Mihić Anita Galić, Mayer Davor, Gradišar Katerina Jazbec, Maličev Elvira, Blagus Rok, Hrabač Pero, Alibegović Armin
Institute of Forensic Medicine and Criminalistics, School of Medicine, University of Zagreb, Šalata 11, Zagreb, 10000, Croatia.
Slovenian Institute for Transfusion Medicine, Šlajmerjeva 6, Ljubljana, 1000, Slovenia.
Int J Legal Med. 2025 Jul 16. doi: 10.1007/s00414-025-03549-4.
Determination of the postmortem interval (PMI) is one of the most challenging problems in forensic medicine. The main aim of this study was to determine the dynamics of the decrease in the fraction of viable chondrocytes excluded from the donors' knees for PMI determination. The other aim was to find an appropriate method for chondrocyte viability assay. We analyzed osteochondral cylinders from 35 donors (28 males and 7 females), aged 44 to 90 years, whose bodies were stored in refrigerators at temperature of 8 ± 2 °C, during the period from 4 to 83 days postmortem. The proportion of viable chondrocytes was determined by flow cytometry (FC) and cell viability analyzer (CVA). For FC we used RedDot™1 to mark all chondrocytes with nuclei (method FCN) and 7-AAD, to distinguish live/dead cells (method FCC) among RedDot™1 positive cells. Results revealed that chondrocytes from the knee cartilage can be found alive after more than two months postmortem. We observed that even in controlled temperatures and environment, the predicted interval for PMI is too wide for this method to be used in daily forensic practice, likely due to the relatively small number of donors considered in our study, and other unknown factors that affect the viability of chondrocytes in dead bodies. This could be verified with a larger number of donors followed over a longer period. FCC is a slightly superior method over CVA and FCN in terms of its ability for PMI determination.
死后间隔时间（PMI）的确定是法医学中最具挑战性的问题之一。本研究的主要目的是确定从供体膝关节获取用于PMI测定的存活软骨细胞比例的下降动态。另一个目的是找到一种合适的软骨细胞活力测定方法。我们分析了35名供体（28名男性和7名女性）的骨软骨柱，年龄在44至90岁之间，其尸体在死后4至83天期间保存在温度为8± 2°C的冰箱中。通过流式细胞术（FC）和细胞活力分析仪（CVA）测定存活软骨细胞的比例。对于FC，我们使用RedDot™1标记所有有核软骨细胞（方法FCN），并使用7-氨基放线菌素D（7-AAD）在RedDot™1阳性细胞中区分活/死细胞（方法FCC）。结果显示，死后两个多月仍可发现膝关节软骨中的软骨细胞存活。我们观察到，即使在可控的温度和环境下，PMI的预测间隔对于该方法在日常法医实践中的应用来说也太宽了，这可能是由于我们研究中考虑的供体数量相对较少，以及其他影响尸体中软骨细胞活力的未知因素所致。这一点可以通过对更多供体进行更长时间的跟踪来验证。就其测定PMI的能力而言，FCC方法略优于CVA和FCN方法。
