An experimental mouse model of spontaneous generation of HodgkinDisease by introduction of GANP RNA-primase gene

我们研究了诱导小鼠淋巴瘤的分子。β RNA引发酶GANP发现于生殖中心B细胞中，其在体内用T细胞依赖性抗原免疫刺激后快速增殖和成熟。GANP小鼠的损失没有表现出明显的异常，但表现出缺乏产生高亲和力抗体的生产，减少免疫球蛋白的体细胞超突变。V区基因相对于抗原刺激。这些小鼠缺乏高亲和力类型的突变。GANP的作用进一步通过使用转基因策略的GANP的过表达得到证实，这清楚地表明了抗原驱动的B细胞中增强的体细胞超突变率和高亲和力类型的突变。为了进一步证明这一点，我们通过在单克隆水平上测量特异性抗体的亲和力来研究抗体的亲和力。用硝基苯基-鸡G-球蛋白免疫后，产生了6000多株单克隆抗体 ...更多信息 建立分泌抗NP特异性抗体的杂交瘤细胞株。GANP-Tg小鼠产生的单克隆抗体与半抗原NP的亲和力较高，KD× 109 M，而野生型同窝对照的亲和力较低。有趣的是，在O 57 BL/6小鼠系统中，使用具有更多体细胞超突变的V区和使用非经典V区基因产生了高亲和力的单克隆抗体。这些结果表明，GANP通过调节B细胞克隆性扩增过程中V区突变的诱导和/或DNA损伤的修复，参与了抗原免疫后高亲和力B细胞的产生，并在增殖中心区进行选择。人霍奇金淋巴瘤Read-Sternberg细胞表达量较高。该单克隆抗体可用于检测人类HD临床样本中经常观察到的淋巴瘤混合群体中的恶性细胞。我们研究了GANP表达的增加是否可能是小鼠淋巴瘤的致病因素。GANP-Tg在老年组自发产生与人类HD淋巴瘤非常相似的非B/非T细胞型淋巴瘤。提示GANP表达增强和异常是小鼠HD样淋巴瘤的一个致病因素。我们推测，额外的因素参与淋巴瘤的产生，可能与各种病毒的感染和外周淋巴器官免疫系统的应激有关。少

We investigated the molecule that induces lymphomas in mouse. Beta RNA primase GANP was found in germinal center B cells that are rapidly proliferating and maturating upon stimulation with T cell-dependent antigen immunization in vivo. Loss of GANP mice displayed no apparent abnormalities but showed a lack of generation of high-affinity antibody production with reduced somatic hypermutation of immunogolobulin. V-region genes with respect to the antigen stimulation. The mice lacked the high-affinity type mutations. The effect of GANP was further confirmed by the over expression of GANP using transgenic strategy, that clearly indicated the augmented somatic hypermutation rates and the high-affinity type mutations in antigen driven B cells. To prove this further, we studied the affinity of the antibodies by measuring the affinity of the specific antibodies at the monoclonal level. More than 6000 monoclonal antibodies were generated after immunization with nitrophenyl-chicken g-globulin an … More d establishment of the hybridomas secreting anti-NP specific antibodies. GANP-trangenic (GANP-Tg) mice generated the monoclonal antibodies with higher affinity to the hapten NP as KD×109M in comparison with the lower affinities from the wild-type littermate controls. Interestingly, the high affinitymonoclonal antibodies were generated by the V-regions with more somatic hypermutations and using the non-canonical V-region gene in a system of O57BL/6 mice system. These results indicated that GANP is involved in generation of high-affinity B cells upon immunization with antigen by regulating the induction of V-region mutations and/or the repair of the DNA damage during B cell clonal expansion and the selection in germinal center regions.The expression of GANP was detected extremely high in the lymphoma specimens by histochemical analysis with anti-GANP specific and the phosphorylated GANP-specific monoclonal antibodies. Human Hodgkin lymphoma, Read-Sternberg cells displayed the higher expression. The monoclonal antibodies were useful for detection of the malignant cells in the mixed population of the lymphomas often observed in human HD clinical samples. We examined whether the increased expression of GANP could be a causative factor of lymphomas in mice. GANP-Tg generated lymphomas of non-B/non-T cell type as quite similar to the human HD lymphomas spontaneously in aged group. These results indicated that the augmented and abnormal expression of GANP is a causative factor of lymphomas of HD-like lymphomas in mice. We speculated that the additional factors are involved in the generation of lymphomas, presumably associated with the infections with various viruses and the stresses of the immune system in peripheral lymphoid organs. Less