Molecular components, immune and stem cells in soft tissue regeneration

Wound healing is a spatiotemporal and highly regulated process that is divided into four continuous and overlapping stages: hemostasis, inflammation, repair (proliferation) and remodeling. All stages are controlled by various body systems and depend on the regulatory role of immune and stem cells. Despite significant progress in understanding the cellular and molecular mechanisms of inflammation, the role of the immune microenvironment in the regeneration process remains unclear. On the one hand, the critical importance of the cellular and molecular components of the immune system in the reparative response of tissues, including the degree of scarring, restoration of structure and function of organs, has been proven, and on the other hand, little data is presented on the loss of tissue regeneration ability associated with the immune competence evolution. The review presents the key cellular and molecular mechanisms of the immune response and of the stem cells participation soft tissue repair process during their interaction with the extracellular matrix. An analysis of the latest scientific data on the participation of components of the immune microenvironment and of stem cells in soft tissue repair process was carried out based on the publications presented in Google Scholar, Medline, PubMed, Scopus and Web of Science. It has been shown that the nature of this response and its duration have a significant impact on the outcome of repair – from incomplete recovery (scarring or fibrosis) to full regeneration. It is indicated that various types of immune and stem cells take part in the soft tissue repair and remodeling processes, and their interaction must be precisely controlled. The review data may provide the basis for the development of new therapeutic approaches for soft tissue repair through immune regulation or the use of stem cells and extracellular vesicles.