RECONSTITUTION OF BASEMENT-MEMBRANE AFTER SANDWICH TECHNIQUE SKIN-GRAFTING FOR SEVERE BURNS DEMONSTRATED BY IMMUNOHISTOCHEMISTRY

Reconstitution of basement membrane structures after ''sandwich-techni que'' grafting of severe deep burns is demonstrated with use of immuno histochemical techniques. Cryosections of human skin after epifascial burn wound excision and sandwich grafting were stained with monoclonal antibodies against type IV and VII collagen, polyvalent antiserum aga inst type VI collagen, and polyvalent antibody against laminin. Standa rd hematoxylin and eosin histologies were performed for morphologic co rrelation. Reorganization of the mesenchymal border zone (basement mem brane), after transplantation of extremely expanded split-thickness sk in autografts overlaid with glycerolized split-thickness skin allograf ts onto debrided human full-thickness wounds, occurred from day 5 to d ay 35. The autografts reepithelize the spaces between the mesh structu re, which has been covered primarily exclusively with allogenic skin, and form a layered squamous epithelium, with an underlying three-dimen sional basket-weave array of collagen in the remodeled neodermis after epifascial excision. Immunochemical techniques detect the reconstitut ion of a basement membrane zone with a typical architecture and distri bution of laminin, type IV, and type VII collagen being built up 1 wee k to 5 weeks after sandwich grafting. These structures can be seen in the autografts during the first 2 weeks and are consistent in the whol e reconstituted skin after day 35. To our knowledge this is the first report of the expression of type VI collagen in these types of wounds. The findings are compared with the expression of type VI collagen in healthy skin. The results indicate that the modified sandwich-grafting technique is an adequate means for early burn wound closure and resur facing of third-degree burn wounds and leads to the reconstitution of dermal qualities.