Effects of microenvironment and biological behavior on the paracrine function of stem cells

Mesenchymal stem cells (MSCs), the most well-studied cell type in the field of stem cell therapy, have multi-lineage differentiation and self-renewal potential. MSC-based thera-pies have been used to treat diverse diseases because of their ability to potently repair tissue and locally restore function. An increasing body of evidence demonstrates that paracrine func-tion is central to the effects of MSC-based therapy. Growth factors, cytokines, chemokines, extracellular matrix components, and extracellular vehicles all contribute to the beneficial ef-fects of MSCs on tissue regeneration and repair. The paracrine substances secreted by MSCs change depending on the tissue microenvironment and biological behavior. In this review, we discuss the bioactive substances secreted by MSCs depending on the microenvironment and biological behavior and their regulatory mechanisms, which explain their potential to treat human diseases, to provide new ideas for further research and clinical cell-free therapy.& COPY; 2023 The Authors. Publishing services by Elsevier B.V. on behalf of KeAi Communications Co., Ltd. This is an open access article under the CC BY license (http://creativecommons.org/ licenses/by/4.0/).