Detection of nuclear factor-kappaB in IgA nephropathy using Southwestern histochemistry.
BACKGROUND
The transcription factor nuclear factor-kappaB (NF-kappaB) is involved in inflammatory and immune responses through induction of various cytokines and growth factors. The aim of this study is to examine the correlation between NF-kappaB expression and severity of tissue injury in immunoglobulin A (IgA) nephropathy and the mechanism of such correlation.


METHODS
The study included 43 renal tissue samples from 28 patients, including 28 samples of IgA nephropathy, 5 samples of non-IgA mesangial proliferative glomerulonephritis (non-IgA nephropathy), and 10 samples with nonproliferative glomerulonephritis (membranous nephropathy [MN] n = 5; minimal change nephrotic syndrome [MCNS]; n = 5). Tissue sections were examined by Southwestern histochemistry and immunohistochemistry for monocyte chemoattractant protein-1 (MCP-1), granulocyte-macrophage colony-stimulating factor (GM-CSF), and intercellular cell adhesion molecule-1 (ICAM-1), which are regulated by NF-kappaB. Normal portions of surgically resected kidney with adenocarcinoma served as controls.


RESULTS
In normal kidney, MCNS, and MN sections, NF-kappaB expression was detected in a few mesangial cells and tubular epithelial cells. In IgA nephropathy and non-IgA nephropathy samples, NF-kappaB was expressed in mesangial, glomerular endothelial and epithelial cells, tubular epithelial cells, and infiltrating cells. Expression in both glomeruli and interstitium correlated with progression of tissue injury. In IgA nephropathy samples, MCP-1 and GM-CSF expression was increased in both glomeruli and interstitium and correlated with progression of tissue injury. Glomerular ICAM-1 expression was weaker in severe lesions, whereas interstitial expression correlated with progression of tissue injury.


CONCLUSIONS
Our results indicate that NF-kappaB is involved in the progression of tissue injury in IgA nephropathy through the induction of transcriptionally regulated genes.
Ashizawa
Mamiko
M
Second Department of Internal Medicine, Division of Nephrology, Nagasaki University School of Medicine, Nagasaki, Japan.
Miyazaki
Masanobu
M
Abe
Katsushige
K
Furusu
Akira
A
Isomoto
Hajime
H
Harada
Takashi
T
Ozono
Yoshiyuki
Y
Sakai
Hideto
H
Koji
Takehiko
T
Kohno
Shigeru
S
D000230:Adenocarcinoma / Q000378:metabolism / Q000473:pathology; D000328:Adult; D026501:Blotting, Southwestern; D018932:Chemokine CCL2 / Q000032:analysis; D018450:Disease Progression; D042783:Endothelial Cells / Q000378:metabolism / Q000648:ultrastructure; D004847:Epithelial Cells / Q000378:metabolism / Q000648:ultrastructure; D005260:Female; D005786:Gene Expression Regulation; D005922:Glomerulonephritis, IGA / Q000235:genetics / Q000378:metabolism* / Q000473:pathology; D015433:Glomerulonephritis, Membranous / Q000235:genetics / Q000378:metabolism / Q000473:pathology; D016178:Granulocyte-Macrophage Colony-Stimulating Factor / Q000032:analysis; D006801:Humans; D018799:Intercellular Adhesion Molecule-1 / Q000032:analysis; D007668:Kidney / Q000378:metabolism* / Q000473:pathology; D007678:Kidney Glomerulus / Q000378:metabolism / Q000648:ultrastructure; D007680:Kidney Neoplasms / Q000378:metabolism / Q000473:pathology; D007684:Kidney Tubules / Q000378:metabolism / Q000648:ultrastructure; D008297:Male; D008875:Middle Aged; D016328:NF-kappa B / Q000032:analysis*; D009402:Nephrosis, Lipoid / Q000235:genetics / Q000378:metabolism / Q000473:pathology; D016037:Single-Blind Method; D014158:Transcription, Genetic
D018932:Chemokine CCL2; D016328:NF-kappa B; D018799:Intercellular Adhesion Molecule-1; D016178:Granulocyte-Macrophage Colony-Stimulating Factor