Search Results (7)

Protocadherin-7 (Pcdh7) is a member of the protocadherin family, a subgroup of the cadherin superfamily. We previously demonstrated that Pcdh7 functions as a signaling receptor in osteoclast differentiation. In this study, we investigated the potential gene regulatory role of Pcdh7 in this process and identified Pyrin domain-containing protein 3 (Pydc3) as a key mediator of Pcdh7-mediated regulation of osteoclast differentiation. Differential gene expression analysis comparing wild-type (Pcdh7^+/+) and Pcdh7-deficient (Pcdh7^−/−) cells revealed a significant upregulation of Pydc3 in Pcdh7^−/− cells. RNAi-mediated knockdown of Pydc3 rescued the impaired osteoclast differentiation in Pcdh7^−/− cells, whereas overexpression of Pydc3 suppressed osteoclast differentiation in Pcdh7^+/+ cells, suggesting that Pydc3 negatively regulates osteoclast differentiation. Additionally, Pcdh7^−/− cells showed elevated expression of interferon response genes and increased production of interferon-β (IFN-β). Neutralization of IFN-β signaling using anti-IFN-β and/or anti-interferon alpha and beta receptor 1 (IFNAR1) antibodies significantly restored osteoclast differentiation in Pcdh7^−/− cells. Collectively, these findings uncover a novel role for Pcdh7 in osteoclast differentiation through regulation of Pydc3 expression and IFN-β production. Full article

Cell culture-based influenza vaccines exhibit comparable safety and immunogenicity to traditional egg-based vaccines. However, improving viral yield remains a key challenge in optimizing cell culture-based production systems. Madin–Darby canine kidney (MDCK) cells, the predominant cell line for influenza vaccine production, inherently activate interferon (IFN)-mediated antiviral defenses that restrict viral replication. To overcome this limitation, we employed CRISPR/Cas9 gene-editing technology to generate an IFN alpha/beta receptor subunit 1 (IFNAR1)-knockout (KO) adherent MDCK cell line. Viral titer analysis demonstrated significant enhancements in the yield of multiple vaccine strains (H1N1, H3N2, and type B) in IFNAR1-KO cells compared to wild-type (WT) cells. Transcriptomic profiling revealed marked downregulation of key interferon-stimulated genes (ISGs)—including OAS, MX2, and ISG15—within the IFNAR1-KO cells, indicating a persistent suppression of antiviral responses that established a more permissive microenvironment for influenza virus replication. Collectively, the engineered IFNAR1-KO cell line provides a valuable tool for influenza virus research and a promising strategy for optimizing large-scale MDCK cell cultures to enhance vaccine production efficiency. Full article

Background: Ammonia (NH₃), a harmful gas, reduces livestock productivity, threatens their health, and causes economic losses. Luteolin (Lut), an anti-inflammatory flavonoid, may counteract these effects. Methods: Our study explored luteolin’s protective mechanisms on chicken splenic lymphocytes under ammonia stress using a simulation model and four-dimensional fast data-independent acquisition (4D-FastDIA) proteomics. We identified 316 proteins, with 69 related to ammonia’s negative effects and 247 to Lut’s protection. Thirty differentially expressed proteins (DEPs) were common to both groups, with 27 showing counter-regulation with Lut. Results: Gene Ontology (GO) analysis showed DEPs enriched in molecular responses to interferons and the negative regulation of immune responses, mainly located extracellularly. Molecular function analysis revealed DEPs in antigen binding and synthase activity. Kyoto Encyclopedia of Genes and Genomes (KEGG) analysis linked DEPs to pathways like estrogen signaling, NOD-like receptor signaling, cytokine–cytokine receptor interaction, and JAK-STAT signaling. The quantitative real-time polymerase chain reaction (qRT-PCR) results indicated that the mRNA levels of Interferon Alpha and Beta Receptor subunit 2 (IFNAR2) and Signal Transducer and Activator of Transcription 1 (STAT1) were trending downward. This observation was in strong agreement with the downregulation noted in the proteomics analysis. Conclusions: Lut’s protective role against ammonia’s adverse effects on chicken splenic lymphocytes is linked to the modulation of key signaling pathways, offering insights for further research on treating ammonia exposure with Lut. Full article

The treatment of pancreatic ductal adenocarcinoma (PDAC) is an unmet challenge, with the median overall survival rate remaining less than a year, even with the use of FOLFIRINOX-based therapies. This study analyzed archived macrophage-associated mRNA expression using datasets deposited in the UCSC Xena web platform to compare normal pancreatic tissue and PDAC tumor samples. The TGFB2 gene exhibited low mRNA expression levels in normal tissue, with less than one TPM. In contrast, in tumor tissue, TGFB2 expression levels exhibited a 7.9-fold increase in mRNA expression relative to normal tissue (p < 0.0001). Additionally, components of the type-I interferon signaling pathway exhibited significant upregulation of mRNA levels in tumor tissue, including Interferon alpha/beta receptor 1 (IFNAR1; 3.4-fold increase, p < 0.0001), Interferon regulatory factor 9 (IRF9; 4.2-fold increase, p < 0.0001), Signal transducer and activator of transcription 1 (STAT1; 7.1-fold increase, p < 0.0001), and Interferon Alpha Inducible Protein 27 (IFI27; 66.3-fold increase, p < 0.0001). We also utilized TCGA datasets deposited in cBioportal and KMplotter to relate mRNA expression levels to overall survival outcomes. These increased levels of mRNA expression were found to be prognostically significant, whereby patients with high expression levels of either TGFB2, IRF9, or IFI27 showed median OS times ranging from 16 to 20 months (p < 0.01 compared to 72 months for patients with low levels of expression for both TGFB2 and either IRF9 or IFI27). Examination of the KMplotter database determined the prognostic impact of TGFB2 mRNA expression levels by comparing patients expressing high versus low levels of TGFB2 (50th percentile cut-off) in low macrophage TME. In TME with low macrophage levels, patients with high levels of TGFB2 mRNA exhibited significantly shorter OS outcomes than patients with low TGFB2 mRNA levels (Median OS of 15.3 versus 72.7 months, p < 0.0001). Furthermore, multivariate Cox regression models were applied to control for age at diagnosis. Nine genes exhibited significant increases in hazard ratios for TGFB2 mRNA expression, marker gene mRNA expression, and a significant interaction term between TGFB2 and marker gene expression (mRNA for markers: C1QA, CD74, HLA-DQB1, HLA-DRB1, HLA-F, IFI27, IRF9, LGALS9, MARCO). The results of our study suggest that a combination of pharmacological tools can be used in treating PDAC patients, targeting both TGFB2 and the components of the type-I interferon signaling pathway. The significant statistical interaction between TGFB2 and the nine marker genes suggests that TGFB2 is a negative prognostic indicator at low levels of the IFN-I activated genes and TAM marker expression, including the immune checkpoint LGALS9 (upregulated 16.5-fold in tumor tissue; p < 0.0001). Full article

Type I interferon (IFN-I) signaling has been shown to be upregulated in systemic sclerosis (SSc). Dysregulated B-cell functions, including antigen presentation, as well as antibody and cytokine production, all of which may be affected by IFN-I signaling, play an important role in the pathogenesis of the disease. We investigated the IFN-I signature in 71 patients with the more severe form of the disease, diffuse cutaneous SSc (dcSSc), and 33 healthy controls (HCs). Activation via Toll-like receptors (TLRs) can influence the IFN-I signaling cascade; thus, we analyzed the effects of the TLR homologue CD180 ligation on the IFN-I signature in B cells. CD180 stimulation augmented the phosphorylation of signal transducer and activator of transcription 1 (STAT1) in dcSSc B cells (p = 0.0123). The expression of IFN-I receptor (IFNAR1) in non-switched memory B cells producing natural autoantibodies was elevated in dcSSc (p = 0.0109), which was enhanced following anti-CD180 antibody treatment (p = 0.0125). Autoantibodies to IFN-Is (IFN-alpha and omega) correlated (dcSSc p = 0.0003, HC p = 0.0192) and were present at similar levels in B cells from dcSSc and HC, suggesting their regulatory role as natural autoantibodies. It can be concluded that factors other than IFN-alpha may contribute to the elevated IFN-I signature of dcSSc B cells, and one possible candidate is B-cell activation via CD180. Full article

ADAR (adenosine deaminase acting on RNA) catalyzes the deamination of adenosine to generate inosine, through its binding to double-stranded RNA (dsRNA), a phenomenon known as RNA editing. One of the functions of ADAR1 is suppressing the type I interferon (IFN) response, but its mechanism in gastric cancer is not clearly understood. We analyzed changes in RNA editing and IFN signaling in ADAR1-depleted gastric cancer cells, to clarify how ADAR1 regulates IFN signaling. Interestingly, we observed a dramatic increase in the protein level of signal transducer and activator of transcription 1 (STAT1) and interferon regulatory factor 9 (IRF9) upon ADAR1 knockdown, in the absence of type I or type II IFN treatment. However, there were no changes in protein expression or localization of the mitochondrial antiviral signaling protein (MAVS) and interferon alpha and beta-receptor subunit 2 (IFNAR2), the two known mediators of IFN production. Instead, we found that miR-302a-3p binds to the untranslated region (UTR) of IRF9 and regulate its expression. The treatment of ADAR1-depleted AGS cells with an miR-302a mimic successfully restored IRF9 as well as STAT1 protein level. Hence, our results suggest that ADAR1 regulates IFN signaling in gastric cancer through the suppression of STAT1 and IRF9 via miR-302a, which is independent from the RNA editing of known IFN production pathway. Full article

Hepatitis C virus (HCV) infection triggers autophagy processes, which help clear out the dysfunctional viral and cellular components that would otherwise inhibit the virus replication. Increased cellular autophagy may kill the infected cell and terminate the infection without proper regulation. The mechanism of autophagy regulation during liver disease progression in HCV infection is unclear. The autophagy research has gained a lot of attention recently since autophagy impairment is associated with the development of hepatocellular carcinoma (HCC). Macroautophagy, microautophagy, and chaperone-mediated autophagy (CMA) are three autophagy processes involved in the lysosomal degradation and extracellular release of cytosolic cargoes under excessive stress. Autophagy processes compensate for each other during extreme endoplasmic reticulum (ER) stress to promote host and microbe survival as well as HCC development in the highly stressed microenvironment of the cirrhotic liver. This review describes the molecular details of how excessive cellular stress generated during HCV infection activates CMA to improve cell survival. The pathological implications of stress-related CMA activation resulting in the loss of hepatic innate immunity and tumor suppressors, which are most often observed among cirrhotic patients with HCC, are discussed. The oncogenic cell programming through autophagy regulation initiated by a cytoplasmic virus may facilitate our understanding of HCC mechanisms related to non-viral etiologies and metabolic conditions such as uncontrolled type II diabetes. We propose that a better understanding of how excessive cellular stress leads to cancer through autophagy modulation may allow therapeutic development and early detection of HCC. Full article