Up-regulation of IL-10R1 expression is required to render human neutrophils fully responsive to IL-10.
We have recently shown that IL-10 fails to trigger Stat3 and Stat1 tyrosine phosphorylation in freshly isolated human neutrophils. In this study, we report that IL-10 can nonetheless induce Stat3 tyrosine phosphorylation and the binding of Stat1 and Stat3 to the IFN-gamma response region or the high-affinity synthetic derivative of the c-sis-inducible element in neutrophils that have been cultured for at least 3 h with LPS. Similarly, the ability of IL-10 to up-regulate suppressor of cytokine signaling (SOCS)-3 mRNA was dramatically enhanced in cultured neutrophils and, as a result, translated into the SOCS-3 protein. Since neutrophils' acquisition of responsiveness to IL-10 required de novo protein synthesis, we assessed whether expression of IL-10R1 or IL-10R2 was modulated in cultured neutrophils. We detected constitutive IL-10R1 mRNA and protein expression in circulating neutrophils, at levels which were much lower than those observed in autologous monocytes or lymphocytes. In contrast, IL-10R2 expression was comparable in both cell types. However, IL-10R1 (but not IL-10R2) mRNA and protein expression was substantially increased in neutrophils stimulated by LPS. The ability of IL-10 to activate Stat3 tyrosine phosphorylation and SOCS-3 synthesis and to regulate IL-1 receptor antagonist and macrophage-inflammatory protein 1beta release in LPS-treated neutrophils correlated with this increased IL-10R1 expression, and was abolished by neutralizing anti-IL-10R1 and anti-IL-10R2 Abs. Our results demonstrate that the capacity of neutrophils to respond to IL-10, as assessed by Stat3 tyrosine phosphorylation, SOCS-3 expression, and modulation of cytokine production, is very dependent on the level of expression of IL-10R1.
Crepaldi
L
L
Department of Pathology, General Pathology Unit, University of Verona, Verona, Italy.
Gasperini
S
S
Lapinet
J A
JA
Calzetti
F
F
Pinardi
C
C
Liu
Y
Y
Zurawski
S
S
de Waal Malefyt
R
R
Moore
K W
KW
Cassatella
M A
MA
D002469:Cell Separation; D002478:Cells, Cultured; D016207:Cytokines / Q000378:metabolism; D004268:DNA-Binding Proteins / Q000378:metabolism; D006801:Humans; D007106:Immune Sera / Q000494:pharmacology; D016753:Interleukin-10 / Q000378:metabolism* / Q000494:pharmacology / Q000502:physiology; D008070:Lipopolysaccharides / Q000494:pharmacology; D009504:Neutrophils / Q000276:immunology* / Q000378:metabolism*; D010766:Phosphorylation; D011485:Protein Binding / Q000276:immunology; D014176:Protein Biosynthesis; D011506:Proteins / Q000235:genetics / Q000502:physiology; D012333:RNA, Messenger / Q000096:biosynthesis; D018123:Receptors, Interleukin / Q000037:antagonists & inhibitors / Q000096:biosynthesis* / Q000235:genetics / Q000276:immunology; D053701:Receptors, Interleukin-10; D012097:Repressor Proteins; D050796:STAT3 Transcription Factor; D015398:Signal Transduction / Q000235:genetics / Q000276:immunology; D000071223:Suppressor of Cytokine Signaling 3 Protein; D050826:Suppressor of Cytokine Signaling Proteins; D015534:Trans-Activators / Q000378:metabolism; D014157:Transcription Factors; D014443:Tyrosine / Q000378:metabolism; D015854:Up-Regulation / Q000276:immunology*
D016207:Cytokines; D004268:DNA-Binding Proteins; D007106:Immune Sera; D008070:Lipopolysaccharides; D011506:Proteins; D012333:RNA, Messenger; D018123:Receptors, Interleukin; D053701:Receptors, Interleukin-10; D012097:Repressor Proteins; C106644:SOCS3 protein, human; D050796:STAT3 Transcription Factor; C494086:STAT3 protein, human; D000071223:Suppressor of Cytokine Signaling 3 Protein; D050826:Suppressor of Cytokine Signaling Proteins; D015534:Trans-Activators; D014157:Transcription Factors; D016753:Interleukin-10; D014443:Tyrosine