EXPERIMENTAL Preserved Proliferative Capacity and Multipotency of Human Adipose-Derived Stem

Background: Human adipose-derived stem (stromal) cells are promising as a regenerative therapy tool for defective tissues of mesenchymal lineage, includ-ing fat, bone, and cartilage, and blood vessels. In potential future clinical applications, adipose-derived stem cell cryopreservation could be an indispens-able fundamental technology, as has occurred in other fields involving cell-based therapies using hematopoietic stem cells and umbilical cord blood cells. Methods: The authors examined the proliferative capacity and multipotency of human adipose-derived stem cells isolated from lipoaspirates of 18 patients in total before and after a 6-month cryopreservation following their defined pro-tocol. Proliferative capacity was quantified by measuring doubling time in cell culture, and multipotency was examined with differentiation assays for chon-drogenic, osteogenic, and adipogenic lineages. In addition, expression profiles of cell surface markers were determined by flow cytometry and compared between fresh and cryopreserved adipose-derived stem cells. Results: Cryopreserved adipose-derived stem cells fully retained the potentia