Related Experiment Videos
Production of interleukin 1 in glomerular cell cultures from patients with rapidly progressive crescentic
K Matsumoto1, J Dowling, R C Atkins
1Department of Nephrology, Prince Henry's Hospital, Melbourne, Australia.
Abstract:
Interleukin 1 (IL-1) activity was measured in glomerular culture supernatants from 3 patients with rapidly progressive crescentic glomerulonephritis (RPGN). Macrophages were present in both capillary tufts and cellular crescents as identified by OKM1-positive cells on immunoperoxidase labelling. Glomeruli from 4 rejecting renal cadaver allografts were used as a disease control, in addition to glomeruli from a normal kidney. IL-1 activity as measured by the thymocyte proliferation assay was greater in the supernatants from cultured glomerular outgrowths of patients with crescentic GN than in those from rejected renal allografts and glomeruli isolated from the normal tissue. IL-1 production from cultured glomerular cells from patients with RPGN was detectable in the serum-free conditioned media harvested after 3 days of culture and increased in a stepwise fashion over 28 days of culture. The prominent feature of the glomerular outgrowth of the glomeruli in the RPGN patients was the presence of large numbers of macrophages, which were not present in cultured control glomeruli. These findings indicate that the immunoregulatory aberration in patients with RPGN may in part be due to IL-1 production by activated macrophages.
Insights
Rapidly progressive glomerulonephritis (RPGN) involves increased interleukin-1 (IL-1) production by macrophages within the glomeruli. This suggests IL-1 plays a key role in the immune dysregulation seen in RPGN patients.
Area of Science:
- Nephrology
- Immunology
- Cell Biology
Background:
- Rapidly progressive crescentic glomerulonephritis (RPGN) is a severe kidney disease characterized by rapid loss of kidney function.
- The role of specific cytokines, such as interleukin-1 (IL-1), in the pathogenesis of RPGN is not fully understood.
Observation:
- Macrophages, identified by OKM1-positive cells, were abundant in glomeruli from RPGN patients, both in capillary tufts and cellular crescents.
- Glomeruli from normal kidneys and rejected renal allografts served as controls.
- Cultured glomerular outgrowths from RPGN patients exhibited significantly higher IL-1 activity compared to controls.
Findings:
- Interleukin-1 (IL-1) activity was markedly elevated in supernatants from cultured glomeruli of RPGN patients.
- IL-1 production by cultured glomerular cells from RPGN patients was detectable within 3 days and increased over 28 days.
- Activated macrophages were a prominent feature in RPGN glomeruli outgrowths, correlating with increased IL-1 levels.
Implications:
- These findings suggest that activated macrophages in the glomeruli are a significant source of IL-1 in RPGN.
- IL-1 production by these macrophages may contribute to the immunoregulatory abnormalities observed in rapidly progressive glomerulonephritis.
- Targeting macrophage-derived IL-1 could represent a potential therapeutic strategy for RPGN.