins of viruses A/Leningrad/527/80, A/Leningrad/549/80, A/Leningrad/553/80 and virus A/Singapore/1/57 used as reference have been detected in the study of their electrophoretic mobility in polyacrylamide gel, as well as the mobility of duplexes obtained by the hybridization of the virion and complement RNA of viruses A/Leningrad/553/80 and A/Singapore/1/57. The results of the HAI test with antisera to purified HA indicate that virus A/Leningrad/549/80 contains HA similar to that of viruses A(H2N2) isolated in 1957, but not in 1964. The HAI test with the sera of polecats having the infection permits the differentiation of viruses A/Leningrad/80 from epidemic viruses A(H2N2) isolated in 1957-1965, including reference virus A/Singapore/1/57. In relation to the latter, the isolates of 1980 are older antigenic mutants. The isolates of 1980 are distinguished from virus A(H2N2), isolated in 1975 from the system of persisting influenza infection in a tissue culture, by mutation in NS-gene and the properties of RNA-polymerase. The authenticity of the isolation of viruses A(H2N2) in Leningrad in 1980 has been proved.
血凝抑制（HAI）试验结果表明，甲型列宁格勒/80流感病毒含有血凝素（HA），与甲型新加坡/1/57（H2N2）病毒的血凝素相似。甲型列宁格勒/80病毒所含的神经氨酸酶属于血清学N2亚型，与甲型新加坡/1/57（H2N2）病毒的神经氨酸酶相似。在研究甲型列宁格勒/527/80、甲型列宁格勒/549/80、甲型列宁格勒/553/80病毒以及作为对照的甲型新加坡/1/57病毒诱导蛋白在聚丙烯酰胺凝胶中的电泳迁移率，以及甲型列宁格勒/553/80和甲型新加坡/1/57病毒粒子与互补RNA杂交所得双链体的迁移率时，未检测到差异。用针对纯化HA的抗血清进行HAI试验的结果表明，甲型列宁格勒/549/80病毒含有与1957年而非1964年分离的甲型（H2N2）病毒相似的HA。用感染的白鼬血清进行HAI试验可区分1980年的甲型列宁格勒/80病毒与1957 - 1965年分离的流行甲型（H2N2）病毒，包括对照病毒甲型新加坡/1/57。相对于后者，1980年的分离株是较古老的抗原突变体。1980年的分离株与1975年从组织培养中持续流感感染系统分离的甲型（H2N2）病毒的区别在于NS基因的突变和RNA聚合酶的特性。已证实1980年在列宁格勒分离出甲型（H2N2）病毒的真实性。
