Glomerular expression of interleukin-1 receptor antagonist and interleukin-1 beta genes in antibody-mediated glomerulonephritis.
Interleukin-1 (IL-1) is a powerful proinflammatory cytokine whose function is modulated by a natural IL-1 receptor antagonist (IL-1ra). There are few data about kinetics of in vivo synthesis of IL-1ra at tissue level, except in response to bacterial endotoxin. The purpose of this study was to examine the kinetics of local expression of IL-1ra gene in relation to IL-1 beta gene in a model of anti-glomerular basement membrane antibody-mediated glomerulonephritis. Rats were killed in groups of 5 or 6 at 0, 4, 6, 24, 48, and 96 hours after induction of glomerulonephritis. Messenger RNA for IL-1ra and IL-1 beta was undetectable by Northern blot in normal glomeruli but increased markedly 4 to 6 hours after induction of nephritis. The increase in IL-1ra mRNA was more sustained than that of IL-1 beta mRNA. In situ hybridization showed that IL-1 beta mRNA increased diffusely within glomeruli, while IL-1ra mRNA was expressed more discretely. Expression of these mRNA in noninflamed tissues, spleens and lungs, was different, particularly increase in IL-1ra mRNA was more substantial than that of IL-1 beta. These observations suggest that differential expression of IL-1ra and IL-1 beta might focus inflammation in glomeruli while protecting more distant sites. They also raise the possibility of reducing glomerular injury by therapeutic measures that upregulate glomerular synthesis of IL-1ra while reducing that of IL-1 beta.
Tam
F W
FW
Department of Medicine, Royal Postgraduate Medical School, Hammersmith Hospital, London, United Kingdom.
Smith
J
J
Cashman
S J
SJ
Wang
Y
Y
Thompson
E M
EM
Rees
A J
AJ
D000818:Animals; D001483:Base Sequence; D015152:Blotting, Northern; D004195:Disease Models, Animal; D005786:Gene Expression Regulation; D005921:Glomerulonephritis / Q000235:genetics / Q000378:metabolism* / Q000473:pathology; D017403:In Situ Hybridization; D053590:Interleukin 1 Receptor Antagonist Protein; D007375:Interleukin-1 / Q000235:genetics / Q000378:metabolism*; D007678:Kidney Glomerulus / Q000378:metabolism*; D008168:Lung / Q000378:metabolism; D008297:Male; D008969:Molecular Sequence Data; D012333:RNA, Messenger / Q000378:metabolism; D051381:Rats; D017207:Rats, Sprague-Dawley; D017472:Receptors, Interleukin-1 / Q000037:antagonists & inhibitors*; D012795:Sialoglycoproteins / Q000235:genetics / Q000378:metabolism*; D013154:Spleen / Q000378:metabolism; D013997:Time Factors
D053590:Interleukin 1 Receptor Antagonist Protein; D007375:Interleukin-1; D012333:RNA, Messenger; D017472:Receptors, Interleukin-1; D012795:Sialoglycoproteins