单克隆抗体对小苍兰褪绿条纹花叶病毒及其决定簇的作用特性

Monoclonal Antibodies to Freesia Chlorotic Stripe Mosaic Virus and Their Characteristics of Binding to Antigenic Determinants on the Coat Protein

采用杂交瘤技术，得到抗小苍兰褪绿色条纹花叶病毒（FCSMV）六个单克隆抗体P3、4A4，6B、，7A6，7D1和7DS。ELISA效价分别为1：1062－1：10^6。7A6攻7D1属于IgG1亚类，7D8和4A4分属IgG2a和IgG2b亚类，P3和6B1属于IgG2亚类。电镜观察单克隆抗体与病毒形成的复合物发现7D1能使病毒粒子发生严重裂断。6株单克隆抗体中P3，4A4、6B1对应于病毒外壳蛋白上的顺序决定簇。纯化的病毒外壳蛋白经酶裂解和改进的盘状电泳分离，得到八段与多克隆抗体反应的收集液。用顺序决定族的单克隆抗体检出P3对应的肽段22和4A4对应的肽段78。本文还讨论了7D1使病毒粒子发生断裂的原因和与病毒粒子表面结构的关系以及分离抗原决定族所在片段的意义。

Using hybridoma techniques, six monoclonal antibodies (mAb), P3, 4A4 6B1, 7A6, 7D1 and 7D8 to Freesia chlorotic stripe mosaic virus ( FCSMV), were prepared. The titers of mAb were 1:10~2—1:10~6. MAb 7A6 and 7D1 were IgG1 subclass. 7D8 and 4A4 were IgG2a and lgG2b subclass, respectively, mAb P3 and 6B1 were of IgG3 subclass. The reactions of mAb to virus particles and denatural coat protein indicated that mAb P3, 4A4 and 6B1 were associated with different sequential epitopes of coat protein, and others were associated with different structural epitopes on virus particles. MAb P3 reacted with epitope on No.22 peptide fraction and mAb 4A4 reacted with epitope on No.78 peptide fraction when each fraction which was separated by modified disc electrophoresis after degestion of coat protein by pepsin was detected by mAbs p3. 4A4 and 6B1. Only one band of No.22 or No.78 peptide fraction was shown by DNS-C1 labling, SDS-PAGE. It was found that the virus particles were broken severely when virus preparation was mixed only with mAb 7D1 but not with other mAbs and even polyclonal antibody. It is posssible that the virus structure was changed when the structural epitope binded with relative mAb 7D1 or the mAb 7D1 may have function of Abzyme.More evidences are required.