The Novel Cytokine Interleukin-41/Meteorin-like Is Reduced in Diffuse Systemic Sclerosis.

Area of Science:

• Immunology
• Rheumatology
• Cell Biology

Background:

• Systemic sclerosis (SSc) is an autoimmune disease characterized by vascular issues, inflammation, and fibrosis.
• Fibroblast activation into myofibroblasts is central to SSc, influenced by cytokines.
• Interleukin-41 (IL-41), a cytokine with immunomodulatory roles, is increasingly recognized beyond its adipokine origins.

Purpose of the Study:

• To investigate the role of IL-41 in systemic sclerosis.
• To quantify circulating IL-41 levels and its expression in SSc skin biopsies.
• To explore the relationship between IL-41, fibroblast activation, and related signaling pathways in SSc.

Main Methods:

• Measurement of circulating IL-41 levels in SSc patients and controls.
• Assessment of IL-41 expression in skin biopsies from SSc patients.
• Quantification of mammalian target of rapamycin (mTOR) levels in SSc skin biopsies.

Main Results:

• Significantly reduced circulating levels of IL-41 were observed in patients with diffuse SSc.
• IL-41 expression was also diminished in the skin of SSc patients.
• Elevated levels of mTOR, a potential downstream target of IL-41, were detected in SSc skin.

Conclusions:

• IL-41 levels are decreased in systemic sclerosis, suggesting a potential role in the disease.
• Reduced IL-41 may contribute to fibroblast activation and fibrosis in SSc.
• IL-41 is proposed as a potential antifibrotic cytokine whose reduction facilitates fibroblast activation in SSc.