Glycosphingolipids of porcine, bovine, and equine pericardia as potential immune targets in bioprosthetic heart valve grafts.

BACKGROUND: Pericardial tissue from various animal species is utilized for the production of the bioprosthetic heart valves (BHV) used clinically. Experimental data show that the eventual breakdown of BHV is partly due to immunological interactions with carbohydrate tissue antigens. To understand these processes, we have examined the glycolipid-based carbohydrate antigens in naïve porcine, bovine, and equine pericardia. EXPERIMENTAL: Total non-acid and acid glycosphingolipid fractions were isolated from porcine, bovine, and equine pericardia, and individual glycolipid compounds were characterized by thin-layer chromatography, mass spectrometry, and binding of monoclonal antibodies, lectins and bacteria in chromatogram binding assays. RESULTS: The non-acid glycolipid fractions from all species contained glycosphingolipids based on the globo- and neolacto-series, including pentaglycosylceramides with terminal Galα3 determinants. Terminal blood group A and H (O) structures based on type 2 core chains were present in porcine pericardium, while the Forssman pentaosylceramide was found in equine pericardium. All acid glycolipid fractions contained sulfatide and several gangliosides with both N-acetyl- and N-glycolyl-neuraminic acid as terminal saccharide chain determinants. CONCLUSION: Several carbohydrate antigens which are potential targets for the human immune system have been identified in the animal pericardial tissues used for the production of BHV. Which of these antigens are left in the tissues after industrial BHV production processes, as well as their potential role in eventual BHV degradation, remains to be elucidated.

Onchocerca armillata contamination of a bovine pericardial xenograft in a human patient with repaired tetralogy of Fallot.

BACKGROUND: Bovine pericardial patches are used for many purposes, including facilitating right ventricular outflow tract reconstruction in patients with congenital heart disease. Here we present a case of parasitic contamination of a bovine pericardium used as a transannular patch during repair of tetralogy of Fallot 28 years prior at a hospital in China. METHODS: The patient presented to the University of Washington Medical Center for congestive heart failure and pulmonic regurgitation, and heart tissues including the xenograft pericardial patch were submitted to the Pathology Department and subsequently to the Comparative Pathology Program. RESULTS: The pericardial parasitic nodules with intralesional adult nematodes and microfilaria in the bovine tissues were preserved at harvest by (presumed) glutaraldehyde fixation. CONCLUSION: Onchocerca armillata parasitic pericardiopathy was diagnosed in the xenograft tissue based on the characteristic nematode morphology and the presumed geographic location of the donor bovine. This resulted in O. armillata contamination of the pericardial xenograft in a human patient with repaired tetralogy of Fallot.