Human ABO blood group is important in survival and function of porcine working hearts

Pig organs express alphaGal antigen and thus are hyperacutely rejected if perfused by human blood. Human B/A antigens are similar to pig alphaGal antigen, suggesting that the corresponding antibodies may cross-react. Our purpose was to determine if there is a human ABO blood-group difference in porcine-human xenotransplantation. Plasma from six A, five B, seven AB, and six O individuals pooled by blood group were tested in an ex-vivo porcine working heart model. Blood-group A plasma-perfused hearts survived 20 +/- 14 min (n = 5), B 241 +/- 9 min (n = 3), AB 151 +/- 37 min (n = 5), and O 9 +/- 1 min (n = 8). A and O were different (p < 0.001) from B and AB. Function was significantly better in group B. Edema accumulation and creatine kinase change was highest in A and O. All groups had comparable levels of anti-alphaGal antibody, as well as comparable perfusion and operative conditions. Multivariate linear regression analysis showed the anti-B antibody levels to be predictive of survival (p < 0.001). At higher plasma concentrations, hearts perfused with B plasma survived longer (p = 0.01) than AB (218 +/- 45 min, n = 4 vs. 6 +/- 0 min, n = 3). These results suggest a human ABO blood-group difference in porcine-to-human xenotransplantation, which may be mediated by the anti-A and anti-B antibodies.