Th-17 cytokines and interstitial lung involvement in systemic sclerosis

Area of Science:

• Immunology
• Pulmonology
• Rheumatology

Background:

• Systemic sclerosis (SSc) presents with limited or diffuse phenotypes, each associated with distinct pulmonary complications.
• Diffuse SSc commonly involves interstitial lung disease (ILD), while the limited phenotype is linked to pulmonary arterial hypertension.
• The role of Th17-related cytokines in the pathogenesis of ILD in SSc requires further elucidation.

Purpose of the Study:

• To investigate the association between Th17-related cytokines in exhaled breath condensate (EBC) and serum with ILD in diffuse SSc patients.
• To compare cytokine levels between limited and diffuse SSc phenotypes and healthy controls.
• To explore correlations between cytokine levels and measures of lung function and ILD severity.

Main Methods:

• Measurement of Th17-related cytokines in EBC and serum from patients with limited and diffuse SSc and healthy controls.
• Assessment of ILD severity using thoracic CT-scan scores.
• Evaluation of lung function including carbon monoxide diffusing capacity and vital capacity.

Main Results:

• Significantly higher EBC cytokine levels and most serum cytokine levels were observed in SSc patients compared to controls.
• Elevated EBC Th17 cytokines and serum IL-10 and TNF-α levels were found in diffuse SSc compared to limited SSc.
• ILD CT-scan scores correlated with EBC IL-1 beta and serum IL-23, TNF-α, and IL-10. Lung function parameters showed inverse relationships with several measured cytokines.

Conclusions:

• A significant association exists between Th17-related cytokines (measured in EBC and serum) and interstitial lung involvement in diffuse SSc.
• These findings underscore the potential therapeutic importance of targeting Th17 cytokines for treating lung fibrosis in SSc.
• Further research into Th17-mediated pathways could lead to novel treatment strategies for SSc-related ILD.