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BACKGROUND: Individuals with type 2 diabetes are three times more likely to develop active tuberculosis (TB) after infection compared to those without diabetes. The mechanisms behind this increased risk remain unclear but may involve abnormal immune responses, including enhanced pro-inflammatory activity and altered cell phenotypes, particularly involving type-1 and type-2 interferon responses. METHOD: This study used flow cytometry and ELISA to assess type-1 and type-2 interferon production in peripheral blood mononuclear cells (PBMCs) from healthy BCG-vaccinated donors exposed to live Mycobacterium bovis (BCG). The expression of six type-1 interferon-inducible genes was evaluated in PBMC and whole blood cultures using quantitative real-time RT-PCR. Additionally, plasma IFNα/γ levels in tuberculosis patients with and without type II diabetes (n = 120) were measured.Results revealed that IFN-α was undetectable in PBMCs cultured with BCG, although six IFN-α-responsive genes were notably upregulated. IFN-γ levels were significantly elevated in TB-only and TB-pre-DM patients, but not in those with both TB and diabetes. Plasma IFN-α levels remained consistently low across all patient groups, with no significant differences detected.These findings suggest that IFN-γ responses vary among TB patients depending on their diabetes status. IFN-α is not significantly upregulated in response to BCG stimulation in PBMCs. This highlights the complexity of the immune response in TB patients with type II diabetes and suggests a potential role of interferon pathways in their increased susceptibility to TB.

We previously observed increased levels of adenosine‐deaminase‐acting‐on‐dsRNA (Adar)‐dependent RNA editing during mesothelioma development in mice exposed to asbestos. The aim of this study was to characterize and assess the role of ADAR‐dependent RNA editing in mesothelioma. We found that tumors and mesothelioma primary cultures have higher ADAR‐mediated RNA editing compared to mesothelial cells. Unsupervised clustering of editing in different genomic regions revealed heterogeneity between tumor samples as well as mesothelioma primary cultures. ADAR2 expression levels are higher in BRCA1‐associated protein 1 wild‐type tumors, with corresponding changes in RNA editing in transcripts and 3'UTR. ADAR2 knockdown and rescue models indicated a role in cell proliferation, altered cell cycle, increased sensitivity to antifolate treatment, and type‐1 interferon signaling upregulation, leading to changes in the microenvironment in vivo. Our data indicate that RNA editing contributes to mesothelioma heterogeneity and highlights an important role of ADAR2 not only in growth regulation in mesothelioma but also in chemotherapy response, in addition to regulating inflammatory response downstream of sensing nucleic acid structures.

We previously observed increased levels of adenosine‐deaminase‐acting‐on‐dsRNA (Adar)‐dependent RNA editing during mesothelioma development in mice exposed to asbestos. The aim of this study was to characterize and assess the role of ADAR‐dependent RNA editing in mesothelioma. We found that tumors and mesothelioma primary cultures have higher ADAR‐mediated RNA editing compared to mesothelial cells. Unsupervised clustering of editing in different genomic regions revealed heterogeneity between tumor samples as well as mesothelioma primary cultures. ADAR2 expression levels are higher in BRCA1‐associated protein 1 wild‐type tumors, with corresponding changes in RNA editing in transcripts and 3'UTR. ADAR2 knockdown and rescue models indicated a role in cell proliferation, altered cell cycle, increased sensitivity to antifolate treatment, and type‐1 interferon signaling upregulation, leading to changes in the microenvironment in vivo. Our data indicate that RNA editing contributes to mesothelioma heterogeneity and highlights an important role of ADAR2 not only in growth regulation in mesothelioma but also in chemotherapy response, in addition to regulating inflammatory response downstream of sensing nucleic acid structures. [ABSTRACT FROM AUTHOR]

The concept that a breast cancer patient's menstrual stage at the time of tumor surgery influences risk of metastases remains controversial. The scarcity of comprehensive molecular studies of menstrual stage-dependent fluctuations in the breast provides little insight in this observation. To gain a deeper understanding of the biological changes in mammary tissue and blood during the menstrual cycle and to determine the influence of environmental exposures, such as low-dose ionizing radiation (LDIR), we used the mouse to characterize estrous-cycle variations in mammary gene transcripts by RNA-sequencing, peripheral white blood cell (WBC) counts and plasma cytokine levels. We identified an estrous-variable and hormone-dependent gene cluster enriched for Type-1 interferon genes. Cox regression identified a 117-gene signature of interferon-associated genes, which correlated with lower frequencies of metastasis in breast cancer patients. LDIR (10cGy) exposure had no detectable effect on mammary transcripts. However, peripheral WBC counts varied across the estrous cycle and LDIR exposure reduced lymphocyte counts and cytokine levels in tumor-susceptible mice. Our finding of variations in mammary Type-1 interferon and immune functions across the estrous cycle provides a mechanism by which timing of breast tumor surgery during the menstrual cycle may have clinical relevance to a patient's risk for distant metastases.

Background: Neuro-inflammation has long been implicated as a contributor to the progression of Alzheimer's disease in both humans and animal models. Type-1 interferons (IFNs) are pleiotropic cytokines critical in mediating the innate immune pro-inflammatory response. The production of type-1 IFNs following pathogen detection is, in part, through the activation of the toll-like receptors (TLRs) and subsequent signalling through myeloid differentiation factor-88 (Myd88) and interferon regulatory factors (IRFs). We have previously identified that neuronal type-1 IFN signalling, through the type-1 interferon alpha receptor-1 (IFNAR1), is detrimental in models of AD. Using an in vitro approach, this study investigated the TLR network as a potential production pathway for neuronal type-1 IFNs in response to Aβ. Methods: Wildtype and Myd88-/- primary cultured cortical and hippocampal neurons were treated with 2.5 μM Aβ1-42 for 24 to 72 h or 1 to 10 μM Aβ1-42 for 72 h. Human BE(2)M17 neuroblastoma cells stably expressing an IRF7 small hairpin RNA (shRNA) or negative control shRNA construct were subjected to 7.5 μM Aβ1-42/Aβ42-1 for 24 to 96 h, 2.5 to 15 μM Aβ1-42 for 96 h or 100 ng/ml LPS for 0.5 to 24 h. Q-PCR was used to analyse IFNα, IFNβ, IL-1β, IL-6 and TNFα mRNA transcript levels. Phosphorylation of STAT-3 was detected by Western blot analysis, and cell viability was assessed by MTS assay. Results: Reduced IFNα, IFNβ, IL-1β, IL-6 and TNFα expression was detected in Aβ1-42-treated Myd88-/- neurons compared to wildtype cells. This correlated with reduced phosphorylation of STAT-3, a downstream type-1 IFN signalling mediator. Significantly, Myd88-/- neuronal cultures were protected against Aβ1-42-induced neurotoxicity compared to wildtype as determined by MTS assay. Knockdown of IRF7 in M17 cells was sufficient in blocking IFNα, IFNβ and p-STAT-3 induction to both Aβ1-42 and the TLR4 agonist LPS. M17 IRF7 KD cells were also protected against Aβ1-42-induced cytotoxicity. Conclusions: This study confirms that the neuronal type-1 IFN response to soluble amyloid is mediated primarily through TLRs. This production is dependent upon Myd88 and IRF7 signalling. This study suggests that targeting this pathway to modulate neuronal type-1 IFN levels may be beneficial in controlling Aβ-induced neurotoxicity. [ABSTRACT FROM AUTHOR]

Background Hypoxic-ischaemic injuries such as stroke and traumatic brain injury exhibit features of a distinct neuro-inflammatory response in the hours and days post-injury. Microglial activation, elevated pro-inflammatory cytokines and macrophage infiltration contribute to core tissue damage and contribute to secondary injury within a region termed the penumbra. Type-1 interferons (IFNs) are a super-family of pleiotropic cytokines that regulate pro-inflammatory gene transcription via the classical Jak/Stat pathway; however their role in hypoxia-ischaemia and central nervous system neuro-inflammation remains unknown. Using an in vitro approach, this study investigated the role of type-1 IFN signalling in an inflammatory setting induced by oxygen glucose deprivation (OGD). Methods Human BE(2)M17 neuroblastoma cells or cells expressing a type-1 interferon-α receptor 1 (IFNAR1) shRNA or negative control shRNA knockdown construct were subjected to 4.5 h OGD and a time-course reperfusion period (0 to 24 h). Q-PCR was used to evaluate IFNα, IFNβ, IL-1β, IL-6 and TNF-α cytokine expression levels. Phosphorylation of signal transducers and activators of transcription (STAT)-1, STAT-3 and cleavage of caspase-3 was detected by western blot analysis. Post-OGD cellular viability was measured using a MTT assay. Results Elevated IFNα and IFNβ expression was detected during reperfusion post-OGD in parental M17 cells. This correlated with enhanced phosphorylation of STAT-1, a downstream type-1 IFN signalling mediator. Significantly, ablation of type-1 IFN signalling, through IFNAR1 knockdown, reduced IFNα, IFNβ, IL-6 and TNF-α expression in response to OGD. In addition, MTT assay confirmed the IFNAR1 knockdown cells were protected against OGD compared to negative control cells with reduced pro-apoptotic cleaved caspase-3 levels. Conclusions This study confirms a role for type-1 IFN signalling in the neuro-inflammatory response following OGD in vitro and suggests its modulation through therapeutic blockade of IFNAR1 may be beneficial in reducing hypoxia-induced neuro-inflammation. [ABSTRACT FROM AUTHOR]

Type-1 interferons (IFNs) are pleiotropic cytokines that signal through the type-1 IFN receptor (IFNAR1). Recent literature has implicated the type-1 IFNs in disorders of the CNS. In this study, we have investigated the role of type-1 IFNs in neuroinflammation following traumatic brain injury (TBI). Using a controlled cortical impact model, TBI was induced in 8- to 10-week-old male C57BL/6J WT and IFNAR1(-/-) mice and brains were excised to study infarct volume, inflammatory mediator release via quantitative PCR analysis and immune cell profile via immunohistochemistry. IFNAR1(-/-) mice displayed smaller infarcts compared with WT mice after TBI. IFNAR1(-/-) mice exhibited an altered anti-inflammatory environment compared with WT mice, with significantly reduced levels of the proinflammatory mediators TNFα, IL-1β and IL-6, an up-regulation of the anti-inflammatory mediator IL-10 and an increased activation of resident and peripheral immune cells after TBI. WT mice injected intravenously with an anti-IFNAR1 blocking monoclonal antibody (MAR1) 1 h before, 30 min after or 30 min and 2 d after TBI displayed significantly improved histological and behavioral outcome. Bone marrow chimeras demonstrated that the hematopoietic cells are a peripheral source of type-1 IFNs that drives neuroinflammation and a worsened TBI outcome. Type-1 IFN mRNA levels were confirmed to be significantly altered in human postmortem TBI brains. Together, these data demonstrate that type-1 IFN signaling is a critical pathway in the progression of neuroinflammation and presents a viable therapeutic target for the treatment of TBI.