Abstract
Mesenchymal stromal cells (MSCs) are multipotent cells characterized by their regenerative capacity and strong immunomodulatory properties. In recent years, MSC-based therapy has attracted significant attention as a potential treatment for a wide range of immune-mediated and degenerative diseases. The therapeutic effects of MSCs are primarily mediated through paracrine signaling and secretion of cytokines that regulate immune responses and promote tissue repair. This review focuses on five key cytokines involved in MSC immunomodulation: interleukin-6 (IL-6), interleukin-10 (IL-10), transforming growth factor-beta (TGF-β), tumor necrosis factor-alpha (TNF-α), and interleukin-1 beta (IL-1β). These cytokines interact within a complex signaling network that allows MSCs to suppress excessive inflammation and restore immune balance. The role of MSC therapy is examined in several clinically relevant conditions, including systemic lupus erythematosus, systemic sclerosis, ischemic stroke, spinal cord injury, diabetes mellitus, and female infertility. Across these diseases, MSCs demonstrate the ability to inhibit pro-inflammatory immune cell activity, promote regulatory immune phenotypes, reduce oxidative stress, and stimulate regeneration through the secretion of growth factors and extracellular vesicles. Despite promising experimental and early clinical findings, several limitations remain, including variability in MSC sources, limited cell survival after transplantation, and the need for optimized dosing strategies. Overall, MSC therapy represents a multifunctional therapeutic approach combining immunomodulation, anti-inflammatory activity, and regenerative support. Further research is required to better understand cytokine interactions, improve standardization of MSC-based treatments, and enhance clinical efficacy across diverse pathological conditions.