BRD4 contributes to the cytokine-induced acquisition of an IL-13RA2-positive inflammatory fibroblast phenotype

Upadacitinib effectively suppresses IL13RA2 expression in primary human intestinal fibroblasts derived from Crohn's disease tissue.

Interleukin-13 receptor alpha 2 (IL13RA2) is highly expressed in intestinal inflammation-associated fibroblasts (IAFs) and is associated with anti-tumor necrosis factor alpha (TNF-α) therapy resistance in inflammatory bowel disease (IBD). Because IL13RA2 inhibition ameliorates experimental colitis in mice, we investigated IL13RA2 regulation in Crohn's disease (CD)-derived primary human intestinal fibroblasts (phIFs) and the effect of anti-TNF-α infliximab and the Janus Kinase (JAK)1 inhibitor upadacitinib. Nineteen independent phIF cultures were established from CD surgical tissue, either from full tissue pieces (explant) or cell suspensions (suspension). phIFs were exposed to IL13, upadacitinib, infliximab, and/or signal transducer and activator of transcription (STAT)3/6 inhibitors. Cellular responses were assessed using viability assays, qRT-PCR, Western blotting and fluorescence microscopy. Suspension-derived phIFs exhibited higher basal IL13RA2 expression than explant-derived phIFs. IL13 strongly enhanced IL13RA2 mRNA and protein levels in phIFs. Upadacitinib effectively suppressed basal and IL13-induced IL13RA2 expression, without affecting phIF viability or proliferation. Infliximab did not reduce IL13-induced IL13RA2 expression. IL13 induced both STAT3 and STAT6 phosphorylation and STAT6 inhibition efficiently suppressed IL13-induced IL13RA2 expression, mirroring the effect of upadacitinib. These results reveal that CD-derived phIFs show marked heterogeneity in basal IL13RA2 expression, which is strongly induced by IL13 and associated with JAK1-STAT6 pathway activation, both of which are effectively suppressed by upadacitinib. This direct effect of JAK inhibition on IL13RA2 expression may contribute to its therapeutic effect in IBD.

AFF3 regulates M5‑induced psoriatic inflammation in keratinocytes through the MAPK signaling pathway

OTUD5 Maintains STAT1/2 Stability and Promotes IFNγ-driven Intestinal Inflammation.

Inflammatory bowel disease (IBD) is characterized by unresolved mucosal inflammation driven mainly by TNFα and/or IFNγ. While anti-TNFα biologics are a clinical mainstay, therapeutic resistance remains a significant hurdle. The molecular mechanisms that sustain inflammation in anti-TNFα non-responders are not fully understood. In human colon biopsies, we identified significant upregulation of the deubiquitinase OTUD5 in non-responders compared to responders, suggesting its involvement in therapy resistance. Using an intestinal epithelial cell (IEC)-specific Otud5 knockout mouse model, we show that Otud5 deficiency significantly alleviated the IFNγ-dependent colitis induced by dextran sulfate sodium (DSS), as evidenced by reduced weight loss and diminished infiltration of Ly6C+ inflammatory monocytes. Mechanistically, IFNγ induces OTUD5 expression through a non-transcriptional mechanism; in turn, OTUD5 stabilizes STAT1 and STAT2 by preventing their ubiquitination and subsequent degradation. This sustains IFNγ-ISGF3 signaling, which directly drives the expression of CCL8, a critical chemokine for monocyte recruitment. Targeting this pathway with a newly identified small-molecule inhibitor, CT1170, which exhibits potent activity against OTUD5, blocked the IFNγ-ISGF3-CCL8 axis, halted colitis progression, and suppressed colitis-elicited tumorigenesis. These findings were validated in human IBD organoids, where CT1170 effectively disrupted IFNγ-driven inflammatory signaling.

Transcriptomic profiling reveals selective attenuation of interferon-associated inflammatory signaling and induction of metallothioneins by a zinc-containing oral rinse

Background Oral stromal and epithelial cells contribute to mucosal inflammation through cytokine-induced chemokine production. Essential oil-containing mouth rinses are widely used as adjuncts to oral hygiene, but whether zinc-containing formulations directly modulate host inflammatory signaling remains unclear. This study investigated the effects of a zinc-containing Listerine® formulation on IL-1β/TNF-α-induced inflammatory responses in human oral cells. Methods Primary human gingival fibroblasts were stimulated with IL-1β/TNF-α in the presence or absence of Listerine®. Transcriptional responses were analyzed by RNA sequencing and validated by quantitative PCR and immunoassays. HSC2 epithelial cells were used to assess selected responses across oral cell types. Phospho-STAT1 immunostaining evaluated canonical STAT1 activation, and ICP–MS determined trace-element composition. Results IL-1β/TNF-α induced a broad inflammatory transcriptional program characterized by chemokines, NF-κB-associated mediators, and interferon-associated genes. Listerine® attenuated this response, with strongest effects on CXCL10, CXCL11, IFIT family members, GBP family members, and OASL, whereas classical NF-κB-associated chemokines such as CXCL1, CXCL2, and CXCL8 were less affected. Listerine® also induced a zinc-responsive stress-adaptation signature dominated by metallothioneins. ICP–MS analysis confirmed the presence of zinc in Listerine®, and zinc alone partially reproduced the suppression of CXCL10. In contrast, individual essential oil constituents failed to recapitulate the anti-inflammatory effects of the complete formulation. Notably, Listerine® did not prevent IFN-γ-induced STAT1 phosphorylation, indicating that suppression of interferon-associated genes was not due to general blockade of canonical STAT1 activation. Conclusion These findings identify a previously unrecognized host-modulatory activity of a zinc-containing Listerine® formulation characterized by selective attenuation of interferon-associated inflammatory transcription together with induction of a zinc-responsive metallothionein program.

Immunosuppressive effects of voclosporin in inflammatory bowel disease through targeted inhibition of SLP-76 and metabolic reprogramming.

The adaptor protein SLP-76 plays a critical role in T-cell receptor signaling and immune activation, yet its relevance in inflammatory bowel disease (IBD) remains unclear. Although calcineurin inhibitors such as cyclosporine A (CsA) are used in severe ulcerative colitis, voclosporin (VCS), a novel calcineurin inhibitor approved for lupus nephritis, has not been systematically evaluated in IBD. We investigated whether SLP-76 is dysregulated in IBD and can be modulated by calcineurin inhibitors. Expression of SLP-76 was analyzed in intestinal biopsy specimens of patients with ulcerative colitis and Crohn's disease using quantitative PCR (qPCR) and immunofluorescence. PBMCs from patients with IBD and healthy control participants were stimulated with anti-CD3/CD28 in the presence or absence of CsA or VCS. Downstream effects were analyzed by qPCR, flow cytometry, cytokine, and metabolic profiling. SLP-76 was significantly upregulated in inflamed intestinal tissue and correlated significantly with histological inflammation. No differences were observed in PBMCs between control participants and patients with IBD. Both calcineurin inhibitors reduced phosphorylation of SLP-76 and impaired downstream signaling in CD4+ and CD8+ T cells. However, only VCS significantly decreased total SLP-76 protein and suppressed expression of the early activation marker CD69 and Ras-MAPL signaling. Metabolomic profiling showed that VCS induced distinct metabolic changes compared with CsA. Our findings highlight SLP-76 as a potential immunoregulatory target in IBD and suggest that VCS exerts broader immunosuppressive effects than CsA, supporting its repurposing as a therapeutic strategy.

Numb Mediates IL-1β/TGF-β1-Driven Inflammation-Fibrosis Coupling in Idiopathic Pulmonary Fibrosis.

BACKGROUND In idiopathic pulmonary fibrosis (IPF), inflammatory signaling and fibrotic remodeling often coexist, yet the mechanism linking these processes remains unclear. Numb, a cell fate determinant protein, has been implicated in tissue remodeling but its role in inflammation - fibrosis coupling is not well defined. METHODS Public transcriptomic datasets were analyzed to assess NUMB expression patterns and associated pathways. A bleomycin (BLM)-induced mouse model was used for in vivo validation. In vitro, MRC-5 fibroblasts were stimulated with IL-1β and TGF-β1, alone or in combination, followed by Numb siRNA intervention. Cell viability, migration, cytokine secretion, and fibrosis-related protein expression were evaluated. RESULTS Transcriptomic analysis showed a non-significant but consistent upward trend of NUMB in IPF tissues (p = .18), with pathway-level enrichment in inflammatory and extracellular matrix processes. In BLM-treated mice, IL-1β and TGF-β1 levels were significantly increased (both p < .001), accompanied by upregulation of Numb (p < .05), α-SMA, and Collagen I (both p < .001). In vitro, IL-1β and TGF-β1 synergistically enhanced cell viability and migration (both p < .001), as well as protein expression (p < .001). Numb silencing reduced cytokine secretion (p < .001), cell activation (p < .05-0.001), and fibrosis-related protein expression (p < .001). CONCLUSION Numb participates in coordinating inflammatory and fibrotic responses in IPF and may act as a regulatory mediator in inflammation - fibrosis coupling.