Engagement of Fas on macrophages modulates poly I:C induced cytokine production with specific enhancement of IP-10
Lyons, Caitríona M.
Fanning, Liam J.
Houston, Aileen M.
Brint, Elizabeth K.
Public Library of Science
Viral double-stranded RNA (dsRNA) is recognised by pathogen recognition receptors such as Toll-Like Receptor 3 (TLR3) and retinoic acid inducible gene-I (RIG-I), and results in cytokine and interferon production. Fas, a well characterised death receptor, has recently been shown to play a role in the inflammatory response. In this study we investigated the role of Fas in the anti-viral immune response. Stimulation of Fas on macrophages did not induce significant cytokine production. However, activation of Fas modified the response of macrophages to the viral dsRNA analogue poly I:C. In particular, poly I:C-induced IP-10 production was significantly enhanced. A similar augmentation of IP-10 by Fas was observed following stimulation with both poly A:U and Sendai virus. Fas activation suppressed poly I:C-induced phosphorylation of the MAP kinases p38 and JNK, while overexpression of the Fas adaptor protein, Fas-associated protein with death domain (FADD), activated AP-1 and inhibited poly I:C-induced IP-10 production. Consistent with an inhibitory role for AP-1 in IP-10 production, mutation of the AP-1 binding site on the IP-10 promoter resulted in augmented poly I:C-induced IP-10. These results demonstrate that engagement of the Fas receptor plays a role in modifying the innate immune response to viral RNA.
NF-kappaB , Domain-containing protein , Hepatitis C virus , RIG-I , Death domain , Induced apoptosis , Infected cells , Activation , Fadd , IL-1 beta
Lyons C, Fernandes P, Fanning LJ, Houston A, Brint E (2015) Engagement of Fas on Macrophages Modulates Poly I:C Induced Cytokine Production with Specific Enhancement of IP-10. PLoS ONE 10(4): e0123635. doi:10.1371/journal.pone.0123635