Ono S, Takahama Y, Hamaoka T
Department of Oncogenesis, Osaka University Medical School, Japan.
J Immunol. 1987 Nov 15;139(10):3213-23.
We have demonstrated that B cell recognition of Ia molecules is involved in polyclonal B cell differentiation by B151-TRF2. The present study was undertaken to examine the Ia recognition specificity of B151-TRF2-responsive B cells in fully major histocompatibility complex (MHC)-allogeneic P1----P2, semiallogeneic P1----(P1 x P2)F1, and double donor (P1 + P2)----(P1 x P2)F1 and (P1 + P2)----P1 radiation bone marrow chimeras. The B cells from both P1----P2 and P1----(P1 x P2)F1 chimeras could give rise to in vitro immunoglobulin M-producing cells upon stimulation with B151-TRF2 comparable in magnitude to that of normal P1 B cells, and their responses were inhibited by anti-I-AP1 but not by anti-I-AP2 monoclonal antibody even in the presence of mitomycin C-treated T cell-depleted P2 spleen cells as auxiliary cells. In contrast, the B151-TRF2 responses of P1 B cells isolated from both (P1 + P2)----(P1 x P2)F1 and (P1 + P2)----P1 double bone marrow chimeras became sensitive to the inhibition of not only anti-I-AP1 but also anti-I-AP2 monoclonal antibody only when the culture was conducted in the presence of P2 auxiliary cells, demonstrating that they adaptively differentiate to recognize as self-structures allogeneic as well as syngeneic Ia molecules. Moreover, the experiments utilizing B cells from H-2-congenic mice and B cell hybridoma clones as auxiliary cells revealed that B151-TRF2-responsive B cells recognize Ia molecules expressed on B cells. Taken together, these results demonstrate that B151-TRF2-responsive B cells recognize Ia molecules expressed by B cells as self-structures and that their self-recognition specificity is dictated by the MHC haplotype of bone marrow cells present during the B cell ontogeny but not by the MHC haplotype of a radiation-resistant host environment.
我们已经证明，B151 - TRF2介导的多克隆B细胞分化涉及B细胞对Ia分子的识别。本研究旨在检测在完全主要组织相容性复合体（MHC）同种异体P1----P2、半同种异体P1----(P1×P2)F1以及双供体(P1 + P2)----(P1×P2)F1和(P1 + P2)----P1辐射骨髓嵌合体中，对B151 - TRF2有反应的B细胞的Ia识别特异性。来自P1----P2和P1----(P1×P2)F1嵌合体的B细胞在用B151 - TRF2刺激后，能在体外产生免疫球蛋白M产生细胞，其数量与正常P1 B细胞相当，并且即使在存在经丝裂霉素C处理的T细胞耗竭的P2脾细胞作为辅助细胞的情况下，它们的反应也受到抗I - AP1单克隆抗体的抑制，而不受抗I - AP2单克隆抗体的抑制。相反，从(P1 + P2)----(P1×P2)F1和(P1 + P2)----P1双骨髓嵌合体中分离出的P1 B细胞，只有在有P2辅助细胞存在的情况下进行培养时，其对B151 - TRF2的反应才不仅对抗I - AP1单克隆抗体的抑制敏感，而且对抗I - AP2单克隆抗体的抑制也敏感，这表明它们适应性分化以将同种异体以及同基因的Ia分子识别为自身结构。此外，利用来自H - 2同基因小鼠的B细胞和B细胞杂交瘤克隆作为辅助细胞的实验表明，对B151 - TRF2有反应的B细胞识别B细胞上表达的Ia分子。综上所述，这些结果表明，对B151 - TRF2有反应的B细胞将B细胞表达的Ia分子识别为自身结构，并且它们的自身识别特异性由B细胞个体发育过程中存在的骨髓细胞的MHC单倍型决定，而不是由抗辐射宿主环境的MHC单倍型决定。
