Biodegradable porous silk microtubes for tissue vascularization

V.E. BOSIO; J. BROWN; M. J. RODRIGUEZ; D. L. KAPLAN

JOURNAL OF MATERIALS CHEMISTRY B

Royal Chemical Society

Lugar: Cambridge; Año: 2017 vol. 5 p. 1227 - 1235

2050-7518

Cardiovascular diseases are the leading cause of mortality around the globe, and microvasculaturereplacements to help stem these diseases are not available. Additionally, some vascular surgeriesneeding small-diameter vascular grafts present different performance requirements. In this work, silkfibroin scaffolds based on silk/polyethylene oxide blends were developed as microtubes for vasculatureneeds and for different tissue regeneration times, mechanical properties and structural designs. Systemswith 13, 14 and 15% silk alone or blended with 1 or 2% of polyethylene oxide (PEO) were used togenerate porous microtubes by gel spinning. Microtubes with inner diameters (IDs) of 150?300 mm and100 mm wall thicknesses were fabricated. The systems were assessed for porosity, mechanical properties,enzymatic degradability, and in vitro vascular endothelial cell attachment and metabolic activity. After14 days, all the tubes supported the proliferation of cells and the cell attachment increased with porosity.The silk tubes with PEO had similar crystallinity but a higher elastic modulus compared with the systemswithout PEO. The silk (13%)/PEO (1%) system showed the highest porosity (20 mm pore diameter onaverage), the highest cell attachment and the fastest degradation profile. There was a good correlationbetween these parameters with silk concentration and the presence of PEO. The results demonstratethe ability to generate versatile and tunable tubular biomaterials based on silk?PEO blends with potentialfor microvascular grafts.