Alginate as a cytocompatible carrier for mechanically isolated stromal vascular fraction: an in vitro proof-of-concept study.

Human adipose tissue-derived mechanically isolated stromal vascular fraction (mSVF) is a heterogeneous cell population containing mesenchymal stromal and progenitor cells known to have immense regenerative potential. Current research aims to enhance mSVF delivery by improving cell retention and survival, with hydrogels emerging as promising scaffolds. Among them, alginate stands out due to its biocompatibility, cost-effectiveness, and established use in wound healing and tissue engineering. In this study, mSVF was cultured in varying concentrations of alginate for 21 days and tested for hydrogel degradation, cell viability, as well as protein and growth factor release. Alginate encapsulated mSVF was co-cultured with human dermal fibroblasts and analyzed via immunohistochemical and immunofluorescence imaging. After 21 days, all hydrogel samples maintained their original size and shape regardless of alginate concentration. Cell viability and protein release were comparable to those of the positive control (mSVF only). In addition, the co-culture exhibited increased fibroblast viability as compared with negative controls as well as increased CD31 and CD73 expression. This in vitro proof-of-concept study demonstrates that alginate is a cytocompatible carrier for mSVF, maintaining cell survival and structural integrity over 21 days. Further in vivo validation is required before clinical translation. Our findings support its potential for enhancing cell-based therapies in regenerative medicine.