Isolation and characterization of human multilineage-differentiating stress-enduring cells for use in tissue engineering: a systematic review.

Human multilineage-differentiating stress-enduring (MUSE) cells represent a promising cell population for tissue engineering and translational medicine owing to their intrinsic pluripotency and stress resistance. MUSE cells express pluripotency markers such as SSEA-3, Nanog, Sox2, and Oct3/4, while maintaining their immunomodulatory capabilities. This systematic review (PROSPERO CRD42024532621) analyzed studies on human MUSE cell isolation, characterization, and translational potential through searches of the PubMed, Scopus, and Web of Science databases in April 2024. The TIDieR and SYRCLE checklists were used to assess the risk of bias. Our findings identified 34 studies that followed the PRISMA guidelines for assessing different tissue sources, isolation techniques, and characterization methods. MUSE cells are primarily obtained from bone marrow mesenchymal stem cells, and fluorescence-activated cell sorting is the predominant isolation method. Characterization was mainly performed using SSEA-3 immunodetection (positivity ranged from <1% to 6.30%) and was linked to the expression of pluripotency and mesenchymal markers. These findings highlight the relevance of MUSE cells in regenerative medicine as a distinct pluripotent subpopulation within adult mesenchymal tissues. In addition, SSEA-3-based isolation approaches complemented by functional assays has emerged as a key methodological approach for the reliable identification and characterization of MUSE cells. However, isolation efficiency varies depending on the cell source and method. Standardized protocols are, therefore, needed to improve reproducibility and facilitate the translational development of MUSE cell-based regenerative therapies.