Resident Macrophages in SS

Macrophages (MΦs) are critical regulators of immune response and serve as a link between innate and acquired immunity. The precise mechanism of involvement of tissue-resident MΦs in the pathogenesis of autoimmune diseases is not clear. Here, using a murine model for Sjögren’s syndrome (SS), we investigated the role of tissue-resident MΦs in the onset and development of autoimmunity. Two unique populations of CD11bhigh and CD11blow resident MΦs were observed in the target tissue of the SS model. Comprehensive gene expression analysis of chemokines revealed effective production of CCL22 by the CD11bhigh MΦs. CCL22 upregulated the migratory activity of CD4+ T cells by increasing CCR4, a receptor of CCL22, on T cells in the SS model. In addition, CCL22 enhanced IFN-γ production of T cells of the SS model, thereby suggesting that CCL22 may impair the local immune tolerance in the target organ of the SS model. Moreover, administration of anti-CCL22 antibody suppressed autoimmune lesions in the SS model. Finally, histopathological analysis revealed numerous CCL22-producing MΦs in the minor salivary gland tissue specimens of the SS patients. CCL22-producing tissue-resident MΦs may control autoimmune lesions by enhancing T cell response in the SS model. These results suggest that specific chemokines and their receptors may serve as novel therapeutic or diagnostic targets for SS

Catecholamines Facilitate Fuel Expenditure and Protect Against Obesity via a Novel Network of the Gut-Brain Axis in Transcription Factor Skn-1-deficient Mice

AbstractTaste signals and nutrient stimuli sensed by the gastrointestinal tract are transmitted to the brain to regulate feeding behavior and energy homeostasis. This system is referred to as the gut-brain axis. Here we show that both brush cells and type II taste cells are eliminated in the gastrointestinal tract of transcription factor Skn-1 knockout (KO) mice. Despite unaltered food intake, Skn-1 KO mice have reduced body weight with lower body fat due to increased energy expenditure. In this model, 24-h urinary excretion of catecholamines was significantly elevated, accompanied by increased fatty acid β-oxidation and fuel dissipation in skeletal muscle and impaired insulin secretion driven by glucose. These results suggest the existence of brain-mediated energy homeostatic pathways originating from brush cells and type II taste cells in the gastrointestinal tract and ending in peripheral tissues, including the adrenal glands. The discovery of food-derived factors that regulate these cells may open new avenues the treatment of obesity and diabetes.Research ContextTaste signals and nutrient stimuli sensed by the gastrointestinal tract are transmitted to the brain to regulate feeding behavior and energy homeostasis along the gut-brain axis. We propose the concept that taste-receiving cells in the oral cavity and/or food-borne chemicals-receiving brush cells in the gut are involved in regulation of the body weight and adiposity via the brain. The discovery of food-derived factors that regulate these cells may open new avenues for the treatment of obesity and diabetes

Distinct Regulation of CXCL10 Production in Salivary Gland Cells

CXCL10, a CXC chemokine induced by interferon-gamma [IFN-γ], has been observed in a wide variety of chronic inflammatory disorders and autoimmune conditions. Although CXCL10 is known to be overexpressed in the salivary glands of individuals with primary Sjögren's syndrome (pSS), it is unclear which cells produce CXCL10 under what types of stimulations. Here we investigated the precise molecular mechanisms by which CXCL10 was produced in human salivary gland ductal (NS-SV-DC) and acinar (NS-SV-AC) cell lines. Our results demonstrated that NS-SV-DC cells produced higher levels of CXCL10 compared to NS-SV-AC cells. In addition, our findings demonstrated that the regulator of the enhancement of CXCL10 was different between NS-SV-DC and NS-SV-AC cells; i.e., interferon-gamma (IFN-γ) had more potential than interferon-alpha (IFN-α), tumor necrosis factor (TNF)-α, and interleukin (IL)1-β in the induction of CXCL10 production in NS-SV-DC cells, whereas TNF-α had potential to induce CXCL10 production in NS-SV-AC cells. A Western blot analysis demonstrated that IFN-γ enhanced the production of CXCL10 via both the JAK/STAT1 pathway and the NF-κB pathway in NS-SV-DC cells, whereas TNF-α enhanced the production of CXCL10 via the NF-κB pathway in NS-SV-AC cells. The results of study suggest that the CXCL10 overexpression in the salivary glands is caused mainly by IFN-γ-stimulated salivary gland ductal cells. The enhanced production of CXCL10 by IFN-γ from ductal cells may result in the inflammation of pSS lesions

CXCR3+ macrophage in Sjögren's syndrome

Background: Mechanisms underlying immune cells' recruitment and activation into the inflammatory lesions of lip salivary glands (LSGs) from primary Sjögren's syndrome (pSS) patients are incompletely understood. Chemokines play pivotal roles in these processes, so we investigated the clinical significance of chemokine receptor CXCR3 and its ligands in the autoimmune lesions of pSS. Methods: We histologically determined the grade of LSG samples from 22 pSS patients and subjected the samples to immunofluorescence analysis to determine the expressions of CXCR3 and its ligands: CXCL9, CXCL10, and CXCL11. To identify the immune cells expressing CXCR3 in the LSGs, we performed double immunofluorescence analysis using antibodies against CD3 (pan-T cells), CD80 (M1 macrophages), CD163 (M2 macrophage), and CD123 (plasmacytoid dendritic cells: pDCs). The relationship between the grade of lymphocytic infiltration and the number of positively stained cells was analyzed by Spearman's rank correlation test. Results: The expressions of CXCL9 and CXCL10 showed particularly intense staining in the LSG samples' ductal cells. The CXCR3 expression was detected mainly in CD80+ and CD163+ macrophages. The number of CXCR3+CD163+ macrophages inversely correlated with the LSG inflammatory lesions' severity (rs= −0.777, p<0.001). Conclusions: Our results suggest that the enhanced production of CXCL9 and CXCL10 from ductal cells results in the CXCR3+ macrophages' migration. There was an inverse correlation between these two parameters: i.e., the number of CXCR3+CD163+ macrophages decreased as the lymphocytic infiltration grade increased. Although CXCR3 is expressed in all of the innate immune cells, CXCR3+CD163+ M2 macrophages may contribute to the anti-inflammatory functions in pSS lesions

Involvement of the OTUB1-YAP1 axis in driving malignant behaviors of head and neck squamous cell carcinoma

Background: Comprehending the molecular mechanisms underlying head and neck squamous cell carcinoma (HNSCC) is vital for the development of effective treatment strategies. Deubiquitinating enzymes (DUBs), which regulate ubiquitin-dependent pathways, are potential targets for cancer therapy because of their structural advantages. Here we aimed to identify a potential target for HNSCC treatment among DUBs. Methods: A screening process was conducted using RNA sequencing data and clinical information from HNSCC patients in the TCGA database. A panel of 88 DUBs was analyzed to identify those associated with poor prognosis. Subsequently, HNSCC cells were modified to overexpress specific DUBs, and their effects on cell proliferation and invasion were evaluated. In vivo experiments were performed to validate the findings. Results: In HNSCC patients, USP10, USP14, OTUB1, and STAMBP among the screened DUBs were associated with a poor prognosis. Among them, OTUB1 showed the most aggressive characteristics in both in vitro and in vivo experiments. Additionally, OTUB1 regulated the stability and nuclear localization of YAP1, a substrate involved in cell proliferation and invasion. Notably, OTUB1 expression exhibited a positive correlation with the HNSCC-YAP score in HNSCC cells. Conclusions: This study highlights the critical role of OTUB1 in HNSCC progression via modulating YAP1. Targeting the OTUB1-YAP1 axis holds promise as a potential therapeutic strategy for HNSCC treatment

CCL22-Producing Resident Macrophages Enhance T Cell Response in Sjögren's Syndrome

Macrophages (MΦs) are critical regulators of immune response and serve as a link between innate and acquired immunity. The precise mechanism of involvement of tissue-resident MΦs in the pathogenesis of autoimmune diseases is not clear. Here, using a murine model for Sjögren's syndrome (SS), we investigated the role of tissue-resident MΦs in the onset and development of autoimmunity. Two unique populations of CD11bhigh and CD11blow resident MΦs were observed in the target tissue of the SS model. Comprehensive gene expression analysis of chemokines revealed effective production of CCL22 by the CD11bhigh MΦs. CCL22 upregulated the migratory activity of CD4+ T cells by increasing CCR4, a receptor of CCL22, on T cells in the SS model. In addition, CCL22 enhanced IFN-γ production of T cells of the SS model, thereby suggesting that CCL22 may impair the local immune tolerance in the target organ of the SS model. Moreover, administration of anti-CCL22 antibody suppressed autoimmune lesions in the SS model. Finally, histopathological analysis revealed numerous CCL22-producing MΦs in the minor salivary gland tissue specimens of the SS patients. CCL22-producing tissue-resident MΦs may control autoimmune lesions by enhancing T cell response in the SS model. These results suggest that specific chemokines and their receptors may serve as novel therapeutic or diagnostic targets for SS

Sour Taste Responses in Mice Lacking PKD Channels

The polycystic kidney disease-like ion channel PKD2L1 and its associated partner PKD1L3 are potential candidates for sour taste receptors. PKD2L1 is expressed in type III taste cells that respond to sour stimuli and genetic elimination of cells expressing PKD2L1 substantially reduces chorda tympani nerve responses to sour taste stimuli. However, the contribution of PKD2L1 and PKD1L3 to sour taste responses remains unclear.We made mice lacking PKD2L1 and/or PKD1L3 gene and investigated whole nerve responses to taste stimuli in the chorda tympani or the glossopharyngeal nerve and taste responses in type III taste cells. In mice lacking PKD2L1 gene, chorda tympani nerve responses to sour, but not sweet, salty, bitter, and umami tastants were reduced by 25–45% compared with those in wild type mice. In contrast, chorda tympani nerve responses in PKD1L3 knock-out mice and glossopharyngeal nerve responses in single- and double-knock-out mice were similar to those in wild type mice. Sour taste responses of type III fungiform taste cells (GAD67-expressing taste cells) were also reduced by 25–45% by elimination of PKD2L1.These findings suggest that PKD2L1 partly contributes to sour taste responses in mice and that receptors other than PKDs would be involved in sour detection

Multidetector-Row CT in Patients with Suspected Obstructive Jaundice: Comparison with Non-Contrast MRI with MR Cholangiopancreatography

We compared the diagnostic accuracy of multidetector-row computed tomography (MDCT) with multiplanar reconstruction (MPR) images to non-contrast magnetic resonance imaging (MRI) with magnetic resonance cholangiopancreatography (MRCP) (MRI/MRCP) for evaluating obstructive jaundice. MDCT and MRI/MRCP images from 53 patients with suspected obstructive jaundice were interpreted by two radiologists. These readers evaluated the images to determine level of obstruction, to differentiate between benign and malignant lesions, and to state the first-choice diagnosis with degree of confidence. We analyzed the obstruction levels in 50 patients excluding 3 patients who did not undergo direct cholangiography (DC). Both MDCT and MRI/MRCP showed almost perfect agreement with DC in two readers (statistic weighted kappa?0.80) in the determination of obstruction level. The mean area under the receiver operating characteristic curve for differentiating benign from malignant lesions was significantly (p=0.02) larger in MDCT (0.98) than in MRI/MRCP (0.86). We analyzed the first-choice diagnoses for 39 patients excluding 14 patients without final diagnosis confirmed. Readers had, out of 78 interpretations, a high confidence level in their first-choice diagnoses for 44 (56%) and 23 (29%) interpretations using MDCT and MRI/MRCP, respectively. In the interpretations made with high confidence level, 98% (43/44) and 91% (21/23) were correct for MDCT and MRI/MRCP, respectively. In conclusion, MDCT with MPR images is as accurate as MRI/MRCP for evaluating the biliary duct obstruction level, and has high diagnostic accuracy in evaluating the cause of jaundice. MDCT can provide sufficient information on the level of biliary obstruction and cause of obstructive jaundice