Presentation mode of glycans affect recognition of human serum anti-Neu5Gc IgG antibodies

Recognition of carbohydrates by antibodies can be affected by antigen composition and density. This had been investigated in a variety of controllable multivalent systems using synthetic carbohydrate antigens, yet such effects on anti-carbohydrate antibodies in circulating human serum have not been fully addressed thus far. All humans develop a polyclonal and diverse response against carbohydrates containing a non-human sialic acid form, N-glycolylneuraminic acid (Neu5Gc). This red meat-derived monosaccharide is incorporated into a diverse collection of human glycans resulting in circulating anti-Neu5Gc antibodies in human sera. Such antibodies can cause exacerbation of diseases mediated by chronic inflammation such as cancer and atherosclerosis. We aimed to evaluate how different presentation modes of Neu5Gc-glycans can affect the detection of anti-Neu5Gc IgGs in human serum. Here, we compare serum IgG recognition of Neu5Gc-containing glycoproteins, glycopeptides and synthetic glycans. First, Neu5Gc-posi...