Apoptosis, Not Necrosis, during Ex-Vivo Lung Perfusion Is Correlated with Severe PGD

Abstract

Purpose We hypothesized that a donor lung which develops more apoptosis during ex-vivo lung perfusion (EVLP) tends to experience severer primary graft dysfunction (PGD) after transplant and that cell death markers in perfusate can be used for prediction of subsequent PGD3. Methods and Materials This is a single-institution retrospective case-control study. A correlation of the outcome of recipients after EVLP and cell death markers in EVLP perfusate was investigated. From 2008 to 2012, 77 high-risk donor lungs were subjected to normothermic acellular EVLP for 4 to 6 hours. Lungs were judged for transplantation based on physiological assessment. The cases (PGD group, N=8) were patients who developed PGD 3 within 72h after lung transplant. The matched controls (Control group, N=8) were selected from patients who had PGD 0, 1 or 2 within 72 h after transplant. Matching factors were recipient age, gender and lung disease. A matched design was used to minimize biases of recipient factors affecting the outcome. Cell death markers including M30, M65 and HMGB-1 were measured with ELISA in perfusate at 1h and the end of EVLP. Results M30 which indicates epithelial apoptosis didn’t show a significant difference between two groups in perfusate at 1h. However, M30 in PGD group was significantly higher compared to Control group at the end of EVLP (p=0.015). M30 at the end of EVLP increased significantly compared to 1 h (p=0.016). M65 which indicates epithelial apoptosis and necrosis didn’t show a significant difference between two groups in both time-points. HMGB-1, which is a mediator of inflammation / immune response and released from dead cells, was significantly higher in PGD group at the end (p=0.035) but not at 1h of EVLP. Using ROC curve, AUC of M30 at the end of EVLP was 0.84 (95%CI: 0.62-1.06, p=0.035) and AUC of HMGB-1 at the end of EVLP was 0.85 (95%CI: 0.64-1.06, p=0.029). Conclusions Epithelial cell apoptosis is related to subsequent PGD3, but necrosis didn’t correlate with PGD severity. M30 and HMGB-1 are predictive perfusate markers for PGD3.