Artificial Niche Combining Elastomeric Substrate and Platelets Guides Vascular Differentiation of Bone Marrow Mononuclear Cells

Abstract

Bone marrow-derived progenitor cells are promising cell sources for vascular tissue engineering. However, conventional bone marrow mesenchymal stem cell expansion and induction strategies require plating on tissue culture plastic, a stiff substrate that may itself influence cell differentiation. Direct scaffold seeding avoids plating on plastic; to the best of our knowledge, there is no report of any scaffold that induces the differentiation of bone marrow mononuclear cells (BMNCs) to vascular cells in vitro. In this study, we hypothesize that an elastomeric scaffold with adsorbed plasma proteins and platelets will induce differentiation of BMNCs to vascular cells and promote vascular tissue formation by combining soft tissue mechanical properties with platelet-mediated tissue repairing signals. To test our hypothesis, we directly seeded rat primary BMNCs in four types of scaffolds: poly(lactide-co-glycolide), elastomeric poly(glycerol sebacate) (PGS), platelet-poor plasma-coated PGS, and PGS coated by plasma supplemented with platelets. After 21 days of culture, osteochondral differentiation of cells in poly(lactide-co-glycolide) was detected, but most of the adhered cells on the surface of all PGS scaffolds expressed calponin-I and a-smooth muscle actin, suggesting smooth muscle differentiation. Cells in PGS scaffolds also produced significant amount of collagen and elastin. Further, plasma coating improves seeding efficiency, and platelet increases proliferation, the number of differentiated cells, and extracellular matrix content. Thus, the artificial niche composed of platelets, plasma, and PGS is promising for artery tissue engineering using BMNCs.

Vascular Grafting Strategies in Coronary Intervention

“…Although increased cell proliferation was observed with platelet supplementation, and hence ECM secretion, the authors did not report the impact of platelets on the differentiation of stem cells into mature ECs. vWf immunohistochemistry revealed the presence of the blood glycoprotein in platelets (Wu et al, 2011), but its absence at the luminal surface, as expected in ECs, perhaps suggests that the platelets did not actively recruit the EPCs from BM-MNCs, or that the BM-MNCs preferentially differentiated into SMCs.…”

Heart valve tissue engineering: how far is the bedside from the bench?

“…160) or other proteins such as growth factors, which enable targeted promotion of particular tissue growth (Ref. 28).…”

“…204), or coated with plasma or platelet-enriched-plasma (Ref. 160), but this was not the case of fibrin-coated synthetic scaffolds. BMMCs seeded and incubated with them for short amounts of time did not increase cell integration after implantation neither in sheep (Ref.…”

Repair of critical-sized bone defects with anti-miR-31-expressing bone marrow stromal stem cells and poly(glycerol sebacate) scaffolds

“…The thickness of the salt layer, which determined the thickness of the final scaffold, was easily adjusted by inserting a combination of shims of different thicknesses. The physical properties of PGS scaffolds, such as their mechanical properties and the porosity, have been systematically investigated before Crapo et al, 2008;Wu et al, 2011). Finally, the disc-shaped (Φ 8 mm x 2 mm 3 ) porous PGS scaffolds were used for cell seeding.…”