Alginate as a carrier for mechanically isolated Stromal Vascular Fraction

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 of different concentrations maintained the original size and shape. Cell viability and protein release was comparable to the positive control of mSVF only. Fibroblast growth factor (FGF) release, as quantified by growth factor analysis, increased in the co-culture. In addition, the co-culture exhibited increased fibroblast viability as compared with negative controls as well as increased CD31 and CD73 expression. As a long-term proof-of-concept, we demonstrate alginate is an attractive carrier for mSVF. Our findings support its potential for enhancing cell-based therapies in regenerative medicine.