Batista F D, Neuberger M S
Medical Research Council, Laboratory of Molecular Biology, Cambridge, United Kingdom.
Immunity. 1998 Jun;8(6):751-9. doi: 10.1016/s1074-7613(00)80580-4.
Initiation and affinity maturation of the humoral immune response is driven by antigen interaction with BCR. To study how signaling and antigen presentation through BCR depend on antigen/BCR affinity, lysozyme-specific B cell transfectants were challenged with mutated lysozymes differing in their binding kinetics. For detectable triggering, the antigen/BCR complex needed a Ka > 10(6) M(-1) (dissociation half-life > approximately 1 s). Mutated lysozymes whose binding was below this threshold could nevertheless be presented if complexed with soluble antibody. Above the threshold, the concentration of antigen required to trigger a response decreased as the affinity (particularly dissociation half-life) increased. However, a plateau was reached at Kas > approximately 10(10) M(-1) (dissociation half-life > 0.5 hr), supporting the idea of a ceiling to affinity maturation.
体液免疫反应的启动和亲和力成熟是由抗原与BCR的相互作用驱动的。为了研究通过BCR的信号传导和抗原呈递如何依赖于抗原/BCR亲和力，用结合动力学不同的突变溶菌酶对溶菌酶特异性B细胞转染子进行刺激。为了实现可检测的触发，抗原/BCR复合物需要Ka>10(6) M(-1)（解离半衰期>约1秒）。结合低于此阈值的突变溶菌酶如果与可溶性抗体复合也可以被呈递。高于阈值时，触发反应所需的抗原浓度随着亲和力（特别是解离半衰期）的增加而降低。然而，当Kas>约10(10) M(-1)（解离半衰期>0.5小时）时达到平台期，支持了亲和力成熟存在上限的观点。
