| Summary: | A method for the purification of human serum immunoglobulin Al (IgA1), suitable for subsequent oligosaccharide analysis, was devised. The N- and 0-linked glycans of normal human serum IgA1 were released from the protein and the structures determined by a combination of gas-chromatography mass spectrometry, nuclear magnetic resonance spectroscopy and enzymatic degradation. The glycans from serum IgA1 from normal humans and patients with rheumatoid arthritis were compared. Contrary to observations for immunoglobulin G (IgG), no significant alterations in the IgA1 glycans were encountered in the disease state, suggesting that the defect is IgG specific. The antibodies HNK-1 and L2 bind to a number of glycoproteins important in neural cell adhesion and also recognise glycolipids with a sulphonylglucuronic acid residue. The saccharide from these glycolipids influences neural cell adhesion
|
|---|