Cytokine- and LPS-induced synthesis of interleukin-8 from human mesangial cells.
The cytokine neutrophil-activating peptide-1/interleukin-8 (NAP/IL-8) activates neutrophils (PMN) and elicits selective diapedesis of PMN into the extracellular space. The glomerular mesangial cell (MC) is a specialized pericyte that controls glomerular filtration and synthesizes and responds to a variety of cytokines. Because of its location within the glomerulus, the MC is in a pivotal position to orchestrate events underlying immune injury. Since immune-injured glomeruli have been shown to produce NAP/IL-8 activity in vitro, we assessed whether lipopolysaccharide (LPS)- or cytokine-activated MC might be a source of this activity. Pure human MC, devoid of monocyte/macrophage and fibroblast contamination, were grown by explant from collagenase-treated glomeruli. Human recombinant interleukin-1 alpha (IL-1 alpha, 20 ng/ml), IL-1 beta (50 ng/ml), tumor necrosis factor alpha (TNF, 100 ng/ml) and lipopolysaccharide (LPS, 10 micrograms/ml) stimulated release of a neutrophil chemotactic factor from cultured MC. Both concentrated (fivefold) and unconcentrated MC supernatants stimulated directed neutrophil migration under agarose at a level similar to that of the bacterial chemotactic factor, FMLP. In contrast, unstimulated MC-conditioned media and IL-1 alpha, IL-1 beta. TNF and LPS in medium alone did not directly induce PMN migration. Molecular sizing studies using sequential membrane ultrafiltration identified significant TNF-stimulated, MC-derived chemotactic activity in the 3000 to 10000 kD fraction. An anti-NAP/IL-8 monoclonal antibody, 46E5, significantly inhibited PMN chemotaxis stimulated by TNF-stimulated, MC-conditioned media in a dose-dependent manner.(ABSTRACT TRUNCATED AT 250 WORDS)
Kusner
D J
DJ
Department of Medicine, School of Medicine, Case Western Reserve University, Cleveland, Ohio.
Luebbers
E L
EL
Nowinski
R J
RJ
Konieczkowski
M
M
King
C H
CH
Sedor
J R
JR
D002478:Cells, Cultured; D005591:Chemical Fractionation; D016207:Cytokines / Q000494:pharmacology*; D004305:Dose-Response Relationship, Drug; D005920:Glomerular Mesangium / Q000166:cytology / Q000378:metabolism*; D006801:Humans; D016209:Interleukin-8 / Q000096:biosynthesis* / Q000235:genetics; D007700:Kinetics; D008070:Lipopolysaccharides / Q000494:pharmacology*; D009693:Nucleic Acid Hybridization; D012333:RNA, Messenger / Q000235:genetics / Q000378:metabolism; D014158:Transcription, Genetic; D014409:Tumor Necrosis Factor-alpha / Q000494:pharmacology
D016207:Cytokines; D016209:Interleukin-8; D008070:Lipopolysaccharides; D012333:RNA, Messenger; D014409:Tumor Necrosis Factor-alpha