Abstract
Hydrogels are widely used matrices for mesenchymal stem cell (MSC)-based cartilage regeneration, but often result in slow deposition of cartilage extracellular matrix (ECM) components with inferior mechanical strength. We recently reported a macroporous, gelatin-based microribbon (μRB) scaffold, which substantially enhanced the speed of cartilage formation by MSCs in 3D. However, our previous method cannot be used to fabricate different polymers into μRBs and the effects of varying µRB composition on MSC cartilage regeneration in 3D remained unknown. Here, we report a method that allows fabricating different polymers (gelatin, chondroitin sulfate, hyaluronic acid, and polyethylene glycol (PEG)) into µRB structures, which can be mixed in any ratio and crosslinked into 3D scaffolds in a modular manner. Mixing glycosaminoglycan µRBs with gelatin or PEG µRBs induced great synergy, resulting in fast deposition of cartilage ECM components. After only three weeks of culture, leading mixed µRB composition reached high compressive strength on par with native cartilage. Such synergy can be recapitulated via exchange of soluble factors secreted by MSCs seeded in different µRB compositions in a dose-dependent manner. Tuning the ratio of mixed µRB compositions allowed further optimization of the quantity and speed of cartilage regeneration by MSCs. Together, our results validate mixed μRB compositions as a novel biomaterials tool for inducing synergy and accelerating MSC-based cartilage regeneration with biomimetic mechanical properties through paracrine signal exchange.
Funding Information
  • National Institute of Dental and Craniofacial Research (R01DE024772)
  • Stanford University
  • National Institute of Arthritis and Musculoskeletal and Skin Diseases (R01AR074502)

This publication has 48 references indexed in Scilit: