Fig. 3

a Confocal image of a peptide/protein hydrogel (red) injected into the muscle of a dystrophic zebrafish (green) showing the localisation of the hydrogel within the tissue. TEM image shows the existence of the self-assembled fibrils in vivo. b Shows the integration of self-assembled peptide hydrogels within an injured spinal cord. AP staining (arrows) showed that blood vessels grew into the implants, whereas the fluorescent image shows the distribution of co-implanted GFP neural precursor cells within the matrix. Reprinted from Ref. [61]. Copyright (2007), with permission from Elsevier. c Longitudinal sections through the membrane conduit and the distal nerve end, respectively, at 3 weeks following sciatic nerve injury and repair. Regenerating axons are shown immunostained for βIII-tubulin (green) along with S100-positive Schwann cells (red) after transplantation of BD hydrogel with Schwann cells midconduit, and in the distal stump. Scale bar represents 100 and 25 μm. Reprinted from Ref. [60]. Copyright (2010), with permission from Elsevier. dArrow shows a 1 × 2 × 2 mm void cut into the right hemisphere of a rat brain, which, post bleeding, was filled with preformed SAP. Nissl and DAPI staining shows the lesion sites of the SAP. The dashed area indicates the extent of the SAP scaffold 6 weeks post implantation, demonstrating good integration with the brain tissue with no visible voids. Reprinted from Ref. [62]. Copyright (2009), with permission from Elsevier. e Scaffolds formed from IKVAV peptide amphiphiles promote the regeneration of motor axons after spinal cord injury. Neurolucida tracings of BDA-labeled descending motor fibers within a distance of 500 μm rostral of the lesion in vehicle-injected and IKVAV peptide amphiphile-injected animals, respectively, clearly showing the fibres crossing the injury in the presence of the self-assembled scaffold. The dotted lines demarcate the borders of the lesion reprinted with permission from Ref. [59]. Copyright (2008). f Shows a full-thickness osteochondral defect of a femoropatellar joint 12 weeks post injury. The defect is seen to regenerate when treated with a direct injection of SAP hydrogel. Reprinted from Ref. [65]. Copyright (2010), with permission from Elsevier. g Micrographs of the in vivo angiogenesis of rat cornea. Neovascularisation is not observed with growth factors alone, nor collagen and growth factors (not shown), whereas an injected hydrogel of heparin bound to a SAP networks (containing growth factors) shows an extensive effect. Reprinted with permission from Ref. [73]. Copyright (2006) American Chemical Society