Stanford University researchers reported that vascular organoid patches derived from human cells helped regenerate microvessels and improved heart function in pigs with ischemic heart disease. In a study published in Stem Cell Reports, Yasuhiro Shudo and colleagues implanted vascular organoid patches onto the surface of pig hearts and observed improved blood flow and preserved cardiac function versus untreated controls. The team co-cultured endothelial progenitor cells and smooth muscle cells differentiated from mesenchymal stem cells to drive microvessel network formation. The grafts survived for weeks, engrafted into deeper heart layers, and promoted increased vessel density and maturity, with corresponding changes in gene expression in the ischemic border zone. For regenerative medicine, the proof-of-concept supports the feasibility of human-derived vascular organoid patch therapy in large-animal models—an important step toward future translational work for microvascular disease.