Immunohistochemical localization of Langerhans cells as a tool for vitality in hanging mark wounds: a pilot study

Hanging deaths are common and characterized by their brief survival time. Macroscopic and histological exams are frequently unable to distinguish vital lesions from post-mortem lesions. This pilot study investigates the dendritic and mast cells in hanging marks to establish vitality lesions. Skin specimens were taken from vital wounds, ligature marks, and post-mortem lesions. Cryosections were stained for haematoxylin eosin, avidin, CD1a and MHC class II+ antigens and examined under light or fluorescence microscopies. Using digitized photomicrographs the images were then analysed. Differences were found in the Langerhans cells and epidermal MHC density, the vital lesions and ligature marks and the other specimens. The results may prove useful in forensic practice when neither macro nor microscopic objective evidence of vitality is available. The results could very possibly support the hypothesis that the amount of time it takes to die from hanging is less than currently believed (< 5 min).