EVOLUTION OF B PRECURSOR LEUKEMIA IN THE EU-RET MOUSE

描述：（逐字改编自研究者摘要）E（-ret 小鼠携带产生嵌合蛋白Rfp-Ret的转基因， 在B谱系细胞中的组成型酪氨酸激酶活性。成年E-ret小鼠 发展出B前体白血病，这些白血病似乎是由 胎儿来源的前B细胞。此外，白血病对刺激有抵抗力， 诱导胎儿和幼年E（-ret）小鼠前B细胞凋亡。的 申请人假设Rfp-Ret产物选择性地增强 胎儿来源的前B细胞的增殖和存活， 转化依赖于其他突变的积累， 进一步增强这些生长特性。该提案的目标是更多 彻底表征E（-ret）中白血病发生的多步骤过程 老鼠.在目标1中，他将确定胎儿和成人的前B细胞是否不同 对Rfp-Ret转基因产物转化的敏感性。他 将胎儿和成年E（-ret pro B细胞转移到Rag-1-小鼠中以确定 这些人群诱发白血病的能力是否不同。在目标2中， 他将确定Rfp-Ret活性是否模拟骨髓的作用， 基质接触他将确定Rag-1小鼠的前B细胞是否获得 当基质细胞表达IL-7时，它们在IL-7中生长而不接触基质细胞的能力 Rfp-Ret产物（E（-ret/Rag-1-）），并将确定Rfp-Ret是否增强 IL-7的增殖作用。在目标3中，他将确定 前B细胞中干扰素（IFN）-β抗性的发展使得 恶性生长他将从晚期肿瘤细胞中分离出抗IFN-β的细胞。 前B细胞群体的健康成年E（-ret小鼠，并测序 IFN-γ抗性细胞的重排免疫球蛋白重链基因座 确定这些细胞是否代表多克隆（未转化）或克隆 （变形）生长。在目标4中，他将确定 Rfp-Ret活性在转化过程中增加。他将 从胎儿和健康人的前B细胞群免疫沉淀Rfp-Ret 成年E（-ret）小鼠以及白血病，并比较酪氨酸水平 Rfp-Ret和Rfp-Ret结合蛋白的磷酸化。

DESCRIPTION: (adapted verbatim from the investigator's abstract) The E(-ret mouse carries a transgene that produces a chimeric protein, Rfp-Ret with constitutive tyrosine kinase activity in B lineage cells. Adult E(-ret mice develop B precursor leukemias that appear to arise from the progeny of fetal-derived pro B cells. Furthermore, the leukemias are resistant to stimuli that induce apoptosis in the pro B cells from fetal and young E(-ret mice. The applicant hypothesizes that the Rfp-Ret product selectively enhances the proliferation and survival of fetal-derived pro B cells, and that transformation is dependent on the accumulation of other mutations which further enhance these growth properties. The goals of this proposal are to more thoroughly characterize the multistep process of leukemogenesis in the E(-ret mouse. In aim 1, he will establish whether fetal and adult pro B cells differ in their susceptibility to transformation by the Rfp-Ret transgene product. He will transfer fetal and adult E(-ret pro B cells into Rag-1- mice to determine whether these populations differ in their ability to induce leukemia. In aim 2, he will establish whether Rfp-Ret activity mimics the effect of bone marrow stromal contact. He will determine whether pro B cells from Rag-1- mice acquire the ability to grow in IL-7 without stromal cell contact when they express the Rfp-Ret product (E(-ret/Rag-1-), and will determine whether Rfp-Ret enhances the proliferative effect of IL-7. In aim 3, he will establish whether the development of interferon (IFN)-( resistance in pro B cells allows for malignant outgrowth. He will isolate IFN-( resistant cells from within the late pro B cell populations of healthy adult E(-ret mice, and sequence the rearranged immunoglobulin heavy chain loci of the IFN-( resistant cells to determine whether these cells represent a polyclonal (nontransformed) or clonal (transformed) outgrowth. In aim 4, he will establish whether the level of Rfp-Ret activity increases during the transformation process. He will immunoprecipitate Rfp-Ret from the pro B cell populations of fetal and healthy adult E(-ret mice as well as from leukemias and compare the levels of tyrosine phophorylation of Rfp-Ret and Rfp-Ret-bound proteins.