In situ demonstration of renal tubular regeneration using the monoclonal antibody Ki67

The murine monoclonal antibody Ki67 recognizes a nuclear antigen present in all phases of the cell cycle except Go and can be used with a simple indirect immunohistochemical technique to demonstrate cell proliferation in tissue sections. This antibody was applied to 37 unselected renal biopsies showing a wide variety of histological appearances. Ki67-positive nuclei were seen most frequently in tubular epithelium in acute tubulo-interstitial pathology, particularly in renal allograft rejection. Tubular epithelial staining ranged from 0 to 10% of cells. In chronic nephropathies few tubular cells were stained. Staining was seen in glomerular crescents, but was rare in glomerular tufts except those that showed mesangial proliferation where occasional cells stained. This study demonstrates that information regarding cellular proliferation in renal biopsies can be easily obtained using Ki67 immunostaining. This is likely to be a useful investigative tool and may provide clinically useful information.