Collagen-Based Microcapsules As Therapeutic Materials for Stem Cell Therapies in Infarcted Myocardium.

As cell therapies emerged, it was quickly realized that pro-regenerative cells directly injected into injured tissue struggled within the inflammatory microenvironment. By using microencapsulation, i.e., encapsulating cells within polymeric biomaterials, they are henceforth protected from the harmful extracellular cues, while still being able to receive oxygen and nutrients and release secreted factors. Previous work showed that stem cells encapsulated within a biologically inert material (agarose) were able to significantly improve the function of the infarcted mouse heart. With the aim of using more bioresponsive microcapsules, we sought to develop an enzymatically degradable, type I collagen-based microcapsule for the intramyocardial delivery of bone marrow-derived mesenchymal stromal cells in a murine model of myocardial infarction.