Immunohistochemical Expression of GFAP in the Brain Astrocytes of Deceased Newborns Depending on the Postmortem Interval.

Abstract

The changes in astrocytes and their role in the development of brain diseases can be identified by morphological analysis of tissue specimens, in particular, by immunohistochemical detection of glial fibrillary acidic protein (GFAP). The study presents analysis of GFAP expression in white matter astrocytes of deceased newborns depending on the duration of the postmortem period. Autopsy material of the brain tissue obtained from 48 deceased newborns was divided into 8 groups depending on the duration of the postmortem period. Immunohistochemical analysis was performed with antibodies to GFAP in tissue samples taken from the superior and inferior brain areas relative to the position of the body stored before autopsy. The area of GFAP+ staining per field of view was determined in the white matter using an image analysis system. Morphometric analysis revealed a decrease in the mean values of the area of GFAP+ staining, i.e. the number of fibrotic astrocytes and their processes decreased with increasing the duration of the postmortem period. The mean areas of GFAP+ staining in the superior and inferior areas of the white matter did not differ significantly between the groups. The identified changes reflect the development of nonspecific postmortem changes which should be considered when taking tissue samples for molecular biological studies and in differential forensic diagnosis with lifetime lesions and diseases.