CHILDRENS ANTIBODIES TO POLYSACCHARIDES--V REGION GENES

B细胞抗体库的显著多样性产生了 通过不同免疫球蛋白组的组合分类 (IG)生殖系成分。重排免疫球蛋白基因的进一步多样化 是由独特的体细胞超突变过程提供的。个人 这些机制中的每一个对功能抗体的贡献 曲目不详。对囊膜的抗体反应 儿童主要致病菌嗜血杆菌的多糖(PS) B型流感病毒(Hib)，仅限于有限数量的抗体。 种(CL诺型)。因此，它应该成为一个很好的榜样 检验不同种系变量的相对贡献率(V) 区域和体细胞突变对功能性免疫反应的影响。 此外，对这种感染的易感性是年龄和 可能与V基因使用的个体发育有关。这个项目的总体目标是 建议研究人类V区基因谱系的表达 作为年龄和抗原暴露形式的函数。在这项研究中 我们建议1)以人抗Hib PS B细胞的形式分离 婴儿、儿童和成人不同时期的杂交瘤 T非依赖(TI)和T依赖(TD)形式的Hib PS免疫 疫苗，2)通过序列分析确定免疫球蛋白区域谱系 杂交瘤基因克隆的筛选及血清抗独特型分析 抗体与外周血B细胞的关系，3)考察 V区序列或Ig亚型与抗Hib PS的功能活性 抗体，以及4)检测Ig基因体细胞的贡献 TD和TI对免疫球蛋白区域多样性的高度突变 疫苗。B细胞杂交瘤抗体的V基因可以很容易地 已排序。此外，V区的发展具有特异性 抗独特型抗体将允许分析大量的 无需分离、克隆和测序大量的血清样本 杂交瘤的数量。不同时间捕获的V基因的比较 免疫后的时间点将决定V的贡献 基因的使用和体细胞突变对抗体反应的成熟。 确定体细胞突变对TI和TD反应的影响 将阐明T细胞在这一独特过程中的作用。最后， 不同年龄段的V区使用情况将决定个体发育 V基因的使用情况，并可能为某些疾病的易感性提供线索 患者对这种感染的反应。

The remarkable diversity of the B cell antibody repertoire is generated through the combinatorial assortment of distinct groups of immunoglobulin (Ig) germline elements. Further diversification of rearranged Ig genes is provided by a unique process of somatic hypermutation. The individual contribution of each of these mechanisms to the functional antibody repertoire is unknown. The antibody response to the capsular polysaccharide (PS) of a major childhood bacterial pathogen, Haemophilus influenzae type b (Hib), is restricted to a limited number of antibody species (cl notypes). Therefore it should serve as an excellent model to examine the relative contribution of different germline variable (V) regions and somatic mutation to the functional immune response. Furthermore, susceptibility to this infection is a function of age and may be related to the ontogeny of V gene usage. The overall goal of this proposal is to study the expression of the human V region gene repertoire as a function of age and the form of antigenic exposure. In this study we propose 1) To isolate human antiHib PS B cells in the form of hybridomas from infants, children and adults at various times following immunization with T-independent (TI) and T-dependent (TD) forms of Hib PS vaccine, 2) To determine the IgV region repertoire by sequence analysis of cDNA clones of hybridomas and by anti-idiotype analysis of serum antibodies and peripheral B cells, 3) To examine the relationship between V region sequence or Ig isotype, and functional activity of anti-Hib PS antibodies, and 4) To examine the contribution of Ig gene somatic hypermutation to IgV region diversity in response to both TD and TI vaccines. The V genes of the B cell hybridoma antibodies can be readily sequenced. In addition, the development of V region specific anti-idiotype antibodies will allow the analysis of a large number of serum samples without the need to isolate, clone and sequence a large number of hybridomas. Comparison of V genes captured at different timepoints following immunization will determine the contribution of V gene usage and somatic mutation to maturation of the antibody response. Determining the impact of somatic mutation in both TI and TD responses will clarify the role of T cells in this unique process. Finally, knowledge of V region usage at different ages will determine the ontogeny of V gene usage and may provide clues to the susceptibility of certain patients to this infection.