Active wound dressing with artificial capillaries for temporary wound irrigation and skin cell supply.

Medical treatment of burns and chronic wounds remains a challenge. We discussed a therapy concept that combines skin cell spray transplantation with a novel wound dressing based on artificial hollow fiber membrane capillaries. In skin cell-based therapy development, autologous skin progenitor cells are isolated from a healthy skin area and sprayed onto the wound. A medical device was introduced that uses perfused capillaries, known from clinical plasma separation, as a temporarily applied extracorporeal wound capillary bed. The functions of the dressing are comparable with those of dialysis; the capillaries, however, are applied externally onto the wound. Perfusion with a clinical peripheral nutrition and buffer solution can provide wound irrigation, wound debris removal, cell nutrition, pH regulation, and electrolyte balance while potentially serving to address delivery of regenerative factors and antibiosis. An innovative active skin wound dressing that provides cell support and stimulates regeneration by wound irrigation is discussed.

Feasibility study of an active wound dressing based on hollow fiber membranes in a porcine wound model.

INVESTIGATION: A novel active wound dressing (AWD) concept based on a microporous hollow fiber membrane network was investigated in an animal model. It provides a local solution-perfused environment for regenerative cell nutrition, wound irrigation, debris removal, electrolyte balancing, pH regulation, and topical antibiosis. The device is capable of supplying soluble factors, as tested experimentally for the recombinant human growth and differentiation factor-5 (rhGDF-5). METHODS: Following in vitro studies for rhGDF-5 using primary human keratinocytes and dermal fibroblasts, we employed a porcine partial thickness wound model with five distinct wounds on each back of n=8 pigs. Four wound groups were perfused differently over 9 days and compared with a negative control wound without perfusion: (1) 1% trehalose solution, pH 5.5; (2) rhGDF-5 (150 ng/ml) in 1% trehalose solution, pH 5.5; (3) nutrition solution; and (4) rhGDF-5 (150 ng/ml) in nutrition solution with 1% trehalose, pH 5.5. RESULTS: Promoted wound healing was observed within group 1 and more pronounced within group 2. Groups 3 and 4, with nutrition solution, showed significant adverse effects on wound healing (p<0.05). CONCLUSIONS: The investigated AWD concept appears to be an interesting therapeutic tool to study further wound healing support. Additionally, topical application of rhGDF-5 could be promising.