Open AccessExpression of human thrombomodulin on porcine endothelial cells can reduce platelet aggregation but did not reduce activation of complement or endothelium – an experimental study
Author(s) -
Ramackers Wolf,
Rataj Dennis,
Werwitzke Sonja,
Bergmann Sabine,
Winkler Michael,
Wünsch Annegret,
Bähr Andrea,
Wolf Eckard,
Klymiuk Nikolai,
Ayares David,
Tiede Andreas
Publication year - 2020
Publication title -
transplant international
Language(s) - English
Resource type - Journals
SCImago Journal Rank - 0.998
H-Index - 82
eISSN - 1432-2277
pISSN - 0934-0874
DOI - 10.1111/tri.13573
Subject(s) - thrombomodulin , medicine , platelet , endothelium , complement system , complement (music) , immunology , platelet aggregation , platelet activation , microbiology and biotechnology , thrombin , biochemistry , immune system , biology , gene , complementation , phenotype
Summary Clinical xenotransplantation will only be feasible when present limitations can be controlled sufficiently. Activation of endothelium and complement as well as coagulopathy and thrombotic microangiopathy (TMA) is important barriers. Transgenic expression of hTBM on porcine endothelial cells is a reasonable approach to reduce activation of haemostasis. Endothelial cells from wild‐type pigs as well from pigs expressing hTBM alone or in combination with hCD46 and knockout of the alpha‐1,3,‐galactosyltransferase (GTKO) were perfused with platelet‐rich plasma in a microfluidic flow chamber. Platelet aggregation and activation, coagulation, complement and endothelial cell activation were assessed. Perfusion of wild‐type porcine aortic endothelial cells (PAEC) resulted in distinct platelet aggregation. Expression of hTBM in either mono‐transgenic or triple‐transgenic (GTKO/hCD46/hTBM) PAEC showed significantly reduced or absent platelet aggregation. Flow cytometric analysis of platelets showed an increased CD62P expression in wild‐type PAEC and significantly reduced expression in mono‐ or triple‐transgenic PAEC. Activation of coagulation measured by TAT occured in WT PAEC and was clearly reduced in hTBM and GTKO/hCD46/hTBM PAEC. Activation of complement and endothelial cells was only reduced in GTKO/hCD46/hTBM but not in PAEC expressing hTBM alone. Expression of hTBM was able to prevent activation of coagulation and platelet aggregation in mono‐ and triple‐transgenic PAEC, while activation of complement and endothelial cells was not reduced in mono‐transgenic PAEC.