Nuclear autoantigen CENP-B transactivation of the epidermal growth factor receptor via chemokine receptor 3 in vascular smooth muscle cells.
OBJECTIVE
We have previously found that the CENP-B nuclear autoantigen, which is specifically targeted by autoantibodies in the limited cutaneous form of systemic sclerosis, behaved as a potent migratory factor for human pulmonary artery smooth muscle cells (PASMCs). Other recent studies have shown that several disease-associated autoantigens induced cell migration by interacting with various chemokine receptors. Prompted by this hypothesis, we undertook this study to determine whether CENP-B interacts with chemokine receptors on the surface of human PASMCs, to explore the relevant signaling pathways, and to characterize the effects of anti-CENP-B binding on SMC stimulation.


METHODS
To demonstrate the expression of specific chemokine receptors by human PASMCs at both the messenger RNA and protein levels, reverse transcription-polymerase chain reaction, immunoblotting, and flow cytometry analyses were performed. Desensitization studies and specific inhibitors were used to further identify the CENP-B target on the surface of human PASMCs.


RESULTS
Our data strongly suggested that CENP-B used chemokine receptor 3 (CCR3) to mediate human PASMCs signaling. Moreover, several lines of evidence indicated that CENP-B binding subsequently stimulated the cross-talk between CCR3 and epidermal growth factor receptor (EGFR) via a matrix metalloprotease-dependent mechanism that involved the processing of heparin-binding EGF-like growth factor. Transactivation of the EGFR through CCR3 was found to be a critical pathway that elicits MAP kinase activation and secretion of cytokines such as interleukin-8. Finally, anti-CENP-B autoantibodies were found to abolish this signaling pathway, thus preventing CENP-B from transactivating EGFR and exerting its cytokine-like activities toward vascular smooth muscle cells.


CONCLUSIONS
The identification of CENP-B as a CCR3 ligand opens up new perspectives for the study of the pathogenic role of anti-CENP-B autoantibodies.
Robitaille
Geneviève
G
Notre-Dame Hospital, Centre Hospitalier de l'Université de Montréal, and Université de Montréal, Montréal, Québec, Canada.
Christin
Marie-Soleil
MS
Clément
Isabelle
I
Senécal
Jean-Luc
JL
Raymond
Yves
Y
D001323:Autoantibodies / Q000494:pharmacology; D002478:Cells, Cultured; D051936:Centromere Protein B / Q000235:genetics* / Q000378:metabolism*; D066246:ErbB Receptors / Q000378:metabolism*; D006801:Humans; D016209:Interleukin-8 / Q000378:metabolism; D020929:Mitogen-Activated Protein Kinase Kinases / Q000378:metabolism; D009131:Muscle, Smooth, Vascular / Q000166:cytology / Q000187:drug effects / Q000378:metabolism*; D011651:Pulmonary Artery / Q000166:cytology; D012333:RNA, Messenger / Q000378:metabolism; D020239:Receptor Cross-Talk / Q000502:physiology; D054397:Receptors, CCR3 / Q000378:metabolism*; D012595:Scleroderma, Systemic / Q000378:metabolism; D015398:Signal Transduction / Q000502:physiology; D015533:Transcriptional Activation / Q000502:physiology*
D001323:Autoantibodies; C515350:CCR3 protein, human; C497926:CENPB protein, human; D051936:Centromere Protein B; D016209:Interleukin-8; D012333:RNA, Messenger; D054397:Receptors, CCR3; D066246:ErbB Receptors; D020929:Mitogen-Activated Protein Kinase Kinases