Class Switch Recombination in B Lymphocytes

拟议的研究继续关注调节高亲和力的发展的机制， 抗体反应，这对疫苗开发至关重要。其中有几个关键方面 完全是B细胞特异性的反应。首先，发生在特殊显微解剖结构中的克隆扩张， 称为生发中心（GC）。第二，通过体细胞突变（SHM）使抗体基因多样化 和类别转换重组（CSR），这两种重组都是由激活诱导的胞苷脱氨酶启动的 （AID）。尽管AID偏好抗体基因，但它并不完全是Ig特异性的，并且脱靶活性是主要的。 导致人类B细胞癌。高亲和力抗体开发的第三个B细胞特异性方面是 选择表达高亲和力受体的B细胞克隆。在融资期的前4年， 作为最初目标1和2的一部分，我们研究了AID靶向lg基因和错误靶向的机制。 癌基因在生殖中心。此外，我们记录了B的细胞和细胞生物学调节 生发中心细胞克隆性扩增。我们已经开始研究目标3，并取得了重大进展。 通过研究Rif-1的相互作用伙伴ZYMD 8，了解Rif-1如何介导其对CSR的影响 这在艾滋病的目标定位中起着重要作用。

The proposed research continues to focus on the mechanisms that regulate development of the high affinity antibody responses which are essential to vaccine development. There are several critical aspects to these responses that are entirely B cell specific. First, clonal expansion which occurs in special microanatomic structures called germinal centers (GC). Second, diversification of antibody genes by somatic mutation (SHM) and class switch recombination (CSR), both of which are initiated by activation induced cytidine deaminase (AID). Although AID prefers antibody genes, it is not entirely lg specific and off target activity is the primary cause of B cell cancers in humans. The third B cell specific aspect of high affinity antibody development is selection for clones of B cells that express high affinity receptors. In the first 4 years of the funding period, as part of the original Aims 1 and 2, we examined the mechanisms by which AID targets lg genes and misstargets cancer genes in the germinal center. Moreover, we documented the cellular and cell biological regulation of B cell clonal expansion in the germinal center. We have initiated research on Aim 3 and have made significant progress in understanding how Rif-1 mediates its effects on CSR by studying its interaction partner ZYMD8 which has an important role in AID targeting.