The distribution of epithelial membrane antigen in the kidney and its tumours.

The distribution of epithelial membrane antigen (EMA) in the kidney and its tumours has been studied using a polyclonal anti-EMA antiserum and the immunoperoxidase-antiperoxidase technique (PAP). Twelve fetal and 10 adult kidneys examined showed EMA to be confined to the distal tubular or collecting duct epithelium or their embryological precursors. The examination of 55 primary renal tumours showed EMA to be present on the epithelial tumours, on tubular epithelium in nephroblastoma, but not on mesenchymal tumour cells nor on undifferentiated areas of nephroblastoma.