Alpha-1-Antitrypsin Treatment Prevents Hepatic Ischemia-Reperfusion Injury in Mice.

Abstract

Warm ischemia associated with non-heart beating donation negatively affects early graft function and long-term survival. Recent evidence shows that treatment with acute phase protein alpha-1-antitrypsine (A1AT) reduces cell death and inflammation in a kidney ischemia-reperfusion injury (IRI) model. For liver, protective effects of A1AT on IRI are unknown. We investigated if A1AT treatment protects against hepatic injury in vitro and in a mouse model of hepatic IRI. Methods The effect of human A1AT (Zemaira, CSL Behring, 2.5 mg/ml) on cell viability was tested on Huh7 cells (MTT assay). Both normothermic (37 °C) and hypothermic conditions (18h 4 °C medium or UW solution followed by 24h medium 37 °C) were tested. The effect of A1AT on hepatic IRI was tested in C57BL6 mice, subjected to partial hepatic warm ischemia for 75 min by clamping the left hepatic artery and vein. Mice were either sham operated without induction of hepatic IRI (n=3), or IV injected with PBS n=7) or 10 mg/kg A1AT (n=5) 10 min prior to IRI. Serum at 6 and 24h after IRI was tested for AST, ALT and LDH Results Huh7 viability was increased for A1AT treated cells (1.3x ctrl, p=0.009). Increased viability was even more pronounced after cooling and rewarming with both medium (1.8x ctrl, p=0.006) or UW (1.9x, p=0.019). In vivo, compared to sham operated mice, levels of AST, ALT and LDH were all significantly increased at 6 and 24h after warm hepatic IRI but less in A1AT mice (p≤0.05). In mice treated with A1AT the protective effects were most apparent 24h after IRI, with significant reduction in ALT (mean±SEM 4235±699 U/L vs. 1506±542.4) and LDH (9890±2476 vs. 460±378 U/L) (p<0.05). At peak of injury 6h after IRI, only ALT was significantly reduced (13583±1267 U/L PBS vs. 7620±1829 A1AT, p=0.042). Conclusion Treatment with A1AT shows protective effects in Huh7 cells and attenuates hepatic IRI in mice. This result warrants further research on using A1AT for preemptive treatment of donors during organ procurement or liver graft cold storage. (research support from CSL Behring)Figure: No Caption available.DISCLOSURES:Berger, M.: Employee, CSL Behring.