biostudies-literatureUnknown11(11)Fukao YIn patients with IgA nephropathy (IgAN), circulatory IgA1 and IgA1 in the mesangial deposits contain galactose-deficient IgA1 (Gd-IgA1). Some of the Gd-IgA1 from the glomerular deposits is excreted in the urine and thus urinary Gd-IgA1 may represent a disease-specific marker. We recruited 338 Japanese biopsy-proven IgAN patients and 120 patients with other renal diseases (disease controls). Urine samples collected at the time of renal biopsy were used to measure Gd-IgA1 levels using a specific monoclonal antibody (KM55 mAb). Urinary Gd-IgA1 levels were significantly higher in patients with IgAN than in disease controls. Moreover, urinary Gd-IgA1 was significantly correlated with the severity of the histopathological parameters in IgAN patients. Next, we validated the use of urinary Gd-IgA1Journal of clinical medicine3173https://www.ebi.ac.uk/biostudies/studies/S-EPMC9181435biostudies-literatureGalactose-Deficient IgA1 as a Candidate Urinary Marker of IgA Nephropathy.PMC9181435Jeong KHLee MLee SHKato RKano TFukao YSuzuki HKim JSNihei YMakita YChang JMSuzuki YNakayama MfalseGalactose-Deficient IgA1 as a Candidate Urinary Marker of IgA Nephropathy.In patients with IgA nephropathy (IgAN), circulatory IgA1 and IgA1 in the mesangial deposits contain galactose-deficient IgA1 (Gd-IgA1). Some of the Gd-IgA1 from the glomerular deposits is excreted in the urine and thus urinary Gd-IgA1 may represent a disease-specific marker. We recruited 338 Japanese biopsy-proven IgAN patients and 120 patients with other renal diseases (disease controls). Urine samples collected at the time of renal biopsy were used to measure Gd-IgA1 levels using a specific monoclonal antibody (KM55 mAb). Urinary Gd-IgA1 levels were significantly higher in patients with IgAN than in disease controls. Moreover, urinary Gd-IgA1 was significantly correlated with the severity of the histopathological parameters in IgAN patients. Next, we validated the use of urinary Gd-IgA12022-01-01T00:00:00Z2022 Jun2025-05-29T21:21:20.89Z2025-02-19T03:51:57.267ZS-EPMC91814353568355710.3390/jcm11113173