INFLUENCE OF POSTMORTEM CHANGES ON IMMUNOHISTOCHEMICAL REACTIONS IN SKIN

The influence of postmortem damage of tissues on the immunohistochemic al diagnosis of wound age has not as yet been clarified. We utilized a ntibodies against the proteinase inhibitors alpha-1-antichymotrypsin a nd alpha-2-macroglobulin, fibronectin and lysozyme to study samples of skin which had been intact intravitally, but were damaged postmortem either by autolysis or compression with a surgical clamp at the time o f dissection. Even in the absence of autolysis, antibodies against the proteinase inhibitors and fibronectin exhibited staining of tissue ma rgins. Autolysis caused an increase in false positive results. In cont rast, antibodies against lysozyme did not give false positive staining . There were no antigens sensitive to postmortem clamping and false po sitive results were not observed, Antibodies against proteinase inhibi tors are not useful for the diagnosis of wound age because of a high n umber of false positive reactions in marginal areas. Fibronectin also showed false positive band-shaped staining patterns at the tissue marg in. In addition, autolytic processes increase the number of false posi tives. The antibody against lysozyme is much less sensitive to autolys is and no false positive reactions were observed in our series of test s.