Establishment of human abzymes-generation system by using light chain shifting in human B cells

利用人B细胞轻链转移建立人抗体酶产生系统

基本信息

批准号：
15580306
负责人：
TACHIBANA Hirofumi
金额：
$ 2.3万
依托单位：
Kyushu University
依托单位国家：
日本
项目类别：
Grant-in-Aid for Scientific Research (C)
财政年份：
2003
资助国家：
日本
起止时间：
2003 至 2005
项目状态：
已结题

项目摘要

One mechanism whereby the immune system recognizes and distinguishes foreign antigens is by generating a large and diverse repertoire of antibody molecules. This diversity protects organisms from a wide range of pathogens and toxic agents and has been exploited to produce high affinity-selective receptors for use as diagnostics, molecular probes, and therapeutic agents. On the other hands, autoantibodies attack self as an antigen, which characterizes most autoimmune diseases. Although a number of possibilities have been investigated, the mechanism responsible for the production of autoantibodies remains unsolved.Antibody genes are assembled during B cell development through a series of site-specific recombination events collectively termed V(D)J recombination. Although the V(D)J recombination at the light chain loci occur in immature B cells, we have found that the original light chain is replaced with another light chain which results from secondary V(D)J recombination (light chain shifting) in some human antibody-secreting B cells. Light chain shifting can be induced upon treatment with agents with phosphatase inhibitory activity such as caffeine and okadaic acid, the agent that stimulates protein kinase C, whereas factors that increase intracellular cAMP and calcium, and inhibit serine/threonine protein kinase did not induce light chain shifting. A light chain that is resulting from the light chain shifting has a protease activity.

免疫系统识别和区分外来抗原的一种机制是产生大量多样的抗体分子。这种多样性可以保护生物体免受多种病原体和有毒物质的侵害，并已被用来生产高亲和力选择性受体，用作诊断剂、分子探针和治疗剂。另一方面，自身抗体将自身作为抗原攻击，这是大多数自身免疫性疾病的特征。尽管已经研究了多种可能性，但产生自身抗体的机制仍未解决。抗体基因在 B 细胞发育过程中通过一系列位点特异性重组事件（统称为 V(D)J 重组）进行组装。尽管轻链位点上的 V(D)J 重组发生在未成熟的 B 细胞中，但我们发现，在一些细胞中，原始轻链被由二次 V(D)J 重组（轻链移位）产生的另一条轻链取代。分泌人类抗体的 B 细胞。使用具有磷酸酶抑制活性的药物（例如咖啡因和冈田酸，刺激蛋白激酶 C 的药物）治疗后可以诱导轻链转移，而增加细胞内 cAMP 和钙以及抑制丝氨酸/苏氨酸蛋白激酶的因子不会诱导轻链转移转移。由轻链转移产生的轻链具有蛋白酶活性。