Dual-regulated Lentiviral Vector for Gene Therapy of X-linked Chronic Granulomatosis

作者：Chiriaco Maria; Farinelli Giada; Capo Valentina; Zonari Erika; Scaramuzza Samantha; Di Matteo Gigliola; Sergi Lucia Sergi; Migliavacca Maddalena; Hernandez Raisa Jofra; Bombelli Ferdinando; Giorda Ezio; Kajaste Rudnitski Anna; Trono Didier; Grez Manuel; Rossi Paolo; Finocchi Andrea; Naldini Luigi; Gentner Bernhard; Aiuti Alessandro^*

来源：Molecular Therapy, 2014, 22(8): 1472-1483.

DOI：10.1038/mt.2014.87

Regulated transgene expression may improve the safety and efficacy of hematopoietic stem cell (HSC) gene therapy. Clinical trials for X-linked chronic granulomatous disease (X-CGD) employing gammaretroviral vectors were limited by insertional oncogenesis or lack of persistent engraftment. Our novel strategy, based on regulated lentiviral vectors (LV), targets gp91(phox) expression to the differentiated myeloid compartment while sparing HSC, to reduce the risk of genotoxicity and potential perturbation of reactive oxygen species levels. Targeting was obtained by a myeloid-specific promoter (MSP) and posttranscriptional, microRNA-mediated regulation. We optimized both components in human bone marrow (BM) HSC and their differentiated progeny in vitro and in a xenotransplantation model, and generated therapeutic gp91(phox) expressing LVs for CGD gene therapy. All vectors restored gp91(phox) expression and function in human X-CGD myeloid cell lines, primary monocytes, and differentiated myeloid cells. While unregulated LVs ectopically expressed gp91(phox) in CD34(+) cells, transcriptionally and post-transcriptionally regulated LVs substantially reduced this off-target expression. X-CGD mice transplanted with transduced HSC restored gp91(phox) expression, and MSP-driven vectors maintained regulation during BM development. Combining transcriptional (SP146.gp91-driven) and posttranscriptional (miR-126-restricted) targeting, we achieved high levels of myeloid-specific transgene expression, entirely sparing the CD34+ HSC compartment. This dual-targeted LV construct represents a promising candidate for further clinical development.

• 出版日期2014-8