Figure 1. Application of biomaterials in repairing stroke brain.

(A) Biomaterials enable local release of factors and/or provide structural support in case of tissue loss. The least invasive means to deliver factors to the stroke damage brain is by the epi-cortical placement of biomaterials, such as hydrogel, releasing factors into the surrounding cortex (I.). Hydrogels can also serve as a scaffolding material in the lesion cavity (II.). An injection-drainage approach is preferable to ensure homogenous filling of the volume. Repair response in the peri-infarct area can be influenced by injecting microparticles that release growth factors, and that would not easily penetrate across the blood-brain barrier (III.). Injection of microparticles into the lateral ventricle (IV.) can be used to influence the sub-ependymal zone to increase neurogenesis. (B) Exemplary overview immunofluorescent staining of brain slice showing ECM hydrogel (detected by collagen I in green) in the lesion cavity.