Incompleteness of O-glycans at the Hinge Region of IgA1 and IgA Nephropathy
IgA nephropathy (IgAN) was first reported as a disease by Berger. The definite diagnosis of IgAN can be made by detection of deposited IgA in the glomerular mesangial region by renal biopsy. IgAN was well known as one of the most common primary glomerulonephritis forms in the world. The frequency of IgAN in renal diseases is considered to be 20–30% in Asia and Europe. Among IgAN patients, about 40% of the patients in Japan develop renal failure within 20 years. The patient is often left without treatment because the symptoms were usually slight (protein urea and episodes of hematuria). Glomerular deposited IgA was dominantly the IgA1 subclass. The disease was thought to occur due to the deposition of an immune complex. Participation of many antigens, such as a food antigen, virus and bacteria, were reported as candidates. In addition, the implication of an abnormality in the molecular structure, especially a hinge mucin-type sugar chain, of IgA1 was reported mainly based on our research results in this article (Fig. 1).
KeywordsHinge Region Nephrol Dial Transplant IgAN Patient IgA1 Subclass IgA1 Molecule
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