Immunoglobulin A1 protease: a new therapeutic candidate for immunoglobulin A nephropathy.

Immunoglobulin A nephropathy (IgAN), characterized by predominant or exclusive deposition of IgA1 in glomerular mesangium, is the most common primary glomerulonephritis worldwide. At present, the treatment is always limited due to the incomplete understanding of the pathogenesis of IgAN. Mesangial deposited IgA1 is the common final pathway leading to glomerulonephritis and renal injury. IgA1 protease, a proteolytic enzyme with strict substrate specificity for human IgA1, may be an effective therapeutic candidate for IgAN by removing the mesangial deposited IgA1.