Behavior of Human Mesenchymal Stem Cells in Fibrin-Based Vascular Tissue Engineering Constructs

Abstract

A limitation of current tissue engineering vascular graft technology is the provision of an expandable, autologous cell source. By harnessing the multipotency of mesenchymal stem cells (MSC), it is hoped that functional vascular cells can be produced. To date, a range of 2D and 3D environments have been investigated for the manipulation of MSC differentiation pathways. To this end, this study aims to test the hypothesis that MSC seeded in various fibrin gel environments will exhibit evidence of a smooth muscle cell (SMC) phenotype. Initially, a range of cell-seeding densities were screened for 2D and 3D fibrin constructs, where it was observed that a seeding densities of 500,000 cells/mL facilitated gel compaction without degradation or loss in cell viability. Additionally, positive expression of CD49, CD73, CD105 markers and negative expression of hemopoietic stem cell-associated CD34 and CD45 indicated that MSC phenotype was retained within the fibrin gel. Nonetheless, a decrease in the gene expression of alpha-smooth cell actin and calponin was observed for MSC cultured in static 3D fibrin gels. Although a slight recovery was observed after 24 h mechanical stimulation, the fold-change remained significantly lower than that observed for cells cultured on 2D tissue culture plastic. While MSC differentiation toward a SMC appears possible in both 2D and 3D environments, scaffold architecture and mechanical stimulation undoubtedly play an important role in the creation of a functional SMC phenotype.

Adipose stem cell combined with plasma-based implant bone tissue differentiation in vitro and in a horse with a phalanx digitalis distalis fracture: a case report

“…This technology is often used for connecting tissue fragments during orthopaedic reconstructions; due to its natural bacteriostatic capabilities and viscoelastic properties, this method has now become widely used (Falanga et al 2007;Kalbermatten et al 2008;O'Cearbheill et al 2010;Seybold et al 2010). When prepared correctly, this technique creates a natural biodegradable scaffold for cell growth and differentiation, (Bansa et al 2003).…”

The role of mechanical stimuli in the vascular differentiation of mesenchymal stem cells

“…SMC-associated markers (O'Cearbhaill et al, 2010). Although 2D uniaxial strain induces a different response from that of the in vivo situation in terms of cell alignment, it is nevertheless more effective in mediating differentiation than cyclic strain applied in a 3D model.…”

“…It is thus clear that additional 3D models need to be developed which are able to better replicate in vivo conditions and thus might be more effective in directing differentiation towards SMCs (Smith and Gerecht, 2014). In the case of rat and human MSCs, cyclic strain alone has been shown to induce the expression of some but not all SMC markers, in particular markers of mature SMCs such as SMMHC (Nieponice et al, 2007;Hamilton et al, 2004;Ghazanfari et al, 2009;O'Cearbhaill et al, 2010). In order to increase differentiation efficiency, cyclic strain can be applied in combination with other factors, such as growth factors.…”

European Society of Biomechanics S.M. Perren Award 2012: The external mechanical environment can override the influence of local substrate in determining stem cell fate

“…One such natural hydrogel which facilitates integrin binding to ligands present on the scaffold is fibrin (Janmey et al, 2009). Fibrin has been shown to support chondrogenic differentiation (Li et al, 2009;Pelaez et al, 2009), but it similarly facilitates osteogenic (Catelas et al, 2006;Weinand et al, 2006) and myogenic (Nieponice et al, 2007;O'Cearbhaill et al, 2010) differentiation of MSCs.…”