CHEMOTHERAPEUTIC INDUCTION OF SOMATIC MUTATION

我们最近开发了一种检测体细胞突变的系统 细胞在检测和定量这些方面特别有效 当存活的诱变剂暴露的细胞(或来自 这些细胞)很小(不到1,000个)。这个系统是在#年制定的。 培养的细胞，并基于对突变体的电泳检测 超过40个酶基因座。多个轨迹屏幕显示在 基因座的易感性(一些产生频率较高的突变 从10到-2再到诱变剂。结果还表明，基因座精致地 对某些诱变剂敏感的可能相对不受其他诱变剂的影响。 多标记变异无性系的亚克隆分析不仅建立 突变型的性质，也是揭示突变型最多的部门 很可能是由这种化学物质的延迟遗传效应引起的。考虑到 这些结果对躯体的作用等基本问题的影响 肿瘤转化中的突变与肿瘤细胞的遗传学基础 为了摆脱化疗的细胞毒性，这些研究需要 在体内推广、验证和应用。在这里，我们将重新申请 开发了直接从外周血中克隆T细胞的方法 暴露于化疗中的人的淋巴细胞。然后这些克隆人就会 通过我们的电泳系统来筛选酶基因座 变种人。然后，这些数据将被用于调查： 体外诱变模型及化疗药物的诱变作用 细胞变异性以及这种变异性对人类健康的影响 肿瘤和复发细胞的生物学起源。这项研究还应该 有效地开发动物遗传毒性检测系统 模特和男人。两种酶的电泳法筛选 基因座突变和T细胞克隆程序现在已经达成一致 发展到这样的程度，即它们结合在一起是独特有效的 并有能力回答这些问题。

We have recently developed a system for detecting mutations in somatic cells which is particularly efficient in detecting and quantitating such events when the number of surviving mutagen exposed cells (or clones from those cells) is small (less than 1,000). The system has been worked out in cultured -cells and is based on the electrophoretic detection of mutants at over 40 enzyme loci. The multiple locus screen indicated a wide range in the susceptibility of loci (some producing mutants at frequencies greater than 10 to the -2 to mutagens. Results also implied that loci exquisitely sensitive to some mutagens may be comparatively unaffected by others. Subclone analysis of multiply marked variant clones not only established the mutant nature of the variants, but also revealed mutant sectors most likely caused by a delayed genetic effect of the chemical. Considering the impact of such results on such fundamental problems as the role of somatic mutation in neoplastic transformation and the genetic basis of tumor cell escape from chemotherapeutic cytotoxicity, these studies need to be extended, verified, and applied in vivo. Here we shall apply newly developed methods to clone T cells directly out of peripheral blood lymphocytes of chemotherapeutically exposed humans. These clones will then be put through our electrophoretic system to screen for enzyme locus mutants. These data will then be used to investigate: the validity of the in vitro mutation model, effects of chemotherapeutic agents in inducing cell variability, and the consequences of such variability on human health and biological origin of tumor and relapse cells. The research should also be effective in developing systems for assaying genetic toxicity in animal models and man. Both the electrophoretic screening approach for enzyme locus mutants and the T cell cloning procedures have now reached concordant development to the extent that they, in combination, are uniquely efficient and capable of approaching these questions.