Fc alpha R expression on polymorphonuclear leukocyte and superoxide generation in IgA nephropathy.
Superoxide (O2-) production and Fc alpha R antigen expression of circulating polymorphonuclear leukocytes (PMNL) isolated from patients with IgA nephropathy (IgAN) and non-IgA mesangial proliferative glomerulonephritis (PGN) and healthy volunteers were investigated to establish their biological importance in the immunopathogenesis of mesangial proliferative glomerulonephritis. PMNL from both patient groups showed increased O2- production when stimulated with N-formyl methionyl leucyl phenylalanine (FMLP) and phorbol myristate acetate (PMA). The increased O2- generation demonstrated a positive correlation with the degree of proteinuria. Aggregated IgA caused enhanced O2- production only in patients with IgAN who also showed a significant correlation with proteinuria. Increased expression of Fc alpha R on circulating PMNL was observed in IgAN patients as determined by flow cytometric analysis. The amount of Fc alpha R on PMNL was positively correlated with O2- generation triggered with IgA aggregates. These results suggest that: 1. Circulating PMNL may potentially be participating in the pathogenesis of glomerular injury in mesangial proliferative glomerulonephritis, and 2. IgA aggregates/immune complexes may contribute to the immunopathogenesis of IgAN through augmenting the Fc alpha receptor-mediated generation of superoxide anion.
Kashem
A
A
Department of Internal Medicine, Tokai University, Kanagawa, Japan.
Endoh
M
M
Nomoto
Y
Y
Sakai
H
H
Nakazawa
H
H
D000328:Adult; D000911:Antibodies, Monoclonal; D015703:Antigens, CD; D005260:Female; D005434:Flow Cytometry; D005921:Glomerulonephritis / Q000378:metabolism; D005922:Glomerulonephritis, IGA / Q000378:metabolism* / Q000473:pathology; D006801:Humans; D007070:Immunoglobulin A / Q000378:metabolism; D008297:Male; D009240:N-Formylmethionine Leucyl-Phenylalanine / Q000494:pharmacology; D009504:Neutrophils / Q000378:metabolism* / Q000473:pathology; D011961:Receptors, Fc / Q000378:metabolism*; D017452:Receptors, IgG / Q000378:metabolism; D013481:Superoxides / Q000378:metabolism*; D013755:Tetradecanoylphorbol Acetate / Q000494:pharmacology
D000911:Antibodies, Monoclonal; D015703:Antigens, CD; C036832:Fc(alpha) receptor; D007070:Immunoglobulin A; D011961:Receptors, Fc; D017452:Receptors, IgG; D013481:Superoxides; D009240:N-Formylmethionine Leucyl-Phenylalanine; D013755:Tetradecanoylphorbol Acetate