Enhancement of in vivo endothelialization of tissue‐engineered vascular grafts by granulocyte colony‐stimulating factor

Abstract

Successful reconstruction of large-diameter blood vessel in humans has been demonstrated using the tissue engineering technique, but improvement in patency of small-diameter bioartificial vascular graft remains a great challenge. This study reports that granulocyte colony-stimulating factor (G-CSF) can enhance in vivo endothelialization of tissue-engineered vascular grafts, which could be used to improve patency of small-diameter vascular graft. Vascular grafts were tissue engineered with decellularized canine abdominal aortas and canine autologous bone marrow-derived cells. Prior to cell seeding onto decellularized graft matrices, bone marrow-derived cells were induced to differentiate into endothelial cells and smooth muscle cells. The cell-seeded vascular grafts were implanted into the abdominal aortas of bone marrow donor dogs. Before and after graft implantation, G-CSF was administered subcutaneously to the dogs (n = 3). The grafts implanted into the dogs not receiving G-CSF were used as controls (n = 3). Eight weeks after implantation, grafts in both groups showed regeneration of vascular tissues including endothelium and smooth muscle. Importantly, endothelium formation was more extensive in the G-CSF-treated grafts than in the control grafts, as assessed with reverse transcription polymerase chain reaction, western blot, and immunohistochemistry. In addition, intimal hyperplasia was significantly reduced in the G-CSF-treated grafts compared to the control grafts. This study suggests that G-CSF administration could be applied to improve patency of small-diameter tissue-engineered vascular grafts.

Development and In Vivo Evaluation of Small-Diameter Vascular Grafts Engineered by Outgrowth Endothelial Cells and Electrospun Chitosan/Poly(ɛ-Caprolactone) Nanofibrous Scaffolds

“…Synthesized cDNA was amplified by PCR using the primers shown in Table 1. 32 For amplification, the following thermocycler program was used: 94°C for 2 min, 94°C for 30 s, annealing 60°C for 30 s, 72°C for 30 s, and 72°C for 10 min, repeated for 40 cycles from step 2 to step 4. The PCR products were resolved on 1.5% agarose gels (containing ethidium bromide at 0.5 mg/mL) and revealed at UV light.…”

Influence of the fiber diameter and surface roughness of electrospun vascular grafts on blood activation

“…While large diameter TEVG grafts regenerated successfully in humans with a five-years patency of about 90 % [5], small diameter vascular grafts (diameter < 5 mm) are still a challenge [6]. Among the main reasons for graft failure of small diameter grafts (anastomotic intimal hyperplasia, aneurysm formation, infection, and progression of atherosclerotic disease), acute thrombogenicity of the graft is one of the most important [7][8][9].…”

Tissue‐Engineered Blood Vessels With Endothelial Nitric Oxide Synthase Activity

“…Recently, it has been reported that BMCs are capable of differentiating into ECs [35][36][37] and vascular SMCs. [38][39][40] Indeed, BMCs have been shown as a feasible cell source for the engineering of cardiovascular tissues in animals 7,9,[16][17][18] and humans. 41,42 In addition, the use of BMCs as a cell source for vascular graft engineering is considered less invasive than harvesting vascular cells from autologous blood vessels.…”

“…[16][17][18] In brief, bone marrow (30 mL per dog) was aspirated from the humeri of healthy mongrel dogs (12 months old, 20-25 kg, n 5 7) with a syringe containing heparin (100 units heparin/mL bone marrow). Aspirated bone marrow was mixed with an equal volume of phosphate-buffered saline (PBS, Sigma, St. Louis, MO) solution and centrifuged on Ficoll-Paque density gradient (Amersham Biosciences, Arlington Heights, IL) for 30 min at 2000 rpm.…”