Two-tailed delimitation of the time of death by immunohistochemical detection of somatostatin and GFAP

Abstract

Delimitating the time of death becomes increasingly difficult and inaccurate, the further back it lays in time. To contribute to available techniques, pancreas and brain tissue from 500 corpses, whose time of death lay within 1 day and 23 days ±1 day, were immunohistochemically stained with anti-somatostatin and anti-glial fibrillary acidic protein (GFAP) antibodies. Somatostatin and GFAP are recognized as antigen by the employed antibodies. This does not occur when proteolytic processes after death disturb the tertiary structure, altering its antigen properties. In our cases, stainability of somatostatin in the pancreas was always given within 2 days after death. Hence, given a negative immunoreaction, death can be assumed to have occurred a minimum of 3 days before formaldehyde fixation, which stops the proteolysis. A negative immunoreaction occurred consistently after 11 days, indicating that if a positive reaction is obtained in a specimen, the death of the respective person must have occurred amaximum of 10 days before fixation. GFAP was always stainable in the frontal cortex within 3 days after death, which means that in the case of a negative immunoreaction, death can be assumed to have occurred a minimum of 4 days before fixation. A negative immunoreaction occurred consistently after 14 days, indicating that if a positive reaction is obtained in a specimen the death of the respective person must have occurred a maximum of 13 days before fixation. The presented methods provide further improvements of the possibilities of delimitating the time of death, whereby the combination of both methods allows a two-tailed delimitation.