Immunogenicity of glycerol-preserved human cadaver skin in vitro

Donor allograft skin preserved in 85% glycerol is used as a temporary coverage for large burn wounds. Glycerol treatment does not affect the structural integrity of the skin; cells are well preserved but dead. However, cells expressing major histocompatibility class II molecules can still be observed. In this study we investigated the mechanism underlying the clinical observation that glycerol-treated alloskin will be destroyed but after a prolonged period. We compared the in vitro immunogenicity of untreated and 85% glycerol-treated human skin cells. Human purified blood T cells did not proliferate when cultured with allogeneic treated skin cells, whereas untreated cells induced a distinct response. A moderate response was measured after adding T cells and viable antigen presenting cells, such as monocytes, to the allogeneic treated skin cells. However, the response on untreated skin cells was much higher. These results favor the suggestion that after transplantation of glycerol preserved skin is performed, an inflammatory process mediated by infiltrating host monocytes occurs rather than a rejection process mediated by T cells.