gms | German Medical Science

Background: Adipose tissue contains a large number of multipotent cells, which is a prerequisite for stem-cell-based therapies. A combination of this cell-based therapy with suitable commercial clinically used matrices, such as the collagen and elastin scaffolds (Matriderm™), can be promising for soft tissue reconstruction. Our previous work showed that the method of liposuction can influence the viability of the obtained isolated cells from adipose tissue and also the quantity of growth factors. Nevertheless, in order to simulate an intra-operative situation, isolation of adipose-derived stromal vascular fraction cells shall take place directly after each fat harvesting procedure and transplantation of these isolated cells has to be performed immediately to the Matriderm™ construct.

Methods: Liposuction procedures (fat harvesting) were performed electively for 10 healthy patients. After each fat harvesting procedure, isolation of adipose-derived stromal cells took place directly followed by transplantation to selected scaffolds (Matriderm™). Vitality test has been performed with alamarBlueTM assay in different time intervals after transplantation of cells onto Matriderm sheets (1 h, 3 h, 24 hours, 3 days, 7 days and 13 days after transplantation). Histological analysis and morphological assessments for the enriched matrices were performed under two-photon microscopy, which was supported by second harmonic generation. In addition, different mediums have been added to the enriched scaffolds, including 9% NaCL, PBS, DMEM and FCS/bFGF loaded DMEM, in order to investigate the affect of injected solutions on cellular viability on Matriderm™ during the proliferation and adipogenic conversion face.

Results: The viability and adherence rate of isolated adipose-derived cells onto collagen elastin matrices was almost the double in just 3 hours when compared to those results obtained in one hour after transplantation on the same scaffolds indicating that more incubation time on the scaffolds will result in more adherence rate in different levels through the 3D structure of the enriched matrices with isolated adipose derived stromal vascular fraction cells, which was also supported by histological analysis and two-photon microscopy showing viable cytoplasm and nuclei. However, Cells enriched with 9% NaCL on Matriderm™ were found to have the low viability rate if compared to those results with PBS enriched cells on Matriderm™.

Conclusion: Fresh isolated adipose-derived stromal cells can be transplanted safely onto Matriderm™ matrices in a short time without time demanding cell culture steps or further expansion. This study suggests that in the time interval of a surgical procedure, i.e. treatment of burn patients and different types of wounds debridement, dermal biocompatible scaffolds such as Matriderm™ can be enriched successfully with potentially regenerative adipose-derived stromal vascular fraction cells. Nevertheless, it is necessary to optimise this approach for clinical uses with safe and compatible materials.