RESUMO
BACKGROUND: Naturally occurring human xenoreactive antibodies bind and agglutinate porcine RBCs. STUDY DESIGN AND METHODS: To determine if xenoantigen expression on RBCs of individual pigs of different breeds and blood groups is variable, and if it correlates with platelet (PLT) expression, we measured adsorption of affinity-purified antibodies to alpha-galactosyl (alphaGal) by RBCs or PLTs from 22 pigs representing four breeds. Hemagglutination of RBCs from these pigs was also performed with pools of human group OAB, A, B, and AB sera, as well as with anti-alphaGal-depleted pooled OAB human serum. RESULTS: There was significant variation in alphaGal expression on RBCs and PLTs among pigs. PLT alphaGal expression did not correlate with RBC alphaGal. RBCs from all pigs were agglutinated by pooled group O, AB, A, or B sera, whereas titers were reduced by 87 percent with anti-alphaGal-depleted serum and by 82 percent with AB sera from two volunteers. Agglutination titers were higher against RBCs from the five highest RBC alphaGal expressers compared with those from the five lowest RBC alphaGal expressers (92 +/- 12 vs. >160, p < 0.05, where 160 was the maximum dilution tested). CONCLUSION: Hemagglutination is a feasible alternative for rapid identification of pigs with RBCs carrying less alphaGal.