Regulation of macrophage functions by cytokine and 1,25-dihydroxyvtamin D_3 on glomerulonephritis

点击翻译按钮获取中文摘要

One representative of a number of severe lesions that occur outside the glomerular capillaries and involve podocytes is crescentic glomerulonephritis. The question of whether the crescent-forming cells are derived from glomerular epithelial cells or monocytes/macrophages is highly controversial and has not yet been clarified. To investigate pathophysiology of podocyte in crescentic glomerulonephritis, we attempted to establish methods for culturing cells confirmed to be derived from podocytes, focusing particularly on the relationship between podocytes and macrophages.Non-adherent cells of unknown origin that grew from normal rat isolated glomerular cultures increased in number, reaching a total of 3.5 x 10^5/ml on day 11. They showed several characteristics of macrophages, the expression of specific antigens and enzyme, morphology, and production of H_2O_2. They expressed FxlA,but lacked the expressions of Thy1.1 or factor VIII.A morphological kinetic study on day 3-11 of culture show … More ed that the cells with foot processes on the glomerular basement membrane (GBM) changed into macrophagic cells (MC) and migrated from the glomeruli. Immunofluorescence double staining indicated that the cells migrated from glomerular surface on day 8 were both anti-podocalyxin and ED-1 positive. Furthermore, immunoelectron microscopy revealed that the ED-1 positive cells were located on GBM.Pretreatment with an anti-macrophages and -Thy1.1 antibodies both with complement did not reduce the number of MC,while pretreatment with puromycin aminonucleoside predominantly reduced the number of MC.Predominant decrease in the number of glomerular macrophage by gamma-irradiation did not result in the reduction in the number of MC.MC derived from glomerular cultures of bone marrow chimeric rats expressed the Ia antigen originated from recipient, indicating that MC is not derived from bone marrow cells. Macrophage colony-stimulating factor accelerated the speed of the change into MC and granulocyte-macrophage colony-stimulating factor dramatically enhanced its degree with increase of cell number on day 8.We concluded that podocytes change into MC in normal rat glomerular culture and the change is enhanced by CSFs. The results provide a completely new insight into the origin of crescent forming cells. Less