Injury-Free In Vivo Delivery and Engraftment into the Cornea Endothelium Using Extracellular Matrix Shrink-Wrapped Cells

Cell injection has emerged as a widespread approach for therapeutic delivery of healthy cells into diseased and damaged tissues to achieve regeneration. However, cell retention, viability and integration at the injection site has generally been poor, driving the need for improved approaches. Additionally, it is unknown how efficiently single cells can integrate and repair tissue level function. Here we have developed a technique to address these issues by engineering islands of interconnected cells on ECM nanoscaffolds that can be non-destructively released from the surface via thermal dissolution of the underlying thermo-responsive polymer. Upon dissolution of the polymer, the ECM nanoscaffold shrink-wraps around the small island of cells, creating a small patch of cells that maintain their cell-cell junctions and cytoskeletal structure throughout collection, centrifugation and injection that we have termed Monolayers. These Monolayers were made with corneal endothelial cells, as a model system, as single cell injections of corneal endothelial cells have been used with some success clinically to treat corneal blindness. In vitro our Monolayers exhibited increased integration compared to single cells into low density corneal endothelial monolayers and in vivo into the high-density healthy rabbit corneal endothelium. These results indicate that this technique could be used to increase the integration of healthy cells into existing tissues to treat not only corneal blindness, but also other conditions such as cystic fibrosis, myocardial infarction, diabetes, etc. One Sentence SummarySmall monolayers of interconnected endothelial cells are shrinkwrapped in a thin layer of ECM and exhibit enhanced adhesion and integration in vivo compared to single cell suspensions.