Unveiling the phenotypic impact of cryopreservation on adipose derived stem cells: A systematic review

Background & objectives The impact of cell passaging and cryopreservation on the phenotypic and functional attributes of adipose-derived stem cells (ADSCs) must be understood to improve their clinical value. This systematic review investigates the phenotypic characteristics of ADSCs derived from fresh and cryopreserved adipose tissue, with a focus on how these cells change across passages. Methods A thorough search of databases was conducted as per the PRISMA guideline to find publications that were aligned with the inclusion criteria and were published between January 2013 and January 2023. Results In both cryopreserved and fresh stromal vascular fraction (SVF) cells, CD90, CD73, and CD105 consistently exhibited strong expression (90%) across passages in 50 screened studies. In fresh tissue, CD29 was upregulated in subsequent passages (up to 95%) but downregulated at passage 2 (2.3%). Variable CD29 was seen in cryopreserved groups (47% at P1, 90% at P4). While CD34 and CD45 were lower in cryopreserved ADSCs (less than 5%), they were higher in fresh tissue (41%), suggesting less haematopoietic contamination. Interpretation & conclusions Passaging and cryopreservation protocols can help maintain the therapeutic potential of ADSCs, providing a reliable source of functional stem cells for regenerative utilization.