Figure 8.

Injectable microribbon (μRB) hydrogels as carriers of stem cells for bone repair. (A) μRB hydrogel building blocks are fabricated using wet-spinning [ref] and can be crosslinked into microporous scaffolds in the presence of cells in situ. (B) Cell-laden μRBs are injected through a 16G needle to form a cell-laden, intact macroporous scaffold. (C) Scanning electron microscopy reveals the interconnected macroporosity of μRB scaffolds. (D) μRB scaffolds exhibit excellent mechanical flexibility and stability, withstanding cycles of compression up to 90% strain. (E) μRB scaffolds led to significantly higher cell survival than conventional hydrogels, with consistently higher cell numbers over 6 weeks. (n=4 per group, error-bars: standard deviations, p<0.05) (F-I) μRB-based scaffolds with adipose-derived stem cells (ADSCs) promote bone healing and bone-scaffold integration. Micro-computed tomography reveals that (F) stem cell-seeded uRB scaffolds led to significantly more mineralized bone formation in critical-size cranial defects than (G) conventional hydrogel controls. (H) Macroporosity in μRB scaffolds promoted more endogenous tissue integration than (I) nanoporous hydrogel scaffolds.

(A-I) Reproduced with permission. ^[60] Copyright 2016, John Wiley and Sons.