Publication in detail

Genes and immunity 2012 Apr 26. doi: 10.1038/gene.2012.10. [Epub ahead of print]

Unique contribution of IRF-5-Ikaros axis to the B-cell IgG2a response.

Fang, CM; Roy, S; Nielsen, E; Paul, M; Maul, R; Paun, A; Koentgen, F; Raval, FM; Szomolanyi-Tsuda, E; Pitha, PM

Department of Biology, Johns Hopkins University, Baltimore, MD 21218, USA.

IRF-5 is a transcription factor activated by toll like receptor (TLR)7 and TLR9 during innate immune responses. IRF-5 activates not only Type I IFN, but also inflammatory cytokines. Most importantly, a genetic variation in the IRF-5 gene shows a strong association with autoimmune diseases such as Lupus. Here, we report that IRF5-deficient mice have attenuated IgG2a/c responses to T-cell-dependent and -independent antigens and to polyoma virus infection. This defect is due to the intrinsic deletion of IRF-5 in B cells, as SCID mice reconstituted with Irf5-/- B cells show a decrease in IgG2a/c expression after viral infection compared with mice that received wild-type B cells. Irf5-/-B cells in vitro have diminished TLR and cytokine-induced class switching to IgG2a/c. Addressing the molecular mechanism, we show that IRF-5 regulates IgG2a/c expression by decreasing Ikaros expression; reconstitution of IRF-5 in Irf5-/- B cells downregulates Ikaros levels and increases switching to IgG2a/c. The IRF site in ikzf1 promoter binds IRF-5, IRF-4 and IRF-8. We show that IRF-8 but not IRF-4 activates the ikzf1 promoter, and IRF-5 inhibits the transcriptional activity of IRF-8. Collectively, these results identify the IRF-5-Ikaros axis as a critical modulator of IgG2a/c class switching.Genes and Immunity advance online publication, 26 April 2012; doi:10.1038/gene.2012.10.

ยป Online Version

Proven Track Record

The team at Ozgene has over two decades of experience creating customised knockout and knock-in mice for pivotal medical research globally. Over 400 scientific publications are based on research using Ozgene mice.

Go to Publications

Global Client Base

Ozgene generates genetically customised mice for researchers around the world. Ozgene mice can be found in 31 different countries on 5 continents from small academic institutions to multinational pharmaceutical companies.

See Client Papers

Lean Management

Ozgene is applying Lean Management principles to deliver the highest quality services and shortest lead times to our customers. The implementation of Lean Culture has already seen an improvement in our processes and timelines.

Read More