Editorial: Tissue repair and regenerative mechanisms by stem/progenitor cells and their secretome

Tissue Repair and Regenerative Mechanisms by Stem/Progenitor Cells and Their Secretome Regenerative medicine is a branch of translational research which is energizing and empowering clinical practice. A multitude of novel approaches proposed during the recent years is slowly but dramatically transforming the health care system, harnessing the power of repairing, replacing, restoring, and regenerating human organs and tissues affected by various degenerative disorders and diseases. During the twentieth century, hundreds of thousands of patients with end-stage diseases have been rescued by solid organ transplants as ultimate treatment option. In the past 3 decades, cell-based therapies have been gaining importance since they can contribute to regeneration of failing organs or damaged tissues by direct replacement of the lost cells or by facilitating the body’s natural regenerative processes by removing roadblocks. A growing armamentarium of therapeutic options, spanning from bioartificial organs and tissues, stem and progenitor cells, biomaterials, cell secretome, and extracellular vesicles have become available as medical treatments substituting the standard pharmaceutics. Examples of “classical” cellular therapies are peripheral blood stem cell or stromal cell transplantations, and more recently, allogenic hepatocyte or pancreatic islet transplants. While pancreas transplantation remains the gold standard in diabetes patients where the insulin injection fails to control symptoms, transplantation of islets of Langerhans has been recognized as a successful cell-based treatment in type 1 diabetes. The mechano-enzymatic separation of endocrine tissue from the exocrine pancreatic parenchyma required several decades to become a standardized clinical approach approved by Medical Product Agencies worldwide.