INFLUENZA REASSORTANT VIRUS--BIOLOGY AND GENETICS

为了适合生产流感病毒疫苗和 为了在疫苗接受者中诱导保护性免疫反应，一位候选人 种子病毒必须含有血凝素和神经氨酸酶表面糖蛋白 与在人类中传播的主要野生型病毒相匹配 人口。然而，许多野生型流感病毒株是 复制能力相对较差；如果用于疫苗生产，可能 减少流感季节前可生产的疫苗总量或 推迟商业用途疫苗的供应。这是可能的 重新配对流感病毒，以便后代病毒包含这两种病毒 野生型供体病毒的血凝素和神经氨酸酶基因 内部的6个基因来自另一个高产量的供体 特点。已经开始了生产高产的研究 用于疫苗生产的重组病毒，目的是使用 相同的病毒，以更好地了解重要的基因组特征 在控制鸡蛋中的病毒复制方面。在启动的过去一年中- 在研究上，重点一直放在开发1)优化 供体病毒在卵子内和在卵子中重新配型的混合感染率 组织培养；2)雪貂和绵羊抗血清的制备和检测 抑制高产供体病毒所需的条件及其筛选 高产量重组剂；3)开发限制稀释策略 用于分离鸡蛋中所需重组子的克隆；以及4) 重组子代的表型和基因鉴定 方法包括在血清学检测中的抗原性，鉴定 用聚丙烯酰胺凝胶电泳法测定基因组RNA大小并扩增 通过聚合酶链式反应获得独特的基因序列。

In order to be suitable for the production of influenza virus vaccines and to induce a protective immune response in vaccine recipients, a candidate seed virus must have hemagglutinin and neuraminidase surface glycoproteins that match the predominant wild type virus circulating in the human population. However, many wild type strains of influenza viruses are relatively poor at replication; and, if used for vaccine production, may reduce the total amount of vaccine producible before influenza season or delay the availability of vaccine for commercial use. It is possible to reassort influenza viruses so that the progeny virus contains the two genes for the hemagglutinin and neuraminidase from a wild type donor virus and the internal six genes from another donor with high yield characteristics. Studies have been started to produce high yield reassortant viruses for vaccine production with the intent of using the same viruses to better understand the genomic features which are important in controlling virus replication in eggs. During the past year of start- up studies, emphasis has been place on developing 1) optimization of the coinfection ratio of the donor viruses for reassortment in eggs and in tissue cultures; 2) production and testing of ferret and sheep antisera needed for suppresssion of the high yield donor virus and selection of the high yield reassortants; 3) development of a limiting dilution strategy for the isolation of clones of desired reassortants in eggs; and 4) identification of the phenotype and genotype of the reassorting progeny by methods including antigenicity in serologic assays, identification of genome by RNA sizing in polyacrylamide electrophoresis, and amplification of unique gene sequences by polymerase chain reaction.