Fang Jianmin, Yi Saili, Simmons Andrew, Tu Guang Huan, Nguyen Minh, Harding Thomas C, VanRoey Melinda, Jooss Karin
Department of Preclinical Oncology and Immunology, Cell Genesys, Inc., South San Francisco, California 94080, USA.
Mol Ther. 2007 Jun;15(6):1153-9. doi: 10.1038/sj.mt.6300142. Epub 2007 Mar 20.
Monoclonal antibody (mAb) delivery by gene transfer in vivo may be an attractive alternative to current mAb therapies for applications that require long-term therapy. This article describes a transfer system that allows inducible high-level expression of unmodified mAbs in vivo. A recombinant adeno-associated viral (rAAV) vector is used that comprises an expression cassette consisting of a dimerizer-regulated promoter that drives expression of the antibody heavy and light chains linked by a 2A self-processing peptide and a furin cleavage site. Following intravenous injection of the rAAV vector, serum mAb levels >1 mg/ml were attained by administration of the inducer, rapamycin. Antibody expression could be rapidly shut off by discontinuing treatment with rapamycin. By optimizing the furin cleavage sequence, this system generated native antibody in vivo, decreasing the likelihood of a host immune response to foreign sequences. In summary, this optimized mAb expression system allows regulated high-level expression of native full-length mAbs in vivo and may offer a new opportunity for delivery of therapeutic mAbs in the clinic.
对于需要长期治疗的应用，通过基因转移在体内递送单克隆抗体（mAb）可能是当前mAb疗法的一种有吸引力的替代方案。本文描述了一种能够在体内诱导未修饰的mAb高水平表达的转移系统。使用了一种重组腺相关病毒（rAAV）载体，其包含一个表达盒，该表达盒由二聚体调节启动子组成，该启动子驱动通过2A自切割肽和弗林蛋白酶切割位点连接的抗体重链和轻链的表达。静脉注射rAAV载体后，通过给予诱导剂雷帕霉素，血清mAb水平达到>1mg/ml。通过停止雷帕霉素治疗，抗体表达可迅速关闭。通过优化弗林蛋白酶切割序列，该系统在体内产生天然抗体，降低了宿主对外源序列产生免疫反应的可能性。总之，这种优化的mAb表达系统允许在体内调节天然全长mAb的高水平表达，并可能为临床治疗性mAb的递送提供新的机会。
