Development of a tissue-engineered vascular graft combining a biodegradable scaffold, muscle-derived stem cells and a rotational vacuum seeding technique

Abstract

There is a clinical need for a tissue-engineered vascular graft (TEVG), and combining stem cells with biodegradable tubular scaffolds appears to be a promising approach. The goal of this study was to characterize the incorporation of muscle-derived stem cells (MDSCs) within tubular poly(ester urethane) urea (PEUU) scaffolds in vitro to understand their interaction, and to evaluate the mechanical properties of the constructs for vascular applications. Porous PEUU scaffolds were seeded with MDSCs using our recently described rotational vacuum seeding device, and cultured inside a spinner flask for 3 or 7 days. Cell viability, number, distribution and phenotype were assessed along with the suture retention strength and uniaxial mechanical behavior of the TEVGs. The seeding device allowed rapid even distribution of cells within the scaffolds. After 3 days, the constructs appeared completely populated with cells that were spread within the polymer. Cells underwent a population doubling of 2.1-fold, with a population doubling time of 35 h. Stem cell antigen-1 (Sca-1) expression by the cells remained high after 7 days in culture (77+/-20% vs. 66+/-6% at day 0) while CD34 expression was reduced (19+/-12% vs. 61+/-10% at day 0) and myosin heavy chain expression was scarce (not quantified). The estimated burst strength of the TEVG constructs was 2127+/-900 mm Hg and suture retention strength was 1.3+/-0.3N. We conclude from this study that MDSCs can be rapidly seeded within porous biodegradable tubular scaffolds while maintaining cell viability and high proliferation rates and without losing stem cell phenotype for up to 7 days of in-vitro culture. The successful integration of these steps is thought necessary to provide rapid availability of TEVGs, which is essential for clinical translation.

In vivo determination of muscle-derived stem cells in rat corpus cavernosum

“…The present study detected the expression of Sca-1 and Oct4 in cavernous tissue and cells and the results were similar to the findings from non-corpus cavernosum-derived MDSCs reported by Nieponice et al (2008) and Ho et al (2009). The techniques presented in the present study can be used with previously established methods to identify corpus cavernosum stem cells and improve in their identification rate.…”

“…This is an important step in investigations of this type. We processed the corpus cavernosum tissues using enzymatic digestion, and the modified corpus Pre-plate differential adhesion technique was further utilized to isolate and purify the MDSCs according to Qu-Petersen et al (2002) and Nieponice et al (2008). The Pre-plate technique provides investigators with a rather homogenous sample of stem cells (Becker and Jakse, 2007).…”

Pluripotent Stem Cells and Their Dynamic Niche

“…Stiffer gels resembling muscle tissue enabled myogenic development and very stiff gels (25-40 kPa) replicating the bone properties resulted in osteogenic differentiation of MSC [264]. Similar observations were made by other researchers for two-dimensional and three-dimensional culture [265][266][267][268][269]. MSC incorporated into collagen-GAG scaffolds with stiffness of 0.5, 1 and 1.5 kPa exhibited different chondrogenic differentiation.…”

Mechanical characterization of a customized decellularized scaffold for vascular tissue engineering

“…If this goal can be achieved the probability of translating the technology to clinical application will be significantly improved. Attempts have been made to overcome this problem within synthetic scaffolds for vascular applications using rotational vacuum techniques (Soletti et al, 2006, Nieponice et al, 2008, Kasyanov et al, 2009, Godbey et al, 2004, the high porosity and large pore size make these scaffolds easier to seed with large cell numbers in short time periods. While in the case of dense decellularized tissue bulk seeding the medial layer has not been successfully achieved.…”