Antibody formation towards porcine tissue in patients implanted with crosslinked heart valves is directed to antigenic tissue proteins and αGal epitopes and is reduced in healthy vegetarian subjects

Background Glutaraldehyde‐fixed porcine heart valves (ga‐pV) are one of the most frequently used substitutes for insufficient aortic and pulmonary heart valves which, however, degenerate after 10‐15 years. Yet, xeno‐immunogenicity of ga‐pV in humans including identification of immunogens still needs to be investigated. We here determined the immunogenicity of ga‐pV in patients with respect to antibody formation, identity of immunogens and potential options to reduce antibody levels. Methods Levels of tissue‐specific and anti‐αGal antibodies were determined retrospectively in patients who received ga‐pV for 51 months (n=4), 25 months (n=6) or 5 months (n=4) and compared to age‐matched untreated subjects (n=10) or younger subjects with or without vegetarian diet (n=12/15). Immunogenic proteins were investigated by Western blot approaches. Results Tissue‐specific antibodies in patients were elevated after 5 (1.73‐fold) and 25 (1.46‐fold, both P