Combination of clopidogrel and everolimus dramatically reduced the development of transplant arteriosclerosis in murine aortic allografts

Abstract

Summary Our group has shown that platelet inhibition with clopidogrel, an antagonist of the P2Y12 adenosine diphosphate receptor on platelets, reduced the formation of transplant arteriosclerosis. The aim of this study was to investigate whether a combination of cyclosporin or everolimus with clopidogrel has a beneficial effect on the development of transplant arteriosclerosis. Fully MHC mismatched C57Bl/6 (H2b) donor aortas were transplanted into CBA.J (H2k) recipients and mice received either clopidogrel alone (1 mg/kg/day) or in combination with cyclosporin (2 mg/kg/day) or everolimus (0.05 mg/kg/day). Grafts were analysed by histology and morphometry on day 30 after transplantation. In mice treated with clopidogrel alone, transplant arteriosclerosis was significantly reduced [intima proliferation 56 ± 11% vs. 81 ± 7% (control)/n = 7]. Daily application of everolimus reduced the development of transplant arteriosclerosis compared with untreated controls [intima proliferation of 29 ± 9% vs. 81 ± 7% (control)/n = 7]. Strikingly, combination of clopidogrel and everolimus almost abolished the formation of transplant arteriosclerosis [intima proliferation: 11 ± 8% vs. 81 ± 7% (control)/n = 7]. By contrast, combination of cyclosporin and clopidogrel compared with clopidogrel alone showed no additive effect. These results demonstrate that combination of platelet‐ and mammalian target of Rapamycin‐inhibition can dramatically reduce the development of transplant arteriosclerosis.

Adenosine Diphosphate Receptor P2Y12-Mediated Migration of Host Smooth Muscle-Like Cells and Leukocytes in the Development of Transplant Arteriosclerosis

“…In the present experiments, the cells harvested from KO mice showed a significant reduction of migration stimulated by ADP or 2MeSADP in vitro, and diminished accumulation in the transplanted arteries in vivo. This observation is in part supported by recent reports describing that clopidogrel, a P2Y 12 receptor antagonist, reduces transendothelial migration of dendritic cells and microphages within the vessel wall of murine aortic allografts (17,18). Thus, our findings in the present study provide further evidence that, in addition to platelet P2Y 12 receptor-mediated TA progression (13,14), P2Y 12 receptors on other cell types also substantially contribute to the development of TA.…”

Functional, morphologic, and molecular characterization of cold storage injury

“…19 Murine models of vessel transplantation studies usually use the thoracic aorta. 20 The present study characterizes cold storage injury of mouse aorta on functional and molecular levels.…”

Clopidogrel significantly lowers the development of atherosclerosis in ApoE-deficient mice in vivo

“…In human studies, the P2Y 12 receptor inhibitor clopidogrel showed anti-inflammatory properties aside its known role as anti-thrombotic agent [7,8]. Furthermore previous studies showed the immunological influence of clopidogrel on the reduction of transplant arteriosclerosis in a fully allogeneic murine aortic allograft model via modulation of adhesion molecule and cytokine expression associated with reduced infiltration of DCs and macrophages within the vascular wall [9][10][11]. ApoE −/− mice develop atherosclerotic lesions faster than wild-type mice when fed a high-cholesterol diet and therefore represent an ideal model to investigate platelet adhesion in the development of atherosclerosis [12].…”