title: Engineering of vascular grafts with genetically modified bone marrow mesenchymal stem cells on poly (propylene carbonate) graft.
abstract: Bone marrow mesenchymal stem cells (MSCs) have demonstrated their pluripotency to differentiate into different cell lineages and may be an alternative cell source for vascular tissue engineering. The objective of this study is to create small diameter vessels by seeding and culture of genetically modified MSCs onto a synthetic polymer scaffold produced by an electrospinning technique. A tubular scaffold (2 mm in diameter) with a microstructure of nonwoven fibers was produced by electrospinning of poly (propylene carbonate) (PPC). Rat MSCs obtained from bone marrow were expanded in culture and modified with vasculoprotective gene endothelial nitric oxide synthase (eNOS) or marker gene green fluorescent protein (GFP). These MSCs were seeded onto the electrospun fibrous grafts (internal diameter = 2 mm), and cultured in 5% CO(2) at 37 degrees C. The growth of MSCs in the scaffold was analyzed with scanning electron microscopy (SEM) and hematoxylin and eosin (H&E) staining. The gene transfer and transgenic gene expression were examined with fluorescence-activated cell sorting (FACS), immunochemical staining, reverse transcriptase-polymerase chain reaction (RT-PCR), and western blot. The production of nitric oxide (NO) by the engineered vessels was measured with an NO detection kit. Our data showed that the seeded cells integrated with the microfibers of the scaffold to form a three-dimensional cellular network, indicating a favorable interaction between this synthetic PPC scaffold with MSCs. High transduction efficiency was obtained with the use of concentrated retrovirus in the gene transfection of MSCs. The eNOS gene transcripts and protein were detected in the grafts seeded with eNOS-modified MSCs by RT-PCR and immunochemical staining. The amount of NO produced by grafts seeded with eNOS-modified MSCs was comparable to that produced by native blood vessels, and it was significantly higher than that in the grafts seeded with nonmodified MSCs. In summary, the vascular graft produced by culture of eNOS gene-modified MSCs onto the electrospun tubular scaffolds shows promising results in terms of function. The use of MSCs and therapeutic genes in tissue engineering of blood vessels could be helpful in improving vessel regeneration and patency.
authors.affiliation: The Key Laboratory of Bioactive Materials, Ministry of Education, College of Life Science, Nankai University, Tianjin. China.
authors.forename: Jun
authors.initials: J
authors.lastname: Zhang
authors.forename: Hongxu
authors.initials: H
authors.lastname: Qi
authors.forename: Hongjun
authors.initials: H
authors.lastname: Wang
authors.forename: Ping
authors.initials: P
authors.lastname: Hu
authors.forename: Lailiang
authors.initials: L
authors.lastname: Ou
authors.forename: Shuhua
authors.initials: S
authors.lastname: Guo
authors.forename: Jing
authors.initials: J
authors.lastname: Li
authors.forename: Yongzhe
authors.initials: Y
authors.lastname: Che
authors.forename: Yaoting
authors.initials: Y
authors.lastname: Yu
authors.forename: Deling
authors.initials: D
authors.lastname: Kong
mesh_terms: D000818:Animals; D015153:Blotting, Western; D001854:Bone Marrow Cells / Q000166:cytology*; D018929:Cell Culture Techniques; D002454:Cell Differentiation; D004730:Endothelium, Vascular / Q000166:cytology*; D018014:Gene Transfer Techniques; D049452:Green Fluorescent Proteins / Q000235:genetics / Q000494:pharmacology; D059630:Mesenchymal Stem Cells / Q000166:cytology*; D008855:Microscopy, Electron, Scanning; D052250:Nitric Oxide Synthase Type III / Q000235:genetics / Q000494:pharmacology; D010957:Plasmids; D011126:Polypropylenes; D051381:Rats; D012190:Retroviridae; D020133:Reverse Transcriptase Polymerase Chain Reaction; D013194:Staining and Labeling; D055672:Static Electricity; D023822:Tissue Engineering / Q000379:methods*
chemical_list: D011126:Polypropylenes; D049452:Green Fluorescent Proteins; C039211:polypropylene carbonate; D052250:Nitric Oxide Synthase Type III