B淋巴细胞对兔免疫球蛋白和兔抗鼠IgM抗体的提呈作用

Presentation of Rabbit Anti-Mouse IgM Antibody and Rabbit Immunogolobulin by B Lymphocytes

本文采用兔免疫蛋白特异的鼠T细胞株为靶细胞,以T细胞的增殖和IL-2的产生活性为反应指标,探讨了小鼠B淋巴细胞兔免疫球蛋白和兔抗鼠IgM等抗原的提呈作用。实验结果显示,B细胞对兔抗鼠IgM抗体有很强的提呈作用,提呈兔抗鼠IgM抗体所需的抗原浓度较低,比兔免疫球蛋白低1000倍以上,当用巨噬细胞作为抗原提呈细胞时,则无上述差异。故提示可用兔抗鼠IgM抗体模拟抗原特异性B细胞的高效抗原提呈作用。此研究结果为进一步探讨抗原特异性B细胞抗原提呈作用的特点,以及T—B细胞间相互作用的途径和机制,提供了有用的实验模型。

By two independent assays(T cell proliferation and interleukin-2 secretion),presentations of rabbit anti-mouse IgM antibody(RAMIgM) and rabbit immunoglo-bulin(RIg) by B lymphocytes and macrophages were investigated with Rig-specific T cell line. The results showed that RAMIgM was presented at concentrations 108-fold lower than Rig in T cell proliferation when B lymphocytes were used as antigen presenting cells,and similar results were obtained in interleukin-2 secretion of T cell line (see Fig. 1 and Fig. 2). But,if antigen presenting cells were macrophages,RAMIgM was presented at the similar concentrations to RIg. These results suggested,(1) the efficiency of antigen presentation is dependent primarily on the avidity of binding of a ligand to B cell surface Ig;(2) high efficiency presentation of B lymphocytes can be mimicked by anti-IgM antibody; and(3) anti-IgM antibodies are valid models for pursuing characteristics of presentation by antigen-specific B lymphocytes and cognate interactions between antigen-specific B and T lymphocytes.