Mutated cylindromatosis gene affects the functional state of dendritic cells

Abstract

SwedenCylindromatosis gene (CYLD) is a ubiquitously expressed deubiquitinating enzyme, which interacts with members of the NF-jB signaling pathway and attenuates NF-jB and JNK signaling. Here, we report that DC derived from transgenic mice, which solely express a naturally occurring CYLD isoform (CYLD ex7/8 ), display a higher content of nuclear RelB and express elevated levels of NF-jB family members as well as of known NF-jB-target genes comprising costimulatory molecules and pro-inflammatory cytokines, as compared with WT DC. Accordingly, unstimulated CYLD ex7/8 DC exhibited a significantly higher primary allogenic T-cell stimulatory capacity than WT DC and exerted no tolerogenic activity. Transduction of unstimulated CYLD ex7/8 DC with relB-specific shRNA reduced their T-cell stimulatory capacity. Treatment with the synthetic glucocorticoid dexamethasone known to inhibit NF-jB and AP-1 activity reverted the pro-immunogenic phenotype and function of CYLD ex7/8 DC and re-established their tolerogenic function. DC derived from CYLD knockout mice showed no functional alterations compared with WT DC. Therefore, although complete loss of CYLD may be compensated for by other endogenous NF-jB inhibitors, CYLD ex7/8 acts in a dominant negative manner. Our findings raise the question of whether genetic defects associated with increased NF-jB activity may result in disturbed maintenance of peripheral tolerance.

Differential gene expression analysis identifies murine Cacnb3 as strongly upregulated in distinct dendritic cell populations upon stimulation

“…In contrast, Fscn1 was found upregulated in both SP37A3 cells (see Fig. 1B; and BM-DCs (Bros et al, 2010) in response to stimulation, and thereby represents a DC relevant gene commonly upregulated in different DC subpopulations.…”

“…Western blot analysis was performed as previously described (Bros et al, 2010) using the following antibodies: rabbit polyclonal antimouse Cacnb3 (ab79264; Abcam, Cambridge, UK), which recognizes total Cacnb3, HRP-conjugated donkey polyclonal anti-rabbit (sc-2313, Santa Cruz, CA), and HRP-conjugated polyclonal rabbit anti-β-tubulin (ab21058, Abcam).…”

CYLD-Mediated Signaling and Diseases

“…This downregulates inflammation and, thusly, activation of the immune system. This is in addition to indications that NF-B, which enhances HIV Long Terminal Repeat transcription by NF-kB/NFAT sites that flank the LTR, is able to drive transcription of viral LTRs when CYLD action was removed in T cell lines, indicating that at least some viral strategies include control of NF-kB and CYLD may be the key to stopping the hijacking of NF-kB in these cases [70]. CYLD impairs production of fibrin in Listeria infection in mice by inhibiting NF-kB-mediated activation of IL-6 production and IL-6’s activation of the STAT3 pathway that leads to fibrosis [71].…”

Genome-wide associated loci influencing interleukin (IL)-10, IL-1Ra, and IL-6 levels in African Americans

“…CYLD is a deubiquitinating enzyme which attenuates NF-κB and c-Jun NH 2 -terminal kinase (JNK) signaling. In transgenic mouse CYLD ex7/8 protein increased expression of mouse Il10 mRNA in cultured bone-marrow-derived dendritic cells (Bros et al 2010). Further studies are needed to understand the functional roles of the genome-wide associated SNPs in PMS1 , IPO7 (encodes a protein that mediates nuclear import of proteins with a classical nuclear localization signal), YWHA (encodes a protein that is a member of a highly conserved protein family that mediates signal transduction by binding to phosphoserine-containing proteins), and CDYL2 (encodes a protein involved in catalytic activity and protein binding).…”