期刊名称：Journal of Clinical Biochemistry and Nutrition
印刷版ISSN：0912-0009
电子版ISSN：1880-5086
出版年度：2000
卷号：28
期号：2
页码：81-89
DOI：10.3164/jcbn.28.81
出版社：The Society for Free Radical Research Japan
摘要：N -Glycan structures of Type I cryoglobulin in 3 different samples are reported in detail. The three sample cryoglobulins were purified from sera of monoclonal immunoglobulin G (IgG) 1-κ type cryoglobulinemia: two of them from patients with multiple myeloma (cases 1 and 2) and one from a patient with Sjögren's syndrome (case 3). Asparagine-linked glycan portions of these cryoglobulins were released by digestion with glycoamidase A (from sweet almond), and the reducing ends of the N -glycans were reductively aminated with 2-aminopyridine. The derivatized N -glycans were separated and structurally identified by a multi-dimensional mapping technique on high performance liquid chromatography (HPLC) columns. The HPLC profiles of N -glycans from these patients were compared with that profile from healthy persons. The N -glycan molecules from the 3 different IgG proteins revealed individually abnormal profiles. A glycoform containing 2 galactose residues predominated in case 1. In contrast, no galactose was found in the predominant glycoforms in cases 2 and 3. Moreover, an unusually high content of bisecting N -acetylglucosamine characterized one of the predominant glycoforms in case 2. In spite of these striking N -glycan abnormalities, no clear mechanism that could cause cryoglobulinemia was found.
