Journal of the American Heart Association: Cardiovascular and Cerebrovascular Disease (May 2016)

Ribonuclease (RNase) Prolongs Survival of Grafts in Experimental Heart Transplantation

  • Eike Kleinert,
  • Martin C. Langenmayer,
  • Bruno Reichart,
  • Jana Kindermann,
  • Barbara Griemert,
  • Andreas Blutke,
  • Kerstin Troidl,
  • Tanja Mayr,
  • Tobias Grantzow,
  • Fatih Noyan,
  • Jan‐Michael Abicht,
  • Silvia Fischer,
  • Klaus T. Preissner,
  • Ruediger Wanke,
  • Elisabeth Deindl,
  • Sonja Guethoff

DOI
https://doi.org/10.1161/JAHA.116.003429
Journal volume & issue
Vol. 5, no. 5

Abstract

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BackgroundCell damage, tissue and vascular injury are associated with the exposure and release of intracellular components such as RNA, which promote inflammatory reactions and thrombosis. Based on the counteracting anti‐inflammatory and cardioprotective functions of ribonuclease A (RNase A) in this context, its role in an experimental model of heart transplantation in rats was studied. Methods and ResultsInbred BN/OrlRj rat cardiac allografts were heterotopically transplanted into inbred LEW/OrlRj rats. Recipients were intravenously treated every other day with saline or bovine pancreatic RNase A (50 μg/kg). Toxic side effects were not found (macroscopically and histologically). Heart tissue flow cytometry and quantitative morphological analyses of explanted hearts at postoperative day 1 or postoperative day 4 showed reduced leukocyte infiltration, edema, and thrombus formation in RNase A‐treated rats. In allogeneic mixed lymphocyte reactions, RNase A decreased the proliferation of effector T cells. RNase A treatment of rats resulted in prolonged median graft survival up to 10.5 days (interquartile range 1.8) compared to 6.5 days (interquartile range 1.0) in saline treatment (P=0.001). Treatment of rats with a new generated (recombinant) human pancreatic RNase 1 prolonged median graft survival similarly, unlike treatment with (recombinant) inactive human RNase 1 (each 50 μg/kg IV every other day, 11.0 days, interquartile range 0.3, versus 8.0 days, interquartile range 0.5, P=0.007). ConclusionsUpon heart transplantation, RNase administration appears to present a promising and safe drug to counteract ischemia/reperfusion injury and graft rejection. Furthermore, RNase treatment may be considered in situations of critical reperfusion after percutaneous coronary interventions or in cardiac surgery using the heart–lung machine.

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