Sternal repair with bone grafts engineered from amniotic mesenchymal stem cells

Abstract

Background We aimed at determining whether osseous grafts engineered from amniotic mesenchymal stem cells (aMSCs) could be employed in postnatal sternal repair. Methods Leporine aMSCs were isolated, identified, transfected with green fluorescent protein (GFP), expanded, and seeded onto biodegradable electrospun nanofibrous scaffolds (n=6). Constructs were dynamically maintained in an osteogenic medium and equally divided into two groups with respect to time in vitro, namely 14.6 or 33.9 weeks. They were then used to repair full thickness sternal defects spanning 2–3 intercostal spaces in allogeneic kits (n=6). Grafts were submitted to multiple analyses 2 months thereafter. Results Chest roentgenograms showed defect closure in all animals, confirmed at necropsy. Graft density as assessed by micro-CT scans increased significantly in vivo, yet there were no differences in mineralization by extracellular calcium measurements pre- and post-implantation. There was a borderline increase in alkaline phosphatase activity in vivo, suggesting ongoing graft remodeling. Histologically, implants contained GFP-positive cells and few mononuclear infiltrates. There were no differences between the two construct groups in any comparison. Conclusions Engineered osseous grafts derived from amniotic mesenchymal stem cells may become a viable alternative for sternal repair. The amniotic fluid can be a practical cell source for engineered chest wall reconstruction.

Amniotic Fluid Progenitor Cells and Their Use in Regenerative Medicine

“…Expression of various osteogenic markers after 30 days in culture was demonstrated. Similar results were obtained by two other research groups (Antonucci et al, October 2009, Steigman et al, 2009and Sun et al, 2010. Peister in 2011 showed that AFSC were capable of a greater differentiation potential compared to mesenchymal stem cells although the latter response to the differentiative cocktail was occurring at earlier times (Peister et al, 2011).…”

Phenotype and ultrastructure of stem cells derived from amniotic fluid of Nitra rabbit

“…These two markers were not proposed by International Society for Cellular Therapy (ISCT; Dominici et al, 2006), however they are often used to detect MSC populations. There are many other studies of AF-MSCs, which found theses markers to be expressed in human (In't Anker et al, 2003;Tsai et al, 2004;De Coppi et al, 2007), rabbit (Steigman et al, 2009;Klein et al, 2010;DeKoninck et al, 2013;Fei et al, 2013;Kováč et al, 2016) and other species (Park et al, 2011;Chen et al, 2011;Nadri and Soleimani, 2007;Iacono et al, 2012;Choi et al, 2013). Investigators therefore use CD29 and CD44 together with some of molecular markers proposed for human MSCs by ISCT.…”

“…Although rAF-MSCs were previously defined by a few studies (Steigman et al, 2009;Klein et al, 2010;DeKoninck et al, 2013;Fei et al, 2013), some of the MSC markers, like CD73, CD105 and 166 were not previously screened in rAF-MSCs. A negative expression of surface markers detected by flow cytometry could also be possibly attributed to antibodies specificity.…”

“…To date, AF-MSCs have been isolated from various animal species for preclinical research (Steigman et al, 2009;Klein et al, 2010;Chen et al, 2011;Filioli Uranio et al, 2011;Choi et al, 2013;Colosimo et al, 2013). Regarding rAF-MSCs, there are reports demonstrating their isolation and characterization by a few molecular markers (Fei et al, 2013;Slamecka and Chrenek, 2013;Kováč et al, 2016) and showing their potential in preclinical research (Steigman et al, 2009;Klein et al, 2010).…”

“…Regarding rAF-MSCs, there are reports demonstrating their isolation and characterization by a few molecular markers (Fei et al, 2013;Slamecka and Chrenek, 2013;Kováč et al, 2016) and showing their potential in preclinical research (Steigman et al, 2009;Klein et al, 2010).…”