lewis-x-antigen and Glomerulonephritis--IGA

Endocapillary proliferation (EP) is a common pathological finding in proliferative glomerulonephritis (GN). Its appearance indicates the presence of active lesions of GN. In this study, we reinvestigated the pathological features of EP.. Cell markers that included CD15, CD68, CD45RO, CD31 and alpha-smooth muscle actin (alpha-SMA) were used to identify the intraglomerular cells in renal biopsy tissues collected from patients with post-streptococcal acute GN (PSAGN), methicillin-resistant Staphylococcus aureus-associated GN (MRSAGN) with or without EP, membranoproliferative GN (MPGN) with or without EP, Henoch-Schönlein nephritis, immunoglobulin A nephropathy, membranous nephropathy and minimal change nephrotic syndrome. Proliferating cells and apoptotic cells were investigated simultaneously.. The glomerular infiltrating polymorphonuclear leukocytes, macrophages, T cells, mesangial cells and endothelial cells were enumerated. In PSAGN, the glomerulus was enlarged and all cell types were greatly increased. In MRSAGN EP, the glomerulus was slightly enlarged with abundant infiltrating leukocytes and monocyte/macrophages and had moderate mesangial cell proliferation with negligible endothelial cell proliferation. In MPGN, the glomerulus markedly enlarged with multiple monocyte/macrophages and remarkable mesangial proliferation. The mesangial cells in EP glomeruli were highly activated as evidenced by alpha-SMA expression, particularly in PSAGN.. This is the first report to use monoclonal antibodies specific for cell markers to quantitatively analyze and compare the proliferating cell types in EP glomeruli in different forms of GN. The results suggest that identification of the presence of polymorphonuclear leukocytes in the capillary lumen might help in differentiating between glomerular global and segmental EP.

Topics: Actins; Antibodies, Monoclonal; Antigens, CD; Antigens, Differentiation, Myelomonocytic; Apoptosis; Biomarkers; Capillaries; Cell Proliferation; Female; Fucosyltransferases; Glomerulonephritis; Glomerulonephritis, IGA; Glomerulonephritis, Membranoproliferative; Humans; IgA Vasculitis; Immunohistochemistry; Kidney Glomerulus; Leukocyte Common Antigens; Lewis X Antigen; Male; Nephrosis, Lipoid; Platelet Endothelial Cell Adhesion Molecule-1

Clinical manifestation of IgA nephropathy (IgAN) strikingly occurs after respiratory tract infections. An intestinal inflammation has also been described. We hypothesized that the intestinal inflammation should manifest itself as an increase in inflammatory cells and mucosal cyclooxygenase 2 (COX-2) expression.. By using immunohistochemistry, we determined the phenotype and quantity of inflammatory cells in duodenal biopsy specimens from 17 IgAN patients. Control material comprised 18 patients undergoing gastroscopy because of dyspepsia.. All the biopsy specimens disclosed normal villous architecture. In IgAN, CD3(+) cells and COX-2-positive cells were significantly increased and J chain-producing plasma cells were significantly decreased. CD3(+) cells coexpressed COX-2 protein and COX-2-positive cells also expressed CD45RO antigen. The number of lymphocytes correlated significantly with serum IgA and COX-2-expression with serum IgA and the degree of hematuria. COX-2-positive subepithelial fibroblasts were a conspicuous finding in IgAN. In CD68(+) and CD15(+) cells, a significant increase was seen. Many of these cells also expressed COX-2 protein. CD15(+) positivity correlated significantly with proteinuria in IgAN.. Our results indicate that small bowel inflammation in IgAN shows itself as an increased number of mucosal inflammatory cells. However, polymeric IgA production is significantly decreased. An increased mucosal COX-2 expression suggests activation of the inflammatory cells and the degree of inflammation significantly correlates with serum IgA and the amount of proteinuria and hematuria. Subepithelial fibroblasts seem also to be involved in the inflammatory reaction.

Topics: Adult; Cyclooxygenase 2; Duodenum; Female; Glomerulonephritis, IGA; Humans; Immunoglobulin A; Immunohistochemistry; Leukocyte Common Antigens; Lewis X Antigen; Male; Membrane Proteins; Middle Aged; Prostaglandin-Endoperoxide Synthases

An important aspect in glomerular nephritic processes is the enhanced influx of leukocytes into the glomerulus.. To investigate the mechanisms of intraglomerular leukocyte infiltration in IgA nephropathy (IgA-N) and membranoproliferative glomerulonephritis type I (MPGN-I), we immunohistochemically examined the intraglomerular expression of leukocyte function-associated antigen-1 (LFA-1, CD11a/CD18), macrophage-1 (Mac-1, CD11b/CD18) and intercellular adhesion molecule-1 (ICAM-1, CD54) together with glomerular deposition of C3c and fibrinogen.. In IgA-N (n=42), LFA-1+ cells were distributed mainly in glomeruli with intense expression of ICAM-1, and there was a positive correlation (P<0.001) between the number of LFA-1+ cells and the degree of ICAM-1 expression. Mac-1+ cells had no correlation with glomerular C3c deposition, but had a significant correlation with fibrinogen deposition (P<0.05). The number of LFA-1+ cells was significantly greater than of Mac-1+ cells (P<0.05). The number of LFA-1+ cells was strongly correlated with that of CD68+ cells (P<0.00001). In MPGN-I (n= 43), on the contrary, Mac-1+ cells correlated only with C3c deposition (P<0.001), and they were observed mainly in peripheral loops of glomerular capillaries where C3c was deposited with a similar distribution. However, there was no relationship between LFA-1+ cells and ICAM-1 expression. The number of Mac-1+ cells was greater than that of LFA-1+ cells (P<0.0001), and most Mac-1+ cells were identical to CD15+ cells.. These results indicate the possibility that different mechanisms may cause glomerular leukocyte infiltration in various forms of human glomerulonephritis. The LFA-1/ICAM-1 pathway may play an important role in glomerular leukocyte infiltration in IgA-N, while the Mac-1/complement pathway may be important in MPGN-I. The former may promote mainly the infiltration of CD68+ cells, and the latter may promote that of CD15+ cells. In addition, Mac-1+ cells may act as fibrinogen and complement receptors in IgA-N and MPGN-I, respectively.

Topics: Antigens, CD; Antigens, Differentiation, Myelomonocytic; Complement C3c; Fibrinogen; Glomerulonephritis, IGA; Glomerulonephritis, Membranoproliferative; Humans; Immunoenzyme Techniques; Intercellular Adhesion Molecule-1; Leukocytes; Lewis X Antigen; Lymphocyte Function-Associated Antigen-1; Macrophage-1 Antigen