Adaptire differentiation of self-Ia-recognition molecules involved in B-B cell interaction

通过本研究，得出以下结论：1.通过识别H-2复合物内的自身I区产物（Ia分子）的B-B细胞相互作用过程参与了由T细胞衍生的B细胞分化因子B151-TRF 2或脂多糖（LPS）诱导的多克隆B细胞分化. B细胞对自身Ia分子的识别是由除表面免疫球蛋白和LFA-1分子以外的尚未确定的分子介导的，所述表面免疫球蛋白和LFA-1分子被报道在免疫系统中起粘附分子的作用。H-2-杂合F1 B细胞显示由至少两个分离的群体组成，其仅识别亲本Ia分子之一。B细胞的Ia识别特异性是“可塑性的”，并由B细胞个体发育过程中存在的辐射敏感骨髓细胞的H-2单倍型决定，而不是由能够决定施加于T细胞上的自身Ia限制特异性的辐射抗性宿主元件决定.发现B细胞表达I-A产物的自我识别受体，但不表达I-E产物.通过利用X-连锁免疫缺陷CBA/N小鼠的B细胞中自身I-A ^k识别分子表达的功能缺陷，通过将P3 U1骨髓瘤细胞与来自缺陷型小鼠的脾细胞融合，建立了能够抑制I-A κ限制性B-B细胞相互作用的单克隆抗体3A 8 -3。用正常（CBA/N x B10.BR）F1雌性脾细胞免疫的（CBA/N x B10.BR）F1（H-2^k）雄性小鼠。

By this study, the following conclusions were obtained:1. B-B cell interaction process via recognition of self-I-region products (Ia molecules) within H-2 complex was involved in a polyclonal B cell differentiation induced by a T cell-derived B cell differentiation factor B151-TRF2 or lipopolysaccharide (LPS).2. The recognition by B cells of self-Ia molecules was mediated by as yet undefined molecules other than the surface immunoglobulin and LFA-1 molecules which are reported to function as adhesion molecules in immune system.3. H-2-heterozygous Fl B cells were shown to consist of at least two separate populations which recongnize only one of the parental Ia molecules.4. The Ia-recognition specificity of B cells was "plastic" and determined by the H-2 haplotype of radiation-sensitive bone marrow cells present during B cell ontogeny but not by that of radiation-resistant host elements capable of dictating self-Ia restriction specificity imposed on T cells.5. B cells were found to express self-recognition receptor for I-A products but not for I-E products.6. By taking advantage of functional defect(s) in the expression of self-I-A^k recognition molecules in B cells of X-linked immunodeficient CBA/N mice, monoclonal antibody 3A8-3 capable of inhibiting I-A^k-restricted B-B cell interaction was established by fusion of P3U1 myeloma cells with spleen cells from defective (CBA/N x B10.BR)F1(H-2^k) male mice which was immunized with normal (CBA/N x B10.BR)F1 female spleen cells.