Abstract
Cytokines are key regulators of physiological inflammatory responses, while aberrant cytokine expression contributes to pathogenesis of autoimmune diseases. We noted increased IL-6 levels in human and murine epidermolysis bullosa acquisita (EBA), a prototypic organ-specific autoimmune bullous dermatoses (AIBD) induced by autoantibodies to type VII collagen (COL7). In contrast to rheumatoid arthritis, blockade of IL-6 led to strikingly enhanced experimental EBA, while treatment with recombinant IL-6 was protective. This was due to classical IL-6 signalling and independent of IL-6 trans-signalling, as treatment of mice with sgp130Fc had no impact on EBA manifestation. Induction of EBA in mice led to increased IL-1ra levels in skin and serum, while blockade of IL-6 completely inhibited IL-1ra expression induced by autoantibodies to COL7. In line, treatment of mice with EBA with recombinant IL-6 induced IL-1ra concentrations exceeding those of untreated animals with EBA, and IL-1ra (anakinra) administration significantly impaired experimental EBA induction. We here identified a novel anti-inflammatory pathway in an organ-specific autoimmune disease. Modulation of this IL-1ra pathway by classical IL-6 signalling demonstrates anti-inflammatory and protective activities of IL-6 in vivo.
| Original language | English |
|---|---|
| Journal | Journal of Autoimmunity |
| Volume | 40 |
| Issue number | 1 |
| Pages (from-to) | 74-85 |
| Number of pages | 12 |
| ISSN | 0896-8411 |
| DOIs | |
| Publication status | Published - 01.02.2013 |
Funding
We thank Prof. Cem Gabay and Dr. Celine Lamacchia (Division of Rheumatology, University Hospitals of Geneva, Geneva, Switzerland) for critical discussion and providing primer sequences for IL-1ra. This study was supported by the following grants: Excellence Cluster “Inflammation at Interfaces” ( EXC306/1 ), Graduiertenkolleg “Modulation of Autoimmunity” ( GRK1727/1 ) and LU877/5-1 , all provided by the Deutsche Forschungsgemeinschaft , as well as Focus Program “Autoimmunity” at the University of Lübeck and the Doktor Robert-Pfleger Foundation . The contribution of JS and SRJ was supported by the Deutsche Forschungsgemeinschaft (SFB877, projects A1, A2). Appendix A