CMA1 and IgA glomerulonephritis: While these data are completely in line with significant renal infiltration by chymase-positive MCs, such as observed in rejected kidneys [45], IgA nephropathy [60,61], diabetic [58,62] and hypertensive nephropathy [63], as well as in autosomal polycystic kidney disease [64], they may simply reflect the relative amount of ACE and chymase in tissues, without being functionally relevant.