Gene product delivery by engineered somatic cells

描述（由申请人提供）：此R21申请是对项目公告PA-03-058的回应。本计划公告的既定目标是邀请探索性或发展性生物工程研究（EBRG）的申请。生物工程研究的一个例子是：药物、基因或细胞治疗递送系统的研究。本提案针对的就是这个例子。理想的基因产物传递系统应具有四个主要特征。(1)高效交付；（二）延长基因表达时间；（三）无毒性；(4)适用于整个患者群体，无需定制。在小鼠模型中，我们建议开发一种满足所有这些要求的基因传递系统。提出的治疗方法包括将mhc不匹配、表达转基因的基质细胞系注射到胸腺中。由于胸腺微环境的独特性（上文第4点），尽管存在MHC不匹配，但我们将确定受体小鼠是否对注射的细胞系具有耐受性。我们将检查受者，以确认注射的细胞留在注射部位（第1点），我们将监测基因产物的长期表达（第2点），同时寻找与胸腺中递送细胞存在相关的任何可能的病理（第3点）。在胸腺内注射转基因表达细胞后，长期基因产物递送可能会彻底改变许多单基因缺陷疾病的治疗。

DESCRIPTION (provided by applicant): This R21 application is in response to the program announcement PA-03-058. The stated objective of this program announcement is to invite applications in exploratory or developmental bioengineering research (EBRG). One listed example of bioengineering research is: Research on drug, gene, or cellular therapeutic delivery systems. This proposal addresses this example. The ideal gene product delivery system would have four main characteristics. (1) It should be delivered with high efficiency; (2) it should exhibit prolonged gene expression (3) it should be show no toxicity; and (4) it should be applicable to the entire patient population without any need for customization. Working in a murine model, we propose to develop a gene delivery system that meets all these requirements. The proposed therapy involves the injection of an MHC-mismatched, transgene-expressing stromal cell line into the thymus. We will establish whether the recipient mice are tolerant to the injected cell line, despite the MHC mismatch, due to the unique nature of the thymic microenvironment (point 4 above). We will examine the recipients to confirm that the injected cells remained at the site of injection (point 1), and we will monitor long-term expression of the gene product (point 2) while looking for any possible pathology related to presence of the delivery cells in the thymus (point 3). Long term gene product delivery following intrathymic injection of transgene-expressing cells could revolutionize treatment of a number of single gene defect disorders.