Mouse models of severe combined immunodeficiencies

V(D)J重组缺陷是免疫缺陷和自身免疫疾病的基础 致癌。人类SCID的原因要么是T细胞发育缺陷，要么是T细胞和B细胞同时发育。 后一种疾病被称为T‘B’SCID，通常由V(D)J重组缺陷引起。空值 RAG-1或RAG-2的突变是大约一半人类结核病SCID的基础。亚形碎布 突变还会导致Omenn综合征(OS)，这是一种罕见的常染色体隐性遗传性SCID，通常表现为 带有自身免疫成分的“复杂”免疫缺陷。RAG突变导致的机制 对操作系统来说是未知的。本应用的主要目的是阐明正常RAG功能和异常RAG 通过表征RAG突变小鼠而可能导致复杂免疫缺陷和癌症的活动 台词。我们培育出的小鼠同时缺乏RAG1和RAG2的“非核心”区域 抑制转位和携带具有潜在连接缺陷的RAG1点突变的小鼠 这可能是致癌易位的诱因。我们将继续对这些老鼠进行分析，同时 产生额外的碎布敲入突变，包括几个建议允许碎布切割但已受损的突变 加入了。我们还将使用一种新的Abelson小鼠白血病病毒(A-MuLV)转化的Pro-B细胞系 作为感兴趣突变的体内快速筛查和RAG机制分析的基础的系统 蛋白质的功能。另一半的人类结核SCID有正常的RAG蛋白；但显示V(D)J 复合缺陷和增加的电离辐射敏感性。这个子集背后的缺陷是 编码Artemis、XLF和DMALigase 4非同源DMA末端连接的基因突变 各种因素。人类Artemis突变完全使该基因失活；而人类Lig4突变则完全失活 亚形的。目前尚不清楚已知的人类XLF突变是否完全使该基因失活。我们 之前为Artemis缺乏症生成了小鼠模型，最近为两者生成了小鼠模型 XLF和亚型Ligase 4缺乏。这项提案的其他主要目的是描述这些 新的模型来阐明这些NHEJ因子的正常功能，并再次确定突变是如何在 这些基因导致了各种人类免疫缺陷综合症，并可能导致癌症。 我们的免疫系统根据一个过程识别和消灭大量的外来入侵者 其中无限数量的抗体基因是通过剪切和粘贴基因盒而形成的。中的缺陷 进行这种剪切和粘贴过程的蛋白质的编码基因会导致免疫缺陷 (感染的易感性)。我们提出的研究旨在为此类人类疾病建立小鼠模型。 以更好地了解剪切和粘贴蛋白的功能，并开发更好的治疗方法。 儿童医院 卡普家庭研究实验室 9楼 一个Blackfan圆环 马萨诸塞州波士顿，邮编02115 小灵通398(04/06版)页面格式第2页 首席调查员/项目主任(最后、第一、中间)：TeitlOrst，Comelis P.I.Alt，Frederick W. 关键人员。请参阅说明。根据需要使用续页，以如下所示的格式提供所需信息。 从首席调查员(S)开始。按字母顺序列出所有其他关键人员，姓氏在前。 名称时代公用项项目上的用户名组织角色 弗雷德里克·W·弗雷达特儿童基金会

V(D)J recombination defects underlie diseases ranging from immunodeficiency and auto-immunity to cancer. Human SCIDs result either from defects in T cell development or both T and B cell development. The latter disease, referred to as T'B'SCID, generally results from V(D)J recombination defects. Null mutations in RAG-1 or RAG-2 are the basis for about half of the human TB'SCIDs. Hypomorphic RAG mutations also cause Omenn syndrome (OS), a rare autosomal recessive SCID that often presents as a "complex" immunodeficiency with an auto-immune component. Mechanisms by which RAG mutations lead to OS are unknown. A major aim of this application is to elucidate normal RAG functions and aberrant RAG activities that could lead to complex immunodeficiency and cancer by characterizing RAG mutant mouse lines. We have generated mice that lack both the "non-core" RAG1 and RAG2 regions implicated in suppressing transpositions and a mouse carrying a RAG1 point mutation that has a potential joining defect that may predispose to oncogenic translocations. We will continue analyses of these mice and also generate additional RAG knock-in mutations including several proposed to allow RAG cutting but impaired joining. We also will employ a novel Abelson Murine Leukemia virus (A-MuLV)-transformed pro-B cell line system as a rapid in vivo screen for mutations of interest and as a basis for mechanistic analyses of RAG protein functions. The other half of human TB'SCIDs have normal RAG proteins; but show V(D)J recombination defects and increased ionizing radiation-sensitivity. The defects underlying this subset are mutations in genes that encode the Artemis, XLF and DMALigase 4 non-homologous DMA end-joining factors. Human Artemis mutations completely inactivate the gene; whereas human Lig4 mutations are all hypomorphic. It is not yet clear whether known human XLF mutations completely inactivate the gene. We previously generated a mouse model for Artemis deficiency and recently generated mouse models for both XLF and hypomorphic Ligase 4 deficiency. The other major aims of this proposal are to characterize these new models to elucidate normal functions of these NHEJ factors and, again, to determine how mutations in these genes contribute to various human immunodeficiency syndromes and potentially to cancer. Our immune system recognizes and eliminates a vast array of foreign invaders based on a process in which limitless numbers of antibody genes are formed by cutting and pasting gene cassettes. Defects in human genes that code for proteins that carry out this cutting and pasting process cause immunodeficiency (susceptibility to infection). Our proposed research seeks to make mouse models for such human diseases to better understand the functions of the cutting and pasting proteins and to develop better therapies. Children's Hospital Karp Family Research Laboratories 9th Floor One Blackfan Circle Boston, MA 02115 PHS 398 (Rev. 04/06) Page Form Page 2 Principal Investigator/Program Director (Last, First, Middle): TeitlOrst, ComeliS P.I Alt, Frederick W. KEY PERSONNEL. See instructions. Use continuation pages as needed to provide the required information in the format shownbelow. Start with Principal Investigator(s). List all other key personnel in alphabetical order, last name first. Name eRA CommonsUser Name Organization Role onProject Alt, Frederick W. FREDALT Children'