Adipose Stem Cells Laden Oxidized Alginate Hydrogels As Injectable Anti-Aging Biofiller

Goals/Purpose:

  Autologous fat transplantation is frequently used as filler in the cosmetic and reconstructive plastic surgery for volume restoration in the variety of contour defect. And recent studies have demonstrated the ability of adipose derived stem cells (ADSCs) to stimulate collagen synthesis at the recipient site that provides a fuller dermis and provides a more youthful appearance in subjects. The utility of a local protective milieu, such as an encasing hydrogel, could enhance the biological efficacy of injected cells. The aim of this experiment was to investigate this mechanism using a alginate hydrogel system with human adipose derived stem cells(hADSCs).

Methods/Technique:

  Degradation properties of Alginate hydrogels were tuned by partial periodate oxidation of the polymer chains and used to encapsulate hADSCs that were injected subcutaneously in the dorsum of nude mice(n=12). The contralateral side received hydrogel alone as a control. After 12 weeks, the two sites were dissected and evaluated by histology with special stains namely, HE, Masson Trichrome, Picrosirus Red F3B with polarizing microscopy, Van Gieson and Alcian Blue staining. To investigate the origin of host versus graft cells and collagen deposition, immunostaing for human type I/III collagen, mouse type I collagen and mouse SRY were performed. At 4 weeks, protein array of lysates were performed to identify the upregulated cytokines.

Results/Complications:

  On gross examination, newly generated tissues appeared whitish and soft in experimental group. Dermal thickness of skin overlying implant was significantly increased, compared with control group. Histologic examination of the implants showed abundant extracellular matrix in the injected hADSCs with gel as evidenced by histological examination. Increased collagen fibers in the dermis were observed to be of mouse origin probably as a result of hADSC secreted factors stimulating host fibroblasts. 

Conclusion:

  This study shows that the potential of hADSCs-hydrogel implants as a biofiller stimulating a synthesis of collagen fiber at the recipient site and making the dermis thicker, inducing anti-aging effect. However, long-term effects need further investigation.