| First Author | Garbers C | Year | 2011 |
| Journal | J Biol Chem | Volume | 286 |
| Issue | 50 | Pages | 42959-70 |
| PubMed ID | 21990364 | Mgi Jnum | J:180703 |
| Mgi Id | MGI:5306863 | Doi | 10.1074/jbc.M111.295758 |
| Citation | Garbers C, et al. (2011) Inhibition of classic signaling is a novel function of soluble glycoprotein 130 (sgp130), which is controlled by the ratio of interleukin 6 and soluble interleukin 6 receptor. J Biol Chem 286(50):42959-70 |
| abstractText | IL-6 trans-signaling via the soluble IL-6 receptor (sIL-6R) plays a critical role in chronic inflammation and cancer. Soluble gp130 (sgp130) specifically inhibits IL-6 trans-signaling but was described to not interfere with classic signaling via the membrane-bound IL-6R. Physiological and most pathophysiological conditions are characterized by a molar excess of serum sIL-6R over IL-6 characterized by free IL-6 and IL-6 found in IL-6.sIL-6R complexes allowing both classic and trans-signaling. Surprisingly, under these conditions, sgp130 was able to trap all free IL-6 molecules in IL-6.sIL-6R.sgp130 complexes, resulting in inhibition of classic signaling. Because a significant fraction of IL-6 molecules did not form complexes with sIL-6R, our results demonstrate that compared with the anti-IL-6R antibody tocilizumab or the anti-trans-signaling monoclonal antibody 25F10, much lower concentrations of the dimeric sgp130Fc were sufficient to block trans-signaling. In vivo, sgp130Fc blocked IL-6 signaling in the colon but not in liver and lung, indicating that the colon is a prominent target of IL-6 trans-signaling. Our results point to a so far unanticipated role of sgp130 in the blockade of classic signaling and indicate that in vivo only low therapeutic concentrations of sgp130Fc guarantee blockade of IL-6 trans-signaling without affecting IL-6 classic signaling. |
