Placental Endogenous Retrovirus Expression

胎盘内源性逆转录病毒表达

• 批准号: 6581818
• 负责人: NEAL STEWART ROTE
• 金额: $ 7.58万
• 依托单位: CASE WESTERN RESERVE UNIVERSITY
• 依托单位国家: 美国
• 财政年份: 2003
• 资助国家: 美国
• 起止时间: 2003-02-01 至 2005-01-31
• 项目状态: 已结题
• 来源: https://reporter.nih.gov/project-details/6581818
• 关键词: Retroviridae; biomaterial development /preparation; cell differentiation; cell line; clinical research; enzyme linked immunosorbent assay; human tissue; immunocytochemistry; laboratory mouse; messenger RNA; monoclonal antibody; placenta; polymerase chain reaction; technology /technique development; tissue /cell culture; transfection; trophoblast; virus protein

DESCRIPTION (provided by applicant): Approximately 1% of the human genome appears to be of retroviral origin. The purpose of these "endogenous" retroviral elements in human development remains unknown. A small number of organs express endogenous retroviruses under physiologic conditions; the human placenta is one of these. The normal human placental villous cytotrophoblast expresses differentiation-related transcription of the env region of a single copy endogenous retroviral genome (ERV-3). The strong association of ERV-3 expression with normal trophoblast differentiation suggests a physiologic role for ERV-3 in placental development. In support of this hypothesis, are the following observations. 1) ERV-3 env mRNA and Env protein are increased in syncytiotrophoblast and in spontaneously differentiating mononuclear villous cytotrophoblast. 2) Differentiation-related increase in ERV-3 env mRNA is concurrent with increased b-hCG mRNA and protein and intercellular fusion. 3) Transfection of BeWo choriocarcinoma cells, a model for trophoblast differentiation, with the sense strand of ERV-3 env resulted in a stable transfectant in which most aspects of trophoblast differentiation occurred: decreased growth, morphologic differentiation, and increased b-hCG mRNA and hCG protein production. 4) Transfection with the antisense strand decreased b-hCG mRNA production when the cells were induced to differentiate. These preliminary data support a hypothesis that ERV-3 env expression is an important step in the pathway of normal trophoblast differentiation, potentially through regulation of hCG expression. The specific aim of this R03 application is to accumulate adequate preliminary data for a successful R01 application to test this hypothesis, The individual specific Aims are: Aim 1) is to develop reagents, e.g.,monoclonal antibody and cell lines transfected with inducible plasmid systems, for studying the role of ERV3 env in villous trophoblast differentiation; Aim 2) is to determine whether ERV-3 env expression is necessary for differentiation of freshly isolated villous cytotrophoblasts; and Aim 3) is to determine whether ERV-3 env expression is inducible by steroids. These specific aims were chosen to address issues raised in previously unsuccessful R01 applications.

描述（由申请人提供）：大约 1% 的人类基因组似乎是逆转录病毒起源的。这些“内源性”逆转录病毒元件在人类发育中的作用仍然未知。少数器官在生理条件下表达内源性逆转录病毒；人类胎盘就是其中之一。正常人胎盘绒毛细胞滋养层表达单拷贝内源逆转录病毒基因组 (ERV-3) env 区域的分化相关转录。 ERV-3 表达与正常滋养层分化的密切相关表明 ERV-3 在胎盘发育中的生理作用。为了支持这一假设，有以下观察结果。 1) ERV-3 env mRNA和Env蛋白在合体滋养层和自发分化的单核绒毛细胞滋养层中增加。 2) ERV-3 env mRNA 分化相关的增加与 b-hCG mRNA 和蛋白质以及细胞间融合的增加同时发生。 3)用ERV-3 env的有义链转染BeWo绒毛膜癌细胞（滋养层分化的模型）产生稳定的转染子，其中发生了滋养层分化的大多数方面：生长减少、形态分化以及b-hCG mRNA和hCG蛋白产生增加。 4)当细胞被诱导分化时，用反义链转染减少了b-hCG mRNA的产生。这些初步数据支持这样一种假设：ERV-3 env 表达是正常滋养层分化途径中的重要一步，可能通过调节 hCG 表达来实现。 R03应用的具体目的是为成功的R01应用积累足够的初步数据来检验这一假设，具体目标是： 目标1)是开发试剂，例如单克隆抗体和用诱导型质粒系统转染的细胞系，用于研究ERV3 env在绒毛滋养层分化中的作用；目的2)是确定ERV-3 env表达对于新鲜分离的绒毛细胞滋养细胞的分化是否是必需的；目标 3) 是确定 ERV-3 env 表达是否可由类固醇诱导。选择这些具体目标是为了解决以前不成功的 R01 申请中提出的问题。