Genetic engineering of human stem cells for enhanced angiogenesis using biodegradable polymeric nanoparticles

Abstract

Stem cells hold great potential as cell-based therapies to promote vascularization and tissue regeneration. However, the use of stem cells alone to promote angiogenesis remains limited because of insufficient expression of angiogenic factors and low cell viability after transplantation. Here, we have developed vascular endothelial growth factor (VEGF) high-expressing, transiently modified stem cells for the purposes of promoting angiogenesis. Nonviral, biodegradable polymeric nanoparticles were developed to deliver hVEGF gene to human mesenchymal stem cells (hMSCs) and human embryonic stem cell-derived cells (hESdCs). Treated stem cells demonstrated markedly enhanced hVEGF production, cell viability, and engraftment into target tissues. S.c. implantation of scaffolds seeded with VEGF-expressing stem cells (hMSCs and hESdCs) led to 2- to 4-fold-higher vessel densities 2 weeks after implantation, compared with control cells or cells transfected with VEGF by using Lipofectamine 2000, a leading commercial reagent. Four weeks after intramuscular injection into mouse ischemic hindlimbs, genetically modified hMSCs substantially enhanced angiogenesis and limb salvage while reducing muscle degeneration and tissue fibrosis. These results indicate that stem cells engineered with biodegradable polymer nanoparticles may be therapeutic tools for vascularizing tissue constructs and treating ischemic disease.

Nanoparticle engineered TRAIL-overexpressing adipose-derived stem cells target and eradicate glioblastoma via intracranial delivery

“…Using a leading commercially available transfection reagent (Lipofectamine 2000), the highest transfection efficiency we achieved was ∼7.37 ± 0.96%, which is far from sufficient to achieve therapeutic efficacy for clinical application. Based on our recent work on biodegradable nanoparticle-mediated transfection in stem cells (23,24), we further systematically optimized the nanoparticle-fabrication formulation and the transfection protocol with our custom-developed amino group end-modified PBAEs. As shown via agarose gel electrophoresis, the DNA plasmid was completely condensed in polymer nanoparticles when the weight ratio of polymer and plasmid coded with recombinant enhanced GFP (pEGFP) in nanoparticles was greater than 10:1 (Fig.…”

Liposomes in tissue engineering and regenerative medicine

“…Lipofectamine, a leading commercial reagent, is a cationic liposome formulation commonly used to transfect cells [176]. However, their success in vivo as a gene therapy strategy has been limited due to the lack of colloidal stability, short duration of gene expression and cytotoxicity [175,177,178]. Cationic polymers have also been proposed as nonviral gene delivery systems, due to their flexible properties, facile synthesis, robustness and proven gene delivery efficiency.…”

VEGF Improves Skeletal Muscle Regeneration After Acute Trauma and Reconstruction of the Limb in a Rabbit Model

“…Furthermore, limb ischemia not only led to impaired angiogenesis, but also caused abnormal tissue fibrosis, as in our study. Conversely, the fibrotic area in the ischemic region was markedly reduced by injection of human mesenchymal stem cells transfected VEGF nanoparticles [32]. When VEGF was inhibited via its soluble antagonist (sFlt1), the level of angiogenesis was inhibited while an increase of fibrosis was observed [7].…”