BSA动物免疫过程抗原抗体亲和动力学特性的研究

发布时间：2018-07-05 15:17

本文选题：抗原抗体亲和力 + 动力学　；参考：《福州大学》2005年硕士论文

【摘要】：抗体是抗原刺激人或动物机体的免疫系统后,由B 淋巴细胞系的终末分化细胞──浆细胞产生的、可与抗原特异性结合的免疫球蛋白。本课题使用牛血清白蛋白(BSA)作为抗原,通过对小鼠和白兔进行连续多次免疫和间隔长久免疫,分析抗原抗体亲和特性,探讨不同免疫周期下抗体产生及亲和力成熟的动力学变化规律。伴随免疫次数的增加,机体中抗体效价不断增强,连续出现的抗原信号使机体中的抗体始终维持在一个较高的水平。使用我们自己建立的尿素洗脱的ELISA 方法,对不同免疫周期下抗体的亲和常数进行计算,表明抗体亲和力水平在二次免疫应答时存在一个明显的突变过程。抗体亲和常数从1.6×108L/mol 上升到6.9×108L/mol。随后免疫次数虽然继续增加,但亲和力变化趋于稳定,最终稳定于7.2×108L/mol。通过比较连续刺激与间隔长久后再次刺激动物时其体内抗体亲和力变化规律,发现机体中存留的记忆细胞是那些在免疫应答过程能分泌高亲和力抗体的效应细胞的后代,其特异性亲和力始终维持在一个较高的水平。同时,机体中B 细胞表面受体BCR 虽然其本身并不发生突变,但伴随免疫次数的增加,B 细胞对抗原的亲和力也会逐渐增强,三次免疫后经过筛选后的B 细胞的BCR 与初次免疫相比,其相对亲和常数比初次免疫时提高了5倍。表明机体内对记忆性B 细胞也存在一个连续筛选的过程。应用毛细管电泳技术测定不同抗原表位之间的亲和力变化,通过计算不同免疫周期下不同表位之间的亲和常数的变化,分析免疫应答过程中优势表位的物理特性。分别比较线性表位与空间表位对抗体亲和力成熟变化的贡献,表明空间表位具有一定的竞争优势。线性表位与抗体的亲和力从初次免疫时占平均水平(整体表位)亲和力的75%降低至四次免疫后的69%。本课题的研究对于研究疫苗、抗体的作用机制提供了一定的理论依据,对以表位为基础的现代疫苗的设计具有一定的推动意义。
[Abstract]:Antibodies are immunoglobulins that specifically bind to antigens that stimulate the immune system of humans or animals and are produced by terminal differentiation cells of the B lymphocyte line, plasma cells. In this study, bovine serum albumin (BSA) was used as antigen to analyze the affinity of antigen-antibody to mice and rabbits by repeated immunization and long-interval immunization. To investigate the dynamic changes of antibody production and affinity maturation in different immune cycles. Along with the increase of immunization times, the titer of antibodies in the body is increasing, and the continuous appearance of antigen signals keeps the antibody in the body at a high level. Using the Urea elution Elisa established by ourselves, the affinity constants of antibodies in different immune cycles were calculated. The results showed that there was an obvious mutation process in the secondary immune response. The antibody affinity constant increased from 1.6 脳 10 ~ (8) L / mol to 6.9 脳 10 ~ (8) L / mol. After that, the number of immunizations continued to increase, but the change of affinity tended to be stable, and finally stabilized at 7.2 脳 10 ~ (8) L / mol. By comparing the changes of antibody affinity between continuous stimulation and repeated stimulation of animals at long intervals, it was found that the memory cells in the body were the offspring of the effector cells that secreted high affinity antibodies during the immune response. Its specific affinity is always maintained at a high level. At the same time, although the B cell surface receptor BCR itself does not mutate, the affinity of B cell to antigen increases with the increase of immune times. The BCR of B cell screened after three times of immunization is compared with that of primary immunization. Its relative affinity constant was 5 times higher than that of primary immunization. It suggests that there is also a continuous screening process for memory B cells in the body. Capillary electrophoresis (CE) was used to determine the affinities of different antigenic epitopes. The physical properties of dominant epitopes in immune response were analyzed by calculating the affinity constants of different epitopes in different immune cycles. The contributions of linear epitopes and spatial epitopes to the mature changes of antibody affinity were compared, which indicated that the spatial epitopes had certain competitive advantages. The affinity of linear epitopes to antibodies decreased from 75% of the average (global epitope) affinity at the time of primary immunization to 69% after four doses of immunization. The research in this paper provides a theoretical basis for the study of vaccine and the mechanism of antibody action, and has a certain significance for the design of modern vaccine based on epitope.
【学位授予单位】：福州大学
【学位级别】：硕士
【学位授予年份】：2005
【分类号】：R392

【引证文献】