The Cytological Localization of Erythropoietin in the Human Kidney Using the Fluorescent Antibody Technique

Abstract
Summary Intense fluorescent staining of cells in the glomerular tuft has been demonstrated in an anemic human kidney following application of an antibody to erythropoietin using the indirect fluorescent antibody technique. The fluorescence was more localized in the cytoplasm of epithelial cells in the periphery of the glomerular tuft. A slight amount of fluorescent staining in the glomeruli was blocked by a highly purified preparation of human urinary erythropoietin. The present studies suggest that the visceral epithelial cell of the glomerular tuft is the most likely source of erythropoietin.