IG GENETICS--ONTOGENY AND DIFFERENTIATION OF CELLS OF THE RABBIT IMMUNE SYSTEM

我们利用免疫遗传学和分子生物学技术， 兔免疫球蛋白和其他基因，包括RAG-1和RAG-2， 是淋巴细胞增殖过程中基因重排的必要条件 发展 我们研究了解剖部位的发展， 作为肠相关淋巴细胞中的阑尾滤泡和生殖中心， 组织与IG的调控表达和序列多样性 淋巴细胞发育过程中的基因。 而具有重排的B细胞 VH 1在正常兔中占优势，在纯合子Alicia突变兔中占优势 (ali/ali）VH 1基因缺失，具有上游VH基因的B细胞 重新安排 我们发现正常人阑尾发育的差异 免疫组化、细胞分析、免疫组织化学、免疫组化 增殖和凋亡性死亡。 附录的发展 变种人似乎比正常人反应迟钝 作为人口 携带VHa 2样表位的B细胞在突变动物中发育，附录 发展看起来更像正常。 高比例的B细胞 表达A2同种异型可能会收到强烈的信号， 而不是经历凋亡。 VHa 2阳性B细胞表达高水平的 Bcl-2蛋白与α 2阴性B细胞相比。 这表明B 具有FR同种异型基序的细胞可能对程序化细胞具有抗性， 通过Bcl-2途径死亡。 a2同种异型可能起着功能性作用， 在阑尾中B细胞的选择和有效扩增中的作用。 我们现在已经确定了CD 5作为B细胞表面免疫球蛋白的配体。 固定化F（ab '）2片段从阑尾细胞中分离CD 5分子 裂解物。我们纯化并生物素化了来自人血清的F（ab '）2片段， 正常（α 2+）和VH突变动物（α 2-），并将它们用作探针。 通过 流式细胞术显示，VHa 2 + F（ab '）2比VHa 2-F（ab'）2更强地结合IgM+ B细胞。 F（ab'）2. 这种相互作用以及F（ab '）2与阑尾的结合 抗CD 5抗体可以阻断生发中心。 细胞附着 分析还表明，B细胞表面糖蛋白CD 5是一种配体， 对于B细胞表面免疫球蛋白框架区序列。 VH框架区结构与内源性配体的相互作用 如CD 5可能影响特定细胞维持和选择性扩增， B细胞。

We used techniques of immunogenetics and molecular biology to study rabbit immunoglobulins, and other genes including RAG-1 and RAG-2, which are necessary for gene rearrangements to occur during lymphocyte development. We investigated the development of anatomical sites such as appendix follicles and germinal centers in gut-associated lymphoid tissues and the regulated expression and sequence diversification of Ig genes during lymphoid cell development. Whereas B cells with rearranged VH1 predominate in normal rabbits, in homozygous Alicia mutant rabbits (ali/ali) the VH1 gene is deleted and B cells with upstream VH genes rearrange. We found differences between appendix development in normal and ali/ali rabbits based on immunohistochemistry, analyses of cell proliferation and apoptotic death. The development of the appendix in mutants appears to be retarded compared to normals. As populations of B cells bearing VHa2-like epitopes develop in mutant animals, appendix development appears more like normals. A higher proportion of B cells expressing the a2 allotype may receive strong signals to survive rather than undergo apoptosis. VHa2-positive B cells express high levels of Bcl-2 protein compared to a2-negative B cells. This suggests that B cells with FR allotypic motifs may become resistant to programmed cell death via the Bcl-2 pathway. The a2 allotype probably plays functional role(s) in selection and effective expansion of B cells in the appendix. We have now identified CD5 as a ligand for B-cell surface immunoglobulin. Immobilized F(ab')2 fragments isolate CD5 molecules from appendix cell lysates. We purified and biotinylated F(ab')2 fragments from sera of normal (a2+) and VH mutant animals (a2-) and used them as probes. By flow cytometry, VHa2+ F(ab')2 bind IgM+ B cells more strongly than VHa2- F(ab')2. This interaction as well as F(ab')2 binding to appendix germinal centers can be blocked by anti-CD5 antibodies. Cell attachment assays also suggest that the B cell-surface glycoprotein CD5 is a ligand for B cell surface immunoglobulin framework region sequences. Interactions of VH framework region structures with endogenous ligands such as CD5 may affect maintenance and selective expansion of particular B cells.