TRANSGENIC ANIMAL MODELS USING YACS

GenPharm项目的目标是开发引入 酵母人工染色体（YACs）进入小鼠的生殖系， 将该技术应用于转基因小鼠的产生， 一种广泛的全人类免疫球蛋白库这些老鼠会允许 人单克隆抗体的分离与 啮齿动物单克隆抗体。 在第一阶段，开发了将YAC引入小鼠的方法， 而携带小YAC的小鼠编码最低能力的人类 显示免疫球蛋白转基因表达人重链IgM 血清中的抗体在第二阶段，第一阶段产生的动物 将完全表征转基因功能和表达。 将在YAC中克隆额外的恒定区和可变区，并添加 第一阶段YAC允许类别转换，体细胞突变， IgG生产。这些II期转基因将被引入小鼠体内 使用第一阶段开发的方法。转基因小鼠也将 产生携带未重排的人类kappa基因的大片段 并培育成II期重链小鼠。这些老鼠将与 缺乏功能性免疫球蛋白基因的小鼠， 广泛的高亲和力全人抗体库。

The goal of GenPharm's program is to develop methods for the introduction of yeast artificial chromosomes (YACs) into the germline of mice, and to apply the technology toward the generation of transgenic mice expressing a broad, fully human immunoglobulin repertoire. These mice would permit the isolation of human monoclonal antibodies in an analogous manner to rodent monoclonal antibodies. In Phase I, methods for the introduction of YACs into mice were developed, and mice carrying a small YAC encoding a minimally competent human immunoglobulin transgene were shown to express human heavy chain IgM antibodies in the serum. In Phase II, the animals generated in Phase I will be fully characterized for transgene function and expression. Additional constant and variable regions will be cloned in YACs and added to the Phase I YAC to permit class switching, somatic mutation, and IgGproduction. These Phase II transgenes will be introduced into mice using methodology developed in Phase I. Transgenic mice will also be generated carrying large fragments of the unrearranged human kappa gene and bred to the Phase II heavy chain mice. These mice will be bred with mice lacking functional immunoglobulin genes to produce mice demonstrating a broad repertoire of high affinity, fully human antibodies.