Paper
Document
Download
Flag content
1

Osteopontin Links Myeloid Activation and Disease Progression in Systemic Sclerosis

1
TipTip
Save
Document
Download
Flag content

Abstract

Progressive lung fibrosis is a major cause of mortality in systemic sclerosis (SSc) patients, but the underlying mechanisms remain unclear. We demonstrate that immune complexes (ICs) activate human monocytes to promote lung fibroblast migration partly via osteopontin (OPN) secretion, which is amplified by autocrine monocyte colony stimulating factor (MCSF) and interleukin-6 (IL-6) activity. Bulk and single-cell RNA sequencing demonstrate that elevated OPN expression in SSc lung tissue is enriched in macrophages, partially overlapping with CCL18 expression. Serum OPN is elevated in SSc patients with interstitial lung disease (ILD) and prognosticates future lung function deterioration in SSc cohorts. Serum OPN levels decrease following tocilizumab (monoclonal anti-IL-6 receptor) treatment, confirming the connection between IL-6 and OPN in SSc patients. Collectively, these data suggest a plausible link between autoantibodies and lung fibrosis progression, where circulating OPN serves as a systemic proxy for IC-driven profibrotic macrophage activity, highlighting its potential as a promising biomarker in SSc ILD.

Paper PDF

This paper's license is marked as closed access or non-commercial and cannot be viewed on ResearchHub. Visit the paper's external site.