Spatial and Temporal Control of Tissue Growth using DNA Aptamers

The clinical need for improved craniofacial reconstruction materials drives the development of new tissue engineering scaffold materials to alleviate inherent problems with the current best practice, allo- and auto-grafting. Infoscitex, in collaboration with Tufts University and Alacer Biomedical, Inc., presents a novel silk fibroin derived scaffolding material, customizable to many form factors with tunable material properties, coated with cell-specific aptamers to promote selective affixation and controlled maturation of mesenchymal stem cells, with the goal of reducing wound healing time and promoting vascularization through the depth of the scaffold. In Phase I, we isolated aptamers that selectively bound to highly conserved identity regions of mesenchymal stem cells and affixed these aptamers to the surface of silk fibroin samples. Furthermore we demonstrated successful in vitro colonization of the scaffolds after a three-week culture. More detailed data on the effects of modified scaffolds on physiology of the affixed cells is being generated. In Phase II, we will perform in vivo studies and demonstrate that with the addition of embedded chemokine signals, angiogenesis through the scaffold is enhanced, and wound healing is more rapid and complete, and injured tissue reconstruction is effective.