MECHANISMS OF AUTOANITBODY FORMATION IN HUMAN AGING

描述(改编自申请人的摘要)：增加 许多研究证明，老年人体内循环中的自身抗体 B细胞和T细胞功能的几个变化之一，可能发出免疫信号 衰老。这种衰老，反过来可能是导致易感性增加的原因。 老年人易患传染病和恶性肿瘤。拟议的研究 目的是测试可能导致自身抗体的可能机制 老化中的形成，区别于：i)继续或增加 V区基因片段编码的天然自身抗体的制备 很少或没有突变，以及II)产生具有突变V的自身抗体 区域片段，抗原选择抗体和/或 随机突变的累积。 健康志愿者将接受筛查，以确定三组受试者： 一)老年人(65岁以上)至少有一组自身抗体 自身抗原；二)没有自身抗体的老年人；以及三)年轻人 没有自身抗体。计划是测试同种类型，交叉反应， 和阳性血清中自身抗体的相对亲和力 一种重复性独特型的表达。比较三组受试者， 调查人员将： I)分析EBV转化的B细胞，以确定 产生自身抗体的转化细胞及其亚型和cDNA 自身反应免疫球蛋白H和L V链的序列分析 非自身反应克隆。 Ii)从外周血B细胞中提取V区cDNA文库 确定使用频率：VH系列、VK系列或个人 在天然自身抗体和正常中显著的V基因片段 年轻人的曲目。他们将随机对V区进行排序 选择克隆和具有反复出现的VH和VK段的克隆以确定 FR和CDR基因突变的频率、分布和编码效应 序列。 III)分析重排的H链和K链V区DNA文库 从外周血中提取B细胞，方法与cDNA库相同 第二次测试曲目和突变的频率、位置和性质， 包括那些处于非生产性重组中的公司。

DESCRIPTION (Adapted from the Applicant's Abstract): An increase in circulating autoantibodies in aging humans, documented in many studies, is one of several changes in B cell and T cell function that may signal immune senescence. This senescence, in turn, may underlie increased susceptibility to infectious disease and malignancy in the aged. The proposed research aims to test possible mechanisms that may contribute to autoantibody formation in aging, distinguishing between: i) continued or increased production of natural autoantibodies encoded by V region gene segments with few or no mutations and ii) production of autoantibodies with mutated V region segments, characteristic of antigen-selected antibodies and/or accumulation of random mutations. Healthy volunteers will be screened to identify three groups of subjects: i) elderly (over 65 years) with autoantibodies to at least one of a panel of autoantigens; ii) elderly without the autoantibodies; and iii) young adults without the autoantibodies. Plans are to test isotypes, cross-reactivity, and relative affinities of autoantibodies in the positive sera and expression of a recurrent idiotype. Comparing the three subject groups, the investigators will: i) analyze EBV-transformed B cells to determine the fraction of transformed cells producing autoantibodies, their isotypes, and cDNA sequences for H and L chain V regions of Ig from autoreactive and non-autoreactive clones. ii) probe V region cDNA libraries from peripheral blood B cells to determine the frequency of use of: VH families, VK families, or individual V gene segments that are prominent in the natural autoantibody and normal repertoire of young persons. They will sequence the V regions of randomly chosen clones and clones with recurrent VH and VK segments to determine the frequency, distribution and coding effects of mutations in FR and CDR sequences. iii) analyze libraries of rearranged H chain and K chain V region DNA from peripheral blood B cells in the same way as the cDNA libraries as a second test of repertoire and the frequency, site and nature of mutations, including those in nonproductive rearrangements.