Galactose-Deficient IgA1 as a Candidate Urinary Polypeptide Marker of IgA Nephropathy?

Figure 3

HAA-lectin western blotting confirmed increased urinary excretion of Gd-IgA1 in IgAN patients. Urine samples were normalized to urinary creatinine concentration. IgA western blotting under reducing and nonreducing conditions using urine samples from four patients with IgAN (lanes 1 to 4), two patients with lupus nephritis (lanes 5 and 6), and two healthy controls (lanes 7 and 8). Depending on the severity of proteinuria, varying amounts of IgA were excreted in urine. Notably, all four patients with IgAN, but none of the disease and healthy controls, had polymeric IgA in the urine samples. HAA-lectin western blotting under reducing conditions indicated that all patients with IgAN had urinary HAA-reactive IgA regardless of the amounts of urinary IgA (lane 1: IgAN with severe proteinuria (), lanes 2 and 3: IgAN with moderate proteinuria (), lane 4: IgAN with mild proteinuria (), lanes 5 and 6: lupus nephritis (), and lanes 7 and 8: healthy controls).