季节性流感病毒裂解疫苗在小鼠体内的免疫原性分析

Immunogenicity of seasonal influenza virus split vaccine in mice

目的分析季节性流感病毒裂解疫苗在小鼠体内的免疫原性。方法将3批季节性流感病毒裂解疫苗进行不同倍数稀释后,分别采用1针及2针免疫程序经腹腔免疫小鼠,0.5 ml/只。血凝抑制法测定小鼠血清中H1N1、H3N2和B型抗体滴度,并计算抗体几何平均值（GMT）及疫苗半数有效剂量（ED50）;H1N1亚型及H3N2亚型以≥1∶40为阳转判定标准,B型以≥1：10为阳转判定标准来判定小鼠血清抗体阳转率。结果 3批原倍疫苗H1N1、H3N2和B型阳转率均达100%,随着疫苗稀释度增加,阳转率呈阶梯状下降,ED50分别为0.27～0.46、0.28～0.76和2.08～3.89μg。3批原倍疫苗进行1针免疫程序后,小鼠血清中H1N1、H3N2和B型的GMT分别为1∶184～1∶226、1∶106～1∶184和1∶14～1∶40,随着疫苗稀释度增加,各批疫苗的抗体GMT值均呈现逐步下降趋势;3批1∕3倍疫苗进行2针免疫程序后,H1N1、H3N2和B型的GMT分别为1∶1 372～1∶1 810、1∶905～1∶1 194和1∶343～1∶368。结论 3批季节性流感病毒裂解疫苗在小鼠体内均具有良好的免疫原性,本实验为季节性疫苗免疫原性的评价提供了实验依据。

Objective To analyze the immunogenicity of seasonal influenza virus split vaccine in mice. Methods Three batches of seasonal influenza virus split vaccine were diluted, with which mice were immunized i. p. by a single dose or two-dose schedule, 0. 5 ml for each. The antibody titers against influenza virus subtypes H1N1, H3N2 and B in sera were determined by hemagglutination inhibition（HI）test, based on which the geometric mean titer（GMT）and median effective dose（ED50）were calculated. If the antibody titers against influenza virus subtypes H1N1 and H3N2 were not less than1 ∶ 40, while that against subtype B was not less than 1 ∶ 10, the results were judged as positive. Results All the positive conversion rates of antibodies against influenza virus subtypes H1N1, H3N2 and B in the mice immunized with original vaccine were 100%. The positive conversion rate decreased at a gradient with the increasing dilution of vaccine. The ED50 of vaccine of subtypes H1N1, H3N2 and B were 0. 27 ～ 0. 46, 0. 28 ～ 0. 76 and 2. 08 ～ 3. 89 μg respectively.The GMTs of antibodies against influenza virus subtypes H1N1, H3N2 and B in sera of mice were 1 ∶ 184 ～ 1 ∶ 226,1 ∶ 106 ～ 1 ∶ 184 and 1 ∶ 14 ～ 1 ∶ 40 respectively after immunization with a single dose of three batches of original vaccine, which decreased gradually with the increasing dilution of vaccine. However, the GMTs against subtypes H1N1,H3N2 and B after immunization with two dose of vaccine at a dilution of 1 ∶ 3 were 1 ∶ 1 372 ～ 1 ∶ 1 810, 1 ∶ 905 ～ 1 ∶ 1 194 and 1 ∶ 343 ～ 1 ∶ 368, respectively. Conclusion Three batches of seasonal influenza virus split vaccine showed good immunogenicity in mice, which provided an experimental basis for evaluation of immunogenicity of the vaccine.