Proliferative activity of intrinsic cell populations in the normal human kidney

The proliferative activity of various normal human renal cell populations is unknown. Recently, antibodies to cell proliferation-associated nuclear proteins, such as proliferating cell nuclear antigen (PCNA) and KI-67, which are applicable to archival paraffin sections, became available. With antibodies to PCNA and Ki-67 after microwave pretreatment of the paraffin sections, the proliferation indexes (ratio of positive nuclei with PCNA and Ki-67 antibodies/all nuclei counted x 100, i.e. percentage of positive cells) of 12 different intrinsic renal cell populations in 20 normal human kidneys have been determined. The following proliferation indexes (percentages of positive cells) were found with the PCNA and the Ki-67 antibodies, respectively: proximal tubular epithelium, 0.22, 0.24; thin limb of Henle, 0.29, 0.30; thick ascending limb of Henle, 0.32, 0.29; distal tubular epithelium (distal convoluted tubules and cortical collecting ducts, 0.33, 0.44; medullary collecting ducts, 0.32, 0.3; glomerular mesangial cells, 0.07, 0.12; glomerular visceral epithelial cells, 0.04, 0.08; glomerular parietal epithelial cells, 0.07, 0.1; glomerular capillary endothelium, 0.42, 0.47; peritubular capillary endothelial cells, 0.38, 0.43; endothelium of large intrarenal vessels (arteries and veins), 0.09, 0.12. Thus, normally capillary endothelium (glomerular and peritubular) appears to have the highest proliferation index in the human kidney by these techniques. These results indicate major variation in the proliferative activity of normal human renal cell populations, along with a significant correlation between PCNA and Ki-67 staining. Furthermore, this study provides normal values for the proliferative activity of different human renal cell populations.(ABSTRACT TRUNCATED AT 250 WORDS)