Ex vivo-transduced autologous skin fibroblasts expressing human Lim mineralization protein-3 efficiently form new bone in animal models

Abstract

Local gene transfer of the human LIM Mineralization Protein (LMP), a novel intracellular positive regulator of the osteoblast differentiation program, can induce efficient bone formation in rodents. In order to develop a clinically relevant gene therapy approach to facilitate bone healing, we have used primary dermal fibroblasts transduced ex vivo with Ad.LMP3 and seeded on an hydroxyapatite/collagen matrix prior to autologous implantation. Here we demonstrate that genetically modified autologous dermal fibroblasts expressing Ad.LMP-3 are able to induce ectopic bone formation following implantation of the matrix into the mouse triceps and paravertebral muscles. Moreover, implantation of the Ad.LMP-3-modified dermal fibroblasts into a rat mandibular bone critical size defect model results in efficient healing as determined by X-ray, histology and three dimensional micro computed tomography (3DμCT). These results demonstrate the effectiveness of the non-secreted intracellular osteogenic factor LMP-3, in inducing bone formation in vivo. Moreover, the utilization of autologous dermal fibroblasts implanted on a biomaterial represents a promising approach for possible future clinical applications aimed at inducing new bone formation.

Comparative efficacy of dermal fibroblast-mediated and direct adenoviral bone morphogenetic protein-2 gene therapy for bone regeneration in an equine rib model

“…A Ishihara et al use of different osteogenic genes such as Runx2, 11 BMP7 13 and Lim mineralization protein-3 15 may further improve the osteoinductive capacity of DFb-mediated gene therapy.…”

“…Although embryonic and adult mesenchymal stem cells have been extensively studied for cell-mediated gene therapy, 8,9 other cell sources, such as dermal fibroblasts (DFbs) may be an alternative candidate because of their excellent reprogramming capacity. 10 In fact, DFbs have been differentiated into bone-forming cells by the transduction of osteogenic genes including BMP2, [11][12][13][14][15] and such genetically modified DFbs have been autologously transplanted to induce ectopic bone formation 14,15 and promote bone healing in rodent models. 12,13,15 In contrast to the use of stem cells, skin cell-mediated therapy is attractive for clinical use because of the relatively less painful harvest technique, low risk of donor site infection or morbidity, less fastidious culture procedure and rapid high cell yield.…”

“…10 In fact, DFbs have been differentiated into bone-forming cells by the transduction of osteogenic genes including BMP2, [11][12][13][14][15] and such genetically modified DFbs have been autologously transplanted to induce ectopic bone formation 14,15 and promote bone healing in rodent models. 12,13,15 In contrast to the use of stem cells, skin cell-mediated therapy is attractive for clinical use because of the relatively less painful harvest technique, low risk of donor site infection or morbidity, less fastidious culture procedure and rapid high cell yield. [12][13][14][15] Therefore, the use of DFb may be considered as one choice of cell type for ex vivo gene therapy, although the osteoinductive capacity may not be superior to stem cells.…”

“…12,13,15 In contrast to the use of stem cells, skin cell-mediated therapy is attractive for clinical use because of the relatively less painful harvest technique, low risk of donor site infection or morbidity, less fastidious culture procedure and rapid high cell yield. [12][13][14][15] Therefore, the use of DFb may be considered as one choice of cell type for ex vivo gene therapy, although the osteoinductive capacity may not be superior to stem cells.…”

Progress and Prospects: genetic treatments for disorders of bones and joints

“…Osterix, 35 and lim mineralization protein-3 36 cDNAs have recently been shown to be effective when delivered by the ex vivo route in various experimental models. These transgenes are well suited for gene transfer because they encode Genetic treatments for disorders of bones and joints CH Evans et al intracellular proteins that are otherwise difficult to administer.…”