Inflamed Mucosal Tissues Research Articles

Morphological Assessment of the Influence of Gold Nanosolution on Reparative Processes in Chronic Gingivitis

The article discusses the evaluation of the effectiveness of treating chronic gingivitis in experimental animals using a gold nanosolution. It presents the results of morphological studies aimed at studying changes in the tissues of cats suffering from chronic gingivitis after the introduction of gold nanoparticles under the mucous membrane. The aim of the study was to determine the effect of a gold nanosolution in the treatment of chronic gingivitis in 20 mongrel cats aged 2 to 4 years. Materials and methods: A group of cats diagnosed with chronic gingivitis was formed for the experiment. The experiment was carried out in accordance with the "European Convention for the Protection of Animals Used for Experimental and Scientific Purposes" dated March 18, 1986. All cats had a history of severe inflammatory processes in the oral cavity, which caused pain when eating solid food. After eating such food, the animals often had bloody saliva. Most of them suffered from weight loss, which posed a serious threat to their health. The oral cavity condition assessment included visual inspection and photo recording. The surgical process in each case included preparation of the surgical field with plaque removal and polishing of the teeth with a special paste. Before comprehensive teeth cleaning, the animals had their inflamed mucosal tissue cut off. Experimental studies conducted by the authors demonstrated the high therapeutic efficacy of gold nanosolution in the treatment of chronic gingivitis. There was a complete absence of signs of inflammation, such as bleeding, abnormal tooth mobility, or discharge during palpation of the gums, which confirmed the pronounced regenerative effect of gold nanoparticles.

Helicobacter pylori disrupts gastric mucosal homeostasis by stimulating macrophages to secrete CCL3

BackgroundHelicobacter pylori (H. pylori) is the predominant etiological agent of gastritis and disrupts the integrity of the gastric mucosal barrier through various pathogenic mechanisms. After H. pylori invades the gastric mucosa, it interacts with immune cells in the lamina propria. Macrophages are central players in the inflammatory response, and H. pylori stimulates them to secrete a variety of inflammatory factors, leading to the chronic damage of the gastric mucosa. Therefore, the study aims to explore the mechanism of gastric mucosal injury caused by inflammatory factors secreted by macrophages, which may provide a new mechanism for the development of H. pylori-related gastritis.MethodsThe expression and secretion of CCL3 from H. pylori infected macrophages were detected by RT-qPCR, Western blot and ELISA. The effect of H. pylori-infected macrophage culture medium and CCL3 on gastric epithelial cells tight junctions were analyzed by Western blot, immunofluorescence and transepithelial electrical resistance. EdU and apoptotic flow cytometry assays were used to detect cell proliferation and apoptosis levels. Dual-luciferase reporter assays and chromatin immunoprecipitation assays were used to study CCL3 transcription factors. Finally, gastric mucosal tissue inflammation and CCL3 expression were analyzed by hematoxylin and eosin staining and immunohistochemistry.ResultsAfter H. pylori infection, CCL3 expressed and secreted from macrophages were increased. H. pylori-infected macrophage culture medium and CCL3 disrupted gastric epithelial cells tight junctions, while CCL3 neutralizing antibody and receptor inhibitor of CCL3 improved the disruption of tight junctions between cells. In addition, H. pylori-infected macrophage culture medium and CCL3 recombinant proteins stimulated P38 phosphorylation, and P38 phosphorylation inhibitor improved the disruption of tight junctions between cells. Besides, it was identified that STAT1 was a transcription factor of CCL3 and H. pylori stimulated macrophage to secret CCL3 through the JAK1-STAT1 pathway. Finally, after mice were injected with murine CCL3 recombinant protein, the gastric mucosal injury and inflammation were aggravated, and the phosphorylation level of P38 was increased.ConclusionsIn summary, our findings demonstrate that H. pylori infection stimulates macrophages to secrete CCL3 via the JAK1-STAT1 pathway. Subsequently, CCL3 damages gastric epithelial tight junctions through the phosphorylation of P38. This may be a novel mechanism of gastric mucosal injury in H. pylori-associated gastritis.

INFLAMED INTESTINAL ENDOTHELIAL CELLS ESTABLISH SELF-REGULATORY NICHES VIA IL16 DEPENDENT RECRUITMENT OF CD4 EXPRESSING VESSEL-ASSOCIATED MACROPHAGES

Abstract Macrophages, play important roles in initiation and resolution of inflammation. Notably, a subset of tissue macrophages strategically localizes to the blood vessels, exerting essential regulatory functions at the blood-tissue interface, including regulation of vascular permeability and neutrophil (PMN) transendothelial migration (TEM). Although the number of vessel-associated macrophages (VAMs) is increased in inflamed tissue, the underlying mechanisms of VAMs recruitment are unknown. Our current study uncovers a novel mechanism whereby inflamed intestinal vascular endothelial cells (ECs) release IL-16 to selectively recruit CD4+ tissue macrophages to become VAMs. Whole-mount confocal microscopy studies in CX3CR1-EGFP macrophages reporter mice confirmed significant increases in VAMs numbers in several murine models of intestinal inflammation. Surprisingly, the majority of VAMs were found to express a classical T cell marker, CD4 and to be of an inflammatory phenotype, enriched for ICAM-1 and TNFα expression. VAMs-derived TNFα was previously found to prime ECs to form PMN TEM hot spots. Whole genome mRNA sequencing, and flow cytometry protein expression analyses revealed heightened expression of the CD4 ligand, IL-16 by inflamed intestinal lamina propria ECs. In vitro, using transwell assays, recombinant IL-16 and supernatants derived from murine (bEnds.3) endothelial cells induced robust migration of murine, LPS/IFNγ-stimulated bone marrow-derived macrophages. Whereas antibody-mediated IL-16 or CD4 neutralization in cultures and in vivo reduced VAMs recruitment. Collectively, our findings establish CD4 as a novel marker of VAMs and identify the regulatory role of ECs IL-16 and macrophages CD4+ axis in VAMs recruitment in inflamed mucosal tissues.

Toxigenic Clostridium perfringens Isolated from At-Risk Paediatric Inflammatory Bowel Disease Patients.

This study aimed to identify microbial drivers of inflammatory bowel disease [IBD], by investigating mucosal-associated bacteria and their detrimental products in IBD patients. We directly cultured bacterial communities from mucosal biopsies from paediatric gastrointestinal patients and examined for pathogenicity-associated traits. Upon identifying Clostridium perfringens as toxigenic bacteria present in mucosal biopsies, we isolated strains and further characterized toxicity and prevalence. Mucosal biopsy microbial composition differed from corresponding stool samples. C. perfringens was present in eight of nine patients' mucosal biopsies, correlating with haemolytic activity, but was not present in all corresponding stool samples. Large IBD datasets showed higher C. perfringens prevalence in stool samples of IBD adults [18.7-27.1%] versus healthy controls [5.1%]. In vitro, C. perfringens supernatants were toxic to cell types beneath the intestinal epithelial barrier, including endothelial cells, neuroblasts, and neutrophils, while the impact on epithelial cells was less pronounced, suggesting C. perfringens may be particularly damaging when barrier integrity is compromised. Further characterization using purified toxins and genetic insertion mutants confirmed perfringolysin O [PFO] toxin was sufficient for toxicity. Toxin RNA signatures were found in the original patient biopsies by PCR, suggesting intestinal production. C. perfringens supernatants also induced activation of neuroblast and dorsal root ganglion neurons in vitro, suggesting C. perfringens in inflamed mucosal tissue may directly contribute to abdominal pain, a frequent IBD symptom. Gastrointestinal carriage of certain toxigenic C. perfringens may have an important pathogenic impact on IBD patients. These findings support routine monitoring of C. perfringens and PFO toxins and potential treatment in patients.

Interrelationship between Candida Colonization, Dentures, and Mucosal Tissue Inflammation in the Pathogenesis of Denture Stomatitis.

Despite being common, the pathogenesis of denture stomatitis (DS) is poorly known; thus, this study was conducted to examine the relationship between candida, dentures, and mucosal tissue inflammation. One hundred and twenty edentulous patients wearing a denture with clinical signs and symptoms of DS and 30 patients without DS as healthy were involved in the study. Patients with DS were divided into three groups according to Newton's classification and fungal colonies, and denture fit was assessed. No significant difference was observed between age, sex, and denture fit between the two groups (P > 0.05). The fungal colonies in patients with DS were significantly more than the controls. The majority of the patients with good denture fit had degree 1 (localized mucosal inflammation), while the majority of the patients with fair denture fit had degree 2 (diffuse inflammation on the denture bearing area) and the majority with poor denture fit had degree 3 (granular type) (P < 0.001). The fungal colonies were negative for the majority of degree 1 patients (57.1%), while they were positive for the majority of patients with degree 2 (61.3%) and degree 3 (63.2%) inflammation (P = 0.003). We concluded that the pathogenesis of DS is elusive. Multiple factors, including lack of hygiene, reduced salivary flow, poor denture care, and fit, provide an easy pathway for Candida strains to colonize dentures.

Omega-3 nanoemulgel in prevention of radiation-induced oral mucositis and its associated effect on microbiome: a randomized clinical trial

BackgroundOral mucositis (OM) is recognized as one of the most frequent debilitating sequelae encountered by head and neck cancer (HNC) patients treated by radiotherapy. This results in severe mucosal tissue inflammation and oral ulcerations that interfere with patient’s nutrition, quality of life (QoL) and survival. Omega-3 (ω-3) polyunsaturated fatty acids (PUFAs) have recently gained special interest in dealing with oral diseases owing to its anti-inflammatory, anti-oxidant and wound healing properties. Thus, this study aims to assess topical Omega-3 nanoemulgel efficacy in prevention of radiation-induced oral mucositis and regulation of oral microbial dysbiosis.Materials and methodsThirty-four head and neck cancer patients planned to receive radiotherapy were randomly allocated into two groups: Group I: conventional preventive treatment and Group II: topical Omega-3 nanoemulgel. Patients were evaluated at baseline, three and six weeks after treatment using the World Health Organization (WHO) grading system for oral mucositis severity, Visual Analogue Scale (VAS) for perceived pain severity, and MD-Anderson Symptom Inventory for Head and Neck cancer (MDASI-HN) for QoL. Oral swabs were collected to assess oral microbiome changes.ResultsVAS scores and WHO mucositis grades were significantly lower after six weeks of treatment with topical Omega-3 nanoemulgel when compared to the conventional treatment. The total MDASI score was significantly higher in the control group after three weeks of treatment, and the head and neck subscale differed significantly at both three and six weeks. A significant reduction in Firmicutes/Bacteroidetes ratio was observed after six weeks in the test group indicating less microbial dysbiosis.ConclusionsTopical Omega-3 nanoemulgel demonstrated a beneficial effect in prevention of radiation-induced oral mucositis with a possibility of regulating oral microbial dysbiosis.

LAMB3 Promotes Intestinal Inflammation Through SERPINA3 and Is Directly Transcriptionally Regulated by P65 in Inflammatory Bowel Disease.

Various extracellular matrix (ECM) reshaping events are involved in inflammatory bowel disease (IBD). LAMB3 is a vital subunit of laminin-332, an important ECM component. Data on the biological function of LAMB3 in intestinal inflammation are lacking. Our aim is to discuss the effect of LAMB3 in IBD. LAMB3 expression was assessed in cultured intestinal epithelial cells, inflamed mucosal tissues of patients and mouse colitis models. RNA sequencing, quantitative real-time polymerase chain reaction and Western blotting were used to detect the LAMB3 expression distribution and potential downstream target genes. Dual-luciferase assays and chromatin immunoprecipitation-quantitative polymerase chain reaction were used to determine whether P65 could transcriptionally activate LAMB3 under tumor necrosis factor α stimulation. LAMB3 expression was increased in inflammatory states in intestinal epithelial cells and colonoids and was associated with adverse clinical outcomes in Crohn's disease. Knockdown of LAMB3 inhibited the expression of proinflammatory cytokines. Mechanistically, LAMB3 expression was directly transcriptionally activated by P65 and was inhibited by nuclear factor kappa B inhibitors under tumor necrosis factor α stimulation. Furthermore, RNA sequencing and replenishment experiments revealed that LAMB3 upregulated SERPINA3 to promote intestinal inflammation via the integrin α3β1/FAK pathway. We propose that LAMB3 could serve as a potential therapeutic target of IBD and a predictor of intestinal stenosis of Crohn's disease. Our findings demonstrate the important role of ECM in the progression of IBD and offer an experimental basis for the treatment and prognosis of IBD.

Inhibition of Soluble Stem Cell Factor Promotes Intestinal Mucosal Repair.

Incidences of inflammatory bowel disease (IBD), including Crohn's disease and ulcerative colitis, are escalating worldwide and can be considered a global public health problem. Given that the gold standard approach to IBD therapeutics focuses on reducing the severity of symptoms, there is an urgent unmet need to develop alternative therapies that halt not only inflammatory processes but also promote mucosal repair. Previous studies have identified increased stem cell factor (SCF) expression in inflamed intestinal mucosal tissues. However, the role that SCF plays in mediating intestinal inflammation and repair has not been explored. Changes in the expression of SCF were evaluated in the colonic tissue of healthy mice and during dextran sodium sulfate (DSS)-induced colitis. Furthermore, mucosal wound healing and colitis severity were analyzed in mice subjected to either mechanical biopsy or DSS treatment, respectively, following intestinal epithelial cell-specific deletion of SCF or anti-SCF antibody administration. We report robust expression of SCF by intestinal epithelial cells during intestinal homeostasis with a switch to immune cell-produced SCF during colitis. Data from mice with intestinal epithelial cell-specific deletion of SCF highlight the importance of immune cell-produced SCF in driving the pathogenesis of colitis. Importantly, antibody-mediated neutralization of total SCF or the specific SCF248 isoform decreased immune cell infiltration and enhanced mucosal wound repair following biopsy-induced colonic injury or DSS-induced colitis. These data demonstrate that SCF functions as a pro-inflammatory mediator in mucosal tissues and that specific neutralization of SCF248 could be a viable therapeutic option to reduce intestinal inflammation and promote mucosal wound repair in individuals with IBD.

The role of immune modulatory CD163+ macrophages and FOXP3+ T regulatory lymphocytes in ulcerative colitis

Abstract Background Recently, research work was intensified to explore the role of the immune microenvironment in different diseases. The inflammatory Bowel Disease- Distribution, Chronicity, Activity score (IBD-DCA) is now accepted as a practical reproducible tool for assessment of the histologic inflammatory burden and histologic mucosal healing in ulcerative colitis (UC) endoscopic biopsies. The particular contribution of immune modulatory CD 163+ macrophages and FOXP3+T regulatory lymphocytes (T-regs), and their implication in UC pathogenesis and course are still not clearly elaborated. Correlation between these attributes and the histologic indices would offer valuable insights that could help tailor the management plan on a personalized medicine protocols level, in addition to paving roads to new therapeutic target modalities. Aim of the study Evaluate the role of immune modulatory CD163+ macrophages and FOXP3+ T regulatory lymphocytes in ulcerative colitis and correlate their immunohistochemical expression with the pathological parameters of Inflammatory Bowel Disease- Distribution, Chronicity, Activity score (IBD-DCA score). Materials and methods Paraffin-embedded tissue sections from 60 cases of endoscopic colonic biopsies diagnosed as ulcerative colitis were immunohistochemically studied for CD163 and FOXP3 expression and graded semi-quantitively. Furthermore, histopathological features were evaluated according to IBD-DCA score and correlated with CD163 and FOXP3 expression for statistical analysis. Results CD163+ macrophages and FOXP3+ T-regs were demonstrated in 100% (60/60) and 78% (47/60) respectively of the lamina propria of ulcerative colitis cases. Significant correlation with activity (A) parameter of DCA-score and architectural distortion of detailed chronicity parameter for both markers was detected. Additionally, CD163 immuno-expression showed significant correlation with detailed activity parameters while FOXP3 presented a significant correlation with the chronicity parameter of DCA score. Conclusion The immune modulatory CD 163+ macrophages and FOXP3+T-regs represent key players in mucosal tissue inflammation, disease activity and chronicity in UC. This could offer new therapeutic modalities targeting the players of the immune microenvironment that should be deeply investigated in future studies.

Integration of an intraoral scan and a conventional impression for fabricating complete dentures for a patient with flabby tissues

Inflammatory movable tissues in the maxillary anterior region are the result of excessive stimulation of the anterior alveolar ridge, as the maxillary denture habitually rotates anteriorly and upward during mastication. The pressure required for a functional impression makes it difficult to obtain the accurate anatomy of the inflamed mucosal tissues. An intraoral scanner can be used to record the movable tissues in an immobile state. However, for removable dentures, the oral scanner is limited by the difficulty in evaluating the denture borders or the posterior palatal seal area accurately. The fabrication of a complete denture by combining the use of an oral scanner to capture an anatomic impression without exerting pressure on the maxilla, including the movable tissues, and a traditional functional impression using the closed-mouth technique is described.

Concept of Kshara Karma in Sushruta Samhita and Management of Nasarsha (Nasal Polyp) with Pratisaraneeya Kshara

Sushruta has mentioned 31 Rogas of Nasa in which Nasarsha is described. Nasarsha can be correlated to Nasal polyp. It is a benign mass of inflamed mucosal tissue of Nasal wall. Some common symptoms of Nasal polyp is Nasal congestion, sneezing, headache and runny nose. The prevalence rate of Nasal polyps is approximately 1% to 4% in general population. Certain medications and surgeries are used to treat Nasal Polyp in modern science with major reccurence rate. In Ayurveda, Acharya Sushruta has described various treatment of Arsha in Sushruta Chikitsha Sthan e.g. Bheshaja, Kshara, Agni and Shastra which is also common treatment of Nasarsha in general. Among them Kshara is best Anusastra in the treatment of Arsha, so this study is being carried out. Aim and Objective: Role of Pratisaraneeya Kshara in the management of Nasarsha (Nasal Polyp) and review of Kshara Karma through conceptual study. Material and methods: Treatment for Arsha and various Kshara Karma as mentioned by Acharya Sushruta in Sushruta Samhita with various commentaries will be studied thoroughly. Conclusion: Kshara Karma can be used as Ayurvedic line of treatment for Nasal Polyp as it is safe and effective method and might be better choice of intervention to reduce recurrence rate.

Can polyphenolic surface modifications prevent fungal colonization of titanium dental implants?

Oral biofilms can be a major health problem causing infections and chronic inflammation of mucosal tissue. While much effort is put in the investigation of bacteria in biofilms, the role of fungi is often neglected, despite Candida albicans playing a key role in the formation of multispecies oral biofilms. With the rise of antibiotic resistance, new strategies to reduce microbial growth need to be found. Therefore, plant derived polyphenolic molecules have been suggested to reduce both adhesion and growth of pathogenic bacteria and fungi. In this study, we investigated the use of polyphenolic coatings to reduce adhesion and biofilm formation of C. albicans BWP17 on titanium implants. Tannic acid and pyrogallol coatings altered the hydrophobic and charge properties of titanium surfaces, and both compounds were gradually released as active molecules over time. Despite such effects, we found no significant inhibition on growth and biofilm formation of C. Albicans, indicating that the release of active molecules from the coatings did not reach relevant inhibitory concentrations. However, a potential antibiofilm effect was observed by the pH-dependent disassembly of the polyphenolic layer, which caused the biofilm to detach. Hence, further efforts are required to create tailored implant surfaces, which sustainably reduce microbial growth and adhesion.

NOD2 PROMOTES HOST DEFENSE AND RECOVERY INDUCING MACROPHAGE-MEDIATED INNATE LYMPHOID CELLS TYPE 3 ACTIVATION FOLLOWING FUNGAL INFECTION IN EXPERIMENTAL COLITIS

Abstract Recent studies have documented the complexity of the intestinal fungal community (‘mycobiome’) in mice, and clinical and experimental observations have shown that the mycobiome influences both gut health and disease, e.g., inflammatory bowel disease (IBD). In fact, prior studies have shown that Crohn’s disease (CD) patients, compared to healthy controls, harbor higher levels of intestinal Candida tropicalis (Ct), which is the major fungal species detected in the colons of colitic mice after DSS challenge. More recently, Debaryomyces hansenii (also known as Candida famata) has been found in intestinal wounds of mice and inflamed mucosal tissues of CD patients. Moreover, proteins encoded by genes within IBD susceptibility loci, such as the pattern recognition receptor (PRR), NOD2, are known not only to recognize bacterial components, but also a fungal cell wall element, chitin. In fact, the role of PRRs in regulating immunity against intestinal fungi, and how fungi influence IBD remains poorly defined. We challenged DSS colitic WT and Nod2-/- mice with Ct 2 days before DSS administration and subsequently on day (d)0, 3 and 6. Our data confirms previous studies that Ct challenge does not exacerbate colitis in DSS-treated C57BL/6 wildtype (WT) mice, however, Ct-infected Nod2-/- mice possess a higher fungal burden and exhibit worse colitis symptoms, such as weight loss, decreased stool consistency, and presence of blood in stools, vs. Ct-infected WT mice, indicating an essential and protective role for NOD2 during colitis recovery after Ct challenge. Our results also show that Ct-infected Nod2-/- mice display a marked reduction in colonic Il22 and Il17, which are cytokines previously reported to be important in maintaining epithelial barrier integrity during DSS colitis, These data were confirmed in colons of Ct infected DSS challenged, ileitis-prone SAMP1/YitFc (SAMP) mice that were deficient in NOD2. Moreover, Our in vitro data show, a decrease in Il1b and Il23 in bone marrow-derived macrophages from SAMP Nod2-/- mice compared to WT after 2h of exposure to chitin. IL-17+ innate lymphoid cells (ILCs) are also known to control fungal burden during opportunistic fungal infections, and interestingly, our findings indicate that Ct infection of Nod2-/- vs. WT mice results in a decreased frequency of mesenteric lymph node–derived type 3 ILCs (ILC3s), suggesting that delay in fungal clearance and recovery in Nod2-/- mice may be due to the inability to mount protective type 3 immune responses. Taken together, the data so far collected suggests that NOD2 is essential to maintain gut mycobiome homeostasis and drives protective innate immune responses, via a macrophage-mediated ILC3 recruitment and IL-17 mechanism, by preventing the overgrowth of opportunistic fungi that may contribute to chronic intestinal inflammation, such as that observed in CD.

Helicobacter pylori BabA-SabA Key Roles in the Adherence Phase: The Synergic Mechanism for Successful Colonization and Disease Development.

Helicobacter pylori is a pathogenic microorganism that successfully inhabits the human stomach, colonizing it by producing several virulence factors responsible for preventing host self-defense mechanisms. The adherence mechanism to gastric mucosal tissue is one of the most important processes for effective colonization in the stomach. The blood group antigen-binding adhesion (BabA) and sialic acid-binding adherence (SabA) are two H. pylori outer membrane proteins able to interact with antigens in the gastroduodenal tract. H. pylori possesses several mechanisms to control the regulation of both BabA and SabA in either the transcriptional or translational level. BabA is believed to be the most important protein in the early infection phase due to its ability to interact with various Lewis antigens, whereas SabA interaction with sialylated Lewis antigens may prove important for the adherence process in the inflamed gastric mucosal tissue in the ongoing-infection phase. The adherence mechanisms of BabA and SabA allow H. pylori to anchor in the gastric mucosa and begin the colonization process.

Debaryomyces is enriched in Crohn's disease intestinal tissue and impairs healing in mice.

Alterations of the mycobiota composition associated with Crohn's disease (CD) are challenging to link to defining elements of pathophysiology, such as poor injury repair. Using culture-dependent and -independent methods, we discovered that Debaryomyces hansenii preferentially localized to and was abundant within incompletely healed intestinal wounds of mice and inflamed mucosal tissues of CD human subjects. D. hansenii cultures from injured mice and inflamed CD tissues impaired colonic healing when introduced into injured conventionally raised or gnotobiotic mice. We reisolated D. hansenii from injured areas of these mice, fulfilling Koch's postulates. Mechanistically, D. hansenii impaired mucosal healing through the myeloid cell-specific type 1 interferon-CCL5 axis. Taken together, we have identified a fungus that inhabits inflamed CD tissue and can lead to dysregulated mucosal healing.

Psoriasis Tanılı Hastada Methotreksat Toksisitesine Bağlı Gelişen Inflamatuar Kolit: Olgu Sunumu

Methotrexate is known as a folate antimetabolite. The side effects of methotrexate are not usually seen in low dosages. Here we present a patient with inflammatory colitis due to methotrexate use for psoriasis.A 29 year-old male who was diagnosed with psoriasis 1 year ago and started to use methotrexate for 2 weeks; applied to emergency with acute abdomen symptoms. According to the tests and examinations the patient was diagnosed with inflammatory colitis due to methotrexate toxicity. The patient was observed for abdominal pain without surgical interventions and had folic acid therapy combined with empiric antibiotherapy. Methotrexate side effects are usually seen as bone marrow suppression and mucosal tissue inflammation therefore some side effects can be missed in clinical examinations. As a result, we should consider that in patients applying to emergency with acute abdomen symptoms drugs can be the cause of this clinical presentation.

Steroid-resistant human inflammatory ILC2s are marked by CD45RO and elevated in type 2 respiratory diseases.

Group 2 innate lymphoid cells (ILC2s) orchestrate protective type 2 immunity and have been implicated in various immune disorders. In the mouse, circulatory inflammatory ILC2s (iILC2s) were identified as a major source of type 2 cytokines. The human equivalent of the iILC2 subset remains unknown. Here, we identify a human inflammatory ILC2 population that resides in inflamed mucosal tissue and is specifically marked by surface CD45RO expression. CD45RO+ ILC2s are derived from resting CD45RA+ ILC2s upon activation by epithelial alarmins such as IL-33 and TSLP, which is tightly linked to STAT5 activation and up-regulation of the IRF4/BATF transcription factors. Transcriptome analysis reveals marked similarities between human CD45RO+ ILC2s and mouse iILC2s. Frequencies of CD45RO+ inflammatory ILC2 are increased in inflamed mucosal tissue and in the circulation of patients with chronic rhinosinusitis or asthma, correlating with disease severity and resistance to corticosteroid therapy. CD45RA-to-CD45RO ILC2 conversion is suppressed by corticosteroids via induction of differentiation toward an immunomodulatory ILC2 phenotype characterized by low type 2 cytokine and high amphiregulin expression. Once converted, however, CD45RO+ ILC2s are resistant to corticosteroids, which is associated with metabolic reprogramming resulting in the activation of detoxification pathways. Our combined data identify CD45RO+ inflammatory ILC2s as a human analog of mouse iILC2s linked to severe type 2 inflammatory disease and therapy resistance.

NADPH oxidase 4 is protective and not fibrogenic in intestinal inflammation

Dysregulated redox signaling and oxidative injury are associated with inflammatory processes and fibrosis. H2O2 generation by NOX4 has been suggested as a key driver in the development of fibrosis and a small molecule drug is under evaluation in clinical trials for idiopathic pulmonary fibrosis and primary biliary cholangitis. Fibrosis is a common complication in Crohn's disease (CD) leading to stricture formation in 35–40% of patients, who require surgical interventions in the absence of therapeutic options. Here we assess NOX4 expression in CD patients with inflammatory or stricturing disease and examine whether loss of NOX4 is beneficial in acute and fibrotic intestinal disease. NOX4 was upregulated in inflamed mucosal tissue of CD and ulcerative colitis (UC) patients, in CD ileal strictures, and in mice with intestinal inflammation. Nox4 deficiency in mice promoted pathogen colonization and exacerbated tissue injury in acute bacterial and chemical colitis. In contrast, in two chronic injury models aberrant tissue remodeling and fibrosis-related gene expression did not differ substantially between Nox4−/− mice and wildtype mice, suggesting that Nox4 is dispensable in TGF-β1-driven intestinal fibrogenesis. While animal models do not recapitulate all the hallmarks of CD fibrosis, the tissue-protective role of Nox4 warrants a cautious approach to pharmacological inhibitors.

Lymphocyte Activation Gene (LAG)-3 Is Associated With Mucosal Inflammation and Disease Activity in Ulcerative Colitis.

Background and AimsLymphocyte activation gene [LAG]-3 is an immune checkpoint and its expression identifies recently activated lymphocytes that may contribute to inflammation. We investigated the role of LAG-3 by analysing its expression and function in immune cells from blood and tissue of patients with ulcerative colitis [UC].MethodsThe phenotypic properties of LAG-3+ T cells were determined by flow cytometry, qRT-PCR and single-cell RNA-sequencing. LAG-3+ cells were quantified and correlated with disease activity. The functional effects of LAG-3+ cells were tested using a depleting anti-LAG-3 monoclonal antibody [mAb] in a mixed lymphocyte reaction [MLR].ResultsLAG-3+ cells in the blood were negligible. LAG-3+ lymphocytes were markedly increased in inflamed mucosal tissue and both frequencies of LAG-3+ T cells and transcript levels of LAG3 correlated with endoscopic severity. LAG-3 expression was predominantly on effector memory T cells, and single-cell RNA-sequencing revealed LAG3 expression in activated and cytokine-producing T cell subsets. Foxp3+CD25hi Tregs also expressed LAG-3, although most mucosal Tregs were LAG-3−. Mucosal LAG-3+ cells produced mainly interferon γ [IFNγ] and interleukin-17A. LAG-3+ cell numbers decreased in patients who responded to biologics, and remained elevated in non-responders. Treatment with a depleting anti-LAG-3 mAb led to a reduction in proliferation and IFNγ production in an MLR.ConclusionsLAG-3+ cells are increased in the inflamed mucosa, predominantly on effector memory T cells with an activated phenotype and their cell numbers positively correlate with disease activity. Depleting LAG-3 eliminates activated proliferating T cells, and hence LAG-3 could be a therapeutic target in UC.

Near infrared readouts offer sensitive and rapid assessments of intestinal permeability and disease severity in inflammatory bowel disease models

Intestinal permeability and neutrophil activity are closely linked to inflammatory bowel disease (IBD) pathophysiology. Here we discuss two techniques for assessing permeability and neutrophil activity in mouse IBD models using near infrared (NIR) detection. To address the limitation of visible light readouts—namely high background—IRDye 800CW was used to enable rapid, non-terminal measurements of intestinal permeability. The increased sensitivity of NIR readouts for colon permeability is shown using dextran sulfate sodium (DSS) and anti-CD40 murine colitis models in response to interleukin-22 immunoglobulin Fc (IL22Fc) fusion protein and anti-p40 monoclonal antibody treatments, respectively. In addition to enhanced permeability, elevated levels of neutrophil elastase (NE) have been reported in inflamed colonic mucosal tissue. Activatable NIR fluorescent probes have been extensively used for disease activity evaluation in oncologic animal models, and we demonstrate their translatability using a NE-activatable reagent to evaluate inflammation in DSS mice. Confocal laser endomicroscopy (CLE) and tissue imaging allow visualization of spatial NE activity throughout diseased colon as well as changes in disease severity from IL22Fc treatment. Our findings with the 800CW dye and the NE probe highlight the ease of their implementation in preclinical IBD research.