Interferons and systemic sclerosis: correlation between interferon gamma and interferon-lambda 1 (IL-29)

Abstract

Background: Interferon (IFN)-λ1 is a newly described cytokine, member of type III interferons family, which is known for its antiviral, anti-proliferative and antitumor activity. Recent studies indicated that this cytokine has also immune-regulatory function, but its role in the pathogenesis of autoimmune diseases is not established yet. We evaluated serum levels of IFN-λ1 in systemic sclerosis (SSc) patients and healthy controls and its association with IFN-γ and clinical manifestations. Methods: IFN-λ1 and IFN-γ serum levels were measured by ELISA from 52 patients with SSc and 53 healthy controls. Association of cytokines serum levels was sought with clinical parameters. Results: IFN-λ1 and IFN-γ levels in SSc patients were significantly higher than those in healthy individuals (24.82 ± 8.78 and 11.04 ± 3.04 pg/ml, p < 0.0001; 34.11 ± 8.11 and 10.73 ± 2.77 pg/ml, p < 0.0001, respectively). We found a positive correlation between IFN-λ1 and IFN-γ levels in SSc patients (p = 0.0103, r = 0.3526). IFN-γ levels were associated with muscle involvement (p = 0.0483). Conclusion: We first showed raised IFN-λ1 levels in SSc patients. Furthermore, we found a correlation between IFN-λ1 and IFN-γ levels and an association between IFN-γ and myositis. Additional in vitro and in vivo studies are needed to understand IFN-λ1 role in SSc.

• Cytokine
• interleukin-29
• interferon-lambda1
• interferon-gamma
• scleroderma

Acknowledgements

We thank the Brazilian National Research Council, the Research Foundation of Pernambuco State and the National Institute for Science and Technology in Pharmaceutical Innovation.

Declaration of interest

The authors declare that there are no conflicts of interest.