Forensic application of CAMP expression for the determination of wound vitality in human compressed neck skin

Determining whether ligature marks represent antemortem or postmortem injuries is a critical issue in forensic practice because this distinction directly influences the reconstruction of perimortem events. Consequently, assessing the vital reaction of neck skin plays an essential role in evaluating the viability of compression-related injuries. Cathelicidin antimicrobial peptide (CAMP), a multifunctional host-defense peptide involved in inflammation, immune cell recruitment, and wound repair, may serve as a reliable molecular marker for wound vitality. In this study, we examined CAMP expression in 40 ligature mark samples (32 samples of hanging and 8 samples of ligature/manual strangulation) obtained during forensic autopsies, along with matched intact skin controls, all with postmortem intervals of ≤ 3 days. Immunohistochemistry revealed strong CAMP expression in epidermal keratinocytes and moderate expression in dermal cells at compression sites, whereas control skin showed only faint or absent staining. Morphometric analysis demonstrated that the ratio of CAMP‑positive keratinocytes and the number of CAMP-positive dermal cells were significantly higher in compressed skin than in controls, independent of age, sex or postmortem interval. Moreover, neither ligature type nor mode of neck compression also had no influence on CAMP expression in the keratinocytes or dermal cells. These findings indicate that CAMP expression reflects a biological response to antemortem neck compression and may provide an objective molecular marker for assessing wound vitality in forensic pathology. Furthermore, combining CAMP with other established biomarkers may enhance diagnostic reliability when evaluating antemortem neck compression injuries.