Other Non-α1,3Gal Antigens

Since understanding of the impact in xenoantigenic determinant Galα1,3Gal-R and anti-α1,3Gal Abs during xenoantigenic damages and injuries, other non-α1,3Gal glycan xenoantigens, the non-α1,3Gal epitope-reactive immune responses, and their related inflammation reactions have not well been explained. The α1,3Gal-T enzyme required for the biosynthesis of α1,3Gal-carrying antigenic epitopes [1] and α1,3Gal glycan-terminating GSLs is also discovered from bovine cells. Barone et al. [2] found and elucidated both structures of non-acidic neutral GSLs and acidic GSLs from pulmonary and aortic endothelium of naïve pig aortic vessel using α1,3Gal-specific Griffonia simplicifolia IB4 lectin, GS-IB4. To characterize the antibody reactivity of patient tissues with bioprosthetic valves of pig valves, acidic GSLs and non-acidic neural GSLs were isolated from pulmonary and aortic cusps of pig valves. The isolated GSLs have been analyzed for their characterization by MS analysis and recognition properties and patterns of glycan-binding ligands. The non-acidic neutral GSLs have been specified as globotetraosyl-Ceramide, H-type 2 pentaosyl-ceramide, Fuc-gangliotetraosyl-Ceramide, and Galα1,3neolactotetraosyl-Ceramide. The acidic GSLs contained gangliosides including GM1, GM2, GM3, Fuc-GM1, GD1a and GD3, and sulfatides. All gangliosides consisted of NeuAc residues. Significantly, the main component, NeuGc of NeuAc variant, was present in various organs of pig. To humans, it can induce development of Abs. Such glycan structures bound with complex lipids in pigs can possibly be target candidates for the immune system of human.