Bronchial epithelial cell transcriptome shows endotype heterogeneity of asthma in patients with NSAID-exacerbated respiratory disease.

BACKGROUND: Nonsteroidal anti-inflammatory drugs-exacerbated respiratory disease (N-ERD) is currently classified as a type-2 (T2) immune-mediated disease characterized by asthma, chronic rhinosinusitis, and hypersensitivity to cyclooxygenase-1 inhibitors. OBJECTIVES: The aim of this study was to characterize immunological endotypes of N-ERD based on the gene expression profile in the bronchial epithelium. METHODS: mRNA transcriptome (mRNA-sequencing) was analyzed in bronchial brushings from patients with N-ERD (n = 22), those with nonsteroidal anti-inflammatory drug-tolerant asthma (NTA, n = 21), and control subjects (n = 11). Additionally, lipid and protein mediators were measured in bronchoalveolar lavage fluid (BALF). RESULTS: Initial analysis of the entire asthma group revealed 2 distinct gene expression signatures: "T2-high" with increased expression of T2-related genes (eg, CLCA1, CST1), and "proinflammatory" characterized by the expression of innate immunity (eg, FOSB, EGR3) and IL-17A response genes. These endotypes showed similar prevalence in N-ERD and NTA (eg, T2-high: 33% and 32%, respectively). T2-high asthma was characterized by increased expression of mast cell and eosinophil markers, goblet cell hyperplasia, and elevated LTE4 and PGD2 in BALF. Patients with a proinflammatory endotype showed mainly neutrophilic inflammation and increased innate immunity mediators in BALF. Furthermore, the proinflammatory signature was associated with a more severe course of asthma and marked airway obstruction. These signatures could be recreated in vitro by exposure of bronchial epithelial cells to IL-13 (T2-high) and IL-17A (proinflammatory). CONCLUSIONS: T2-high signature was found only in one-third of patients with N-ERD, which was similar to what was found in patients with NTA. The proinflammatory endotype, which also occurred in N-ERD, suggests a novel mechanism of severe disease developing on a non-T2 background.

Co-Expression Analysis of Airway Epithelial Transcriptome in Asthma Patients with Eosinophilic vs. Non-Eosinophilic Airway Infiltration.

Asthma heterogeneity complicates the search for targeted treatment against airway inflammation and remodeling. We sought to investigate relations between eosinophilic inflammation, a phenotypic feature frequent in severe asthma, bronchial epithelial transcriptome, and functional and structural measures of airway remodeling. We compared epithelial gene expression, spirometry, airway cross-sectional geometry (computed tomography), reticular basement membrane thickness (histology), and blood and bronchoalveolar lavage (BAL) cytokines of n = 40 moderate to severe eosinophilic (EA) and non-eosinophilic asthma (NEA) patients distinguished by BAL eosinophilia. EA patients showed a similar extent of airway remodeling as NEA but had an increased expression of genes involved in the immune response and inflammation (e.g., KIR3DS1), reactive oxygen species generation (GYS2, ATPIF1), cell activation and proliferation (ANK3), cargo transporting (RAB4B, CPLX2), and tissue remodeling (FBLN1, SOX14, GSN), and a lower expression of genes involved in epithelial integrity (e.g., GJB1) and histone acetylation (SIN3A). Genes co-expressed in EA were involved in antiviral responses (e.g., ATP1B1), cell migration (EPS8L1, STOML3), cell adhesion (RAPH1), epithelial-mesenchymal transition (ASB3), and airway hyperreactivity and remodeling (FBN3, RECK), and several were linked to asthma in genome- (e.g., MRPL14, ASB3) or epigenome-wide association studies (CLC, GPI, SSCRB4, STRN4). Signaling pathways inferred from the co-expression pattern were associated with airway remodeling (e.g., TGF-ß/Smad2/3, E2F/Rb, and Wnt/ß-catenin).

Effect of omalizumab on bronchoalveolar lavage matrix metalloproteinases in severe allergic asthma.

INTRODUCTION: Airway inflammation in asthma is accompanied by reconstruction of the bronchial wall extracellular matrix that most likely occurs with a contribution of matrix metalloproteinases (MMPs). Recently we have reported that omalizumab may decrease reticular basement membrane (RBM) thickness together with fibronectin deposits in asthmatic airways, although mechanisms involved are unknown. OBJECTIVE: In the present study, we have investigated the impact of omalizumab on MMPs concentrations in bronchoalveolar lavage fluid (BAL) of asthmatic subjects in relation to airway remodeling changes in histology. PATIENTS AND METHODS: The study group consisted of 13 severe allergic asthmatics treated with omalizumab for at least 12 months. In each subject, clinical and laboratory parameters, bronchoscopy with BAL, and endobronchial biopsy were evaluated before and after the biologic therapy. RBM thickness, fibronectin, and collagen deposits in bronchial mucosa specimens were analyzed in histology. The investigations also included BAL cytology and BAL concentrations of MMP-2, -3, and -9. RESULTS: Omalizumab was related to a decrease in all measured MMPs in BAL (p < 0.001, each), although such declines were not observed in each patient. The depletions were associated with a lower asthma exacerbation rate and better asthma control. Interestingly, patients who showed a decline in at least one MMP (n = 10, 77%) were characterized by a higher decrease in the RBM thickness (-1.61 [-2.02 to -0.6] vs. -0.06 [-0.09 to +3.3], p = 0.03). Likewise, individuals with lower concentrations of MMP-9 after omalizumab (n = 7, 58%) had a greater reduction in the RBM layer as compared to those with steady MMP-9 levels (-1.8 [-2.4 to -1.14] vs. -0.13 [-0.6 to -0.06] µm, p = 0.03). Moreover, the latter group also had unfavorable higher collagen I accumulation after biologic (42 [20 to 55] vs. 0 [-10 to 20]%, respectively, p = 0.03). Higher concentrations of MMPs in BAL at baseline were related to the lower systemic steroid dose and better omalizumab response concerning the decline in RBM thickness. CONCLUSION: Our data suggest that omalizumab therapy is associated with decreased BAL MMPs concentration in the subgroup of asthma patients. The decline was linked with a reduction in the RBM thickness what might play a beneficial role in airway remodeling.

Heterogeneity of lower airway inflammation in patients with NSAID-exacerbated respiratory disease.

BACKGROUND: Nonsteroidal anti-inflammatory drug (NSAID)-exacerbated respiratory disease (N-ERD) asthma is characterized by chronic rhinosinusitis and intolerance of aspirin and other COX1 inhibitors. Clinical data point to a heterogeneity within the N-ERD phenotype. OBJECTIVE: Our aim was to investigate immune mediator profiles in the lower airways of patients with N-ERD. METHODS: Levels of cytokines (determined by using Luminex assay) and eicosanoids (determined by using mass spectrometry) were measured in bronchoalveolar lavage fluid (BALF) from patients with N-ERD (n = 22), patients with NSAID-tolerant asthma (n = 21), and control subjects (n = 11). mRNA expression in BALF cells was quantified by using TaqMan low-density arrays. RESULTS: Lower airway eosinophilia was more frequent in N-ERD (54.5%) than in NSAID-tolerant asthma (9.5% [P = .009]). The type-2 (T2) immune signature of BALF cells was more pronounced in the eosinophilic subphenotype of N-ERD. Similarly, BALF concentrations of periostin and CCL26 were significantly increased in eosinophilic N-ERD and correlated with T2 signature in BALF cells. Multiparameter analysis of BALF mediators of all patients with asthma revealed the presence of 2 immune endotypes: T2-like (with an elevated level of periostin in BALF) and non-T2/proinflammatory (with higher levels of matrix metalloproteinases and inflammatory cytokines). Patients with N-ERD were classified mostly as having the T2 endotype (68%). Changes in eicosanoid profile (eg, increased leukotriene E4 level) were limited to patients with N-ERD with airway eosinophilia. Blood eosinophilia appeared to be a useful predictor of airway T2 signature (area under the curve [AUC] = 0.83); however, surrogate biomarkers had moderate performance in distinguishing eosinophilic N-ERD (for blood eosinophils, AUC = 0.72; for periostin, AUC = 0.75). CONCLUSIONS: Lower airway immune profiles show considerable heterogeneity of N-ERD, with skewing toward T2 response and eosinophilic inflammation. Increased production of leukotriene E4 was restricted to a subgroup of patients with eosinophilia in the lower airway.

Biomarkers for predicting response to aspirin therapy in aspirin-exacerbated respiratory disease.

BACKGROUND: Aspirin desensitization followed by daily aspirin use is an effective treatment for aspirin-exacerbated respiratory disease (AERD). OBJECTIVE: To assess clinical features as well as genetic, immune, cytological and biochemical biomarkers that might predict a positive response to high-dose aspirin therapy in AERD. METHODS: We enrolled 34 AERD patients with severe asthma who underwent aspirin desensitization followed by 52-week aspirin treatment (650 mg/d). At baseline and at 52 weeks, clinical assessment was performed; phenotypes based on induced sputum cells were identified; eicosanoid, cytokine and chemokine levels in induced sputum supernatant were determined; and induced sputum expression of 94 genes was assessed. Responders to high-dose aspirin were defined as patients with improvement in 5-item Asthma Control Questionnaire score, 22-item Sino-Nasal Outcome Test (SNOT-22) score and forced expiratory volume in 1 second at 52 weeks. RESULTS: There were 28 responders (82%). Positive baseline predictors of response included female sex (p = .002), higher SNOT-22 score (p = .03), higher blood eosinophil count (p = .01), lower neutrophil percentage in induced sputum (p = .003), higher expression of the hydroxyprostaglandin dehydrogenase gene, HPGD (p = .004) and lower expression of the proteoglycan 2 gene, PRG2 (p = .01). The best prediction model included Asthma Control Test and SNOT-22 scores, blood eosinophils and total serum immunoglobulin E. Responders showed a marked decrease in sputum eosinophils but no changes in eicosanoid levels. CONCLUSIONS AND CLINICAL RELEVANCE: Female sex, high blood eosinophil count, low sputum neutrophil percentage, severe nasal symptoms, high HPGD expression and low PRG2 expression may predict a positive response to long-term high-dose aspirin therapy in patients with AERD.

Synthesis and in vitro evaluation of anti-inflammatory, antioxidant, and anti-fibrotic effects of new 8-aminopurine-2,6-dione-based phosphodiesterase inhibitors as promising anti-asthmatic agents.

Phosphodiesterase (PDE) inhibitors are currently an extensively studied group of compounds that can bring many benefits in the treatment of various inflammatory and fibrotic diseases, including asthma. Herein, we describe a series of novel N'-phenyl- or N'-benzylbutanamide and N'-arylidenebutanehydrazide derivatives of 8-aminopurine-2,6-dione (27-43) and characterized them as prominent pan-PDE inhibitors. Most of the compounds exhibited antioxidant and anti-inflammatory activity in lipopolysaccharide (LPS)-induced murine macrophages RAW264.7. The most active compounds (32-35 and 38) were evaluated in human bronchial epithelial cells (HBECs) derived from asthmatics. To better map the bronchial microenvironment in asthma, HBECs after exposure to selected 8-aminopurine-2,6-dione derivatives were incubated in the presence of two proinflammatory and/or profibrotic factors: transforming growth factor type ß (TGF-ß) and interleukin 13 (IL-13). Compounds 32-35 and 38 significantly reduced both IL-13- and TGF-ß-induced expression of proinflammatory and profibrotic mediators, respectively. Detailed analysis of their inhibition preferences for selected PDEs showed high affinity for isoenzymes important in the pathogenesis of asthma, including PDE1, PDE3, PDE4, PDE7, and PDE8. The presented data confirm that structural modifications within the 7 and 8 positions of the purine-2,6-dione core result in obtaining preferable pan-PDE inhibitors which in turn exert an excellent anti-inflammatory and anti-fibrotic effect in the bronchial epithelial cells derived from asthmatic patients. This dual-acting pan-PDE inhibitors constitute interesting and promising lead structures for further anti-asthmatic agent discovery.

Interactions via α2ß1 Cell Integrin May Protect against the Progression of Airway Structural Changes in Asthma.

Increased airway wall thickness and remodeling of bronchial mucosa are characteristic of asthma and may arise from altered integrin signaling on airway cells. Here, we analyzed the expression of ß1-subfamily integrins on blood and airway cells (flow cytometry), inflammatory biomarkers in serum and bronchoalveolar lavage, reticular basement membrane (RBM) thickness and collagen deposits in the mucosa (histology), and airway geometry (CT-imaging) in 92 asthma patients (persistent airflow limitation subtype: n = 47) and 36 controls. Persistent airflow limitation was associated with type-2 inflammation, elevated soluble α2 integrin chain, and changes in the bronchial wall geometry. Both subtypes of asthma showed thicker RBM than control, but collagen deposition and epithelial α1 and α2 integrins staining were similar. Type-I collagen accumulation and RBM thickness were inversely related to the epithelial expression of the α2 integrin chain. Expression of α2ß1 integrin on T-cells and eosinophils was not altered in asthma. Collagen I deposits were, however, more abundant in patients with lower α2ß1 integrin on blood and airway CD8+ T-cells. Thicker airway walls in CT were associated with lower α2 integrin chain on blood CD4+ T-cells and airway eosinophils. Our data suggest that α2ß1 integrin on inflammatory and epithelial cells may protect against airway remodeling advancement in asthma.

Reticular Basement Membrane Thickness Is Associated with Growth- and Fibrosis-Promoting Airway Transcriptome Profile-Study in Asthma Patients.

Airway remodeling in asthma is characterized by reticular basement membrane (RBM) thickening, likely related to epithelial structural and functional changes. Gene expression profiling of the airway epithelium might identify genes involved in bronchial structural alterations. We analyzed bronchial wall geometry (computed tomography (CT)), RBM thickness (histology), and the bronchial epithelium transcriptome profile (gene expression array) in moderate to severe persistent (n = 21) vs. no persistent (n = 19) airflow limitation asthmatics. RBM thickness was similar in the two studied subgroups. Among the genes associated with increased RBM thickness, the most essential were those engaged in cell activation, proliferation, and growth (e.g., CDK20, TACC2, ORC5, and NEK5) and inhibiting apoptosis (e.g., higher mRNA expression of RFN34, BIRC3, NAA16, and lower of RNF13, MRPL37, CACNA1G). Additionally, RBM thickness correlated with the expression of genes encoding extracellular matrix (ECM) components (LAMA3, USH2A), involved in ECM remodeling (LTBP1), neovascularization (FGD5, HPRT1), nerve functioning (TPH1, PCDHGC4), oxidative stress adaptation (RIT1, HSP90AB1), epigenetic modifications (OLMALINC, DNMT3A), and the innate immune response (STAP1, OAS2). Cluster analysis revealed that genes linked with RBM thickness were also related to thicker bronchial walls in CT. Our study suggests that the pro-fibrotic profile in the airway epithelial cell transcriptome is associated with a thicker RBM, and thus, may contribute to asthma airway remodeling.

SARS-CoV-2 may regulate cellular responses through depletion of specific host miRNAs.

Cold viruses have generally been considered fairly innocuous until the appearance of the severe acute respiratory coronavirus 2 (SARS-CoV-2) in 2019, which caused the coronavirus disease 2019 (COVID-19) global pandemic. Two previous viruses foreshadowed that a coronavirus could potentially have devastating consequences in 2002 [severe acute respiratory coronavirus (SARS-CoV)] and in 2012 [Middle East respiratory syndrome coronavirus (MERS-CoV)]. The question that arises is why these viruses are so different from the relatively harmless cold viruses. On the basis of an analysis of the current literature and using bioinformatic approaches, we examined the potential human miRNA interactions with the SARS-CoV-2's genome and compared the miRNA target sites in seven coronavirus genomes that include SARS-CoV-2, MERS-CoV, SARS-CoV, and four nonpathogenic coronaviruses. Here, we discuss the possibility that pathogenic human coronaviruses, including SARS-CoV-2, could modulate host miRNA levels by acting as miRNA sponges to facilitate viral replication and/or to avoid immune responses.

Artificial neural network identifies nonsteroidal anti-inflammatory drugs exacerbated respiratory disease (N-ERD) cohort.

BACKGROUND: To date, there has been no reliable in vitro test to either diagnose or differentiate nonsteroidal anti-inflammatory drug (NSAID)-exacerbated respiratory disease (N-ERD). The aim of the present study was to develop and validate an artificial neural network (ANN) for the prediction of N-ERD in patients with asthma. METHODS: This study used a prospective database of patients with N-ERD (n = 121) and aspirin-tolerant (n = 82) who underwent aspirin challenge from May 2014 to May 2018. Eighteen parameters, including clinical characteristics, inflammatory phenotypes based on sputum cells, as well as eicosanoid levels in induced sputum supernatant (ISS) and urine were extracted for the ANN. RESULTS: The validation sensitivity of ANN was 94.12% (80.32%-99.28%), specificity was 73.08% (52.21%-88.43%), and accuracy was 85.00% (77.43%-92.90%) for the prediction of N-ERD. The area under the receiver operating curve was 0.83 (0.71-0.90). CONCLUSIONS: The designed ANN model seems to have powerful prediction capabilities to provide diagnosis of N-ERD. Although it cannot replace the gold-standard aspirin challenge test, the implementation of the ANN might provide an added value for identification of patients with N-ERD. External validation in a large cohort is needed to confirm our results.

Omalizumab may decrease the thickness of the reticular basement membrane and fibronectin deposit in the bronchial mucosa of severe allergic asthmatics.

Introduction: Immunoglobulin E is an important modulator of the inflammatory reaction in allergic asthma. It also contributes to airway remodeling in the course of the disease. The authors evaluated airway structural changes in severe allergic asthma during the omalizumab therapy. Patients and methods: The study included 13 patients with severe allergic asthma treated with omalizumab for at least one year. In each patient clinical, laboratory, and spirometry parameters were evaluated before and after the treatment. In addition, bronchoscopy with bronchial mucosa biopsy and bronchoalveolar lavage was performed. The basal lamina thickness, inflammatory cell infiltration, fibronectin, as well as type I and III collagen accumulation were assessed in bronchial mucosa specimens, together with the assessment of bronchoalveolar lavage cellularity. Results: The omalizumab therapy led to a decrease in the basal lamina thickness (p = 0.002), and to a reduction in fibronectin (p = 0.02), but not collagen deposits in the bronchial mucosa. The decrease in fibronectin accumulation was associated with an improvement in asthma control and quality of life (p = 0.01, both), and a diminished dose of systemic corticosteroids (p = 0.001). It was also associated with a tendency towards reduction of the eosinophil count in the peripheral blood, bronchoalveolar lavage fluid, and bronchial mucosa specimens. Conclusion: Our study has shown that omalizumab, effective in the treatment of severe allergic asthma, may also decrease unfavorable structural airway changes in allergic asthmatics, at least with respect to the fibronectin deposit and an increased thickness of the basal lamina. However, more extensive observational studies are needed to verify the above hypothesis.

Association of interleukin-10 promoter polymorphisms with serofast state after syphilis treatment.

OBJECTIVES: Recent studies suggested that upregulation of anti-inflammatory immune response during early syphilis may be associated with persistence of Treponema pallidum infection despite adequate treatment, resulting in a serofast state. The objective of this study was to determine whether enhanced interleukin (IL)-10-related response during early T. pallidum infection increased the risk of serofast syphilis. METHODS: Two IL10 gene promoter polymorphisms affecting IL-10 production (-1082A>G [rs1800896], -592C>A [rs1800872]) and serum levels of IL-10 were measured in 80 patients with early syphilis before and 6 months after penicillin treatment and in 24 healthy volunteers (control group). RESULTS: After 6 months, patients were stratified based on serological response into two groups: (1) serofast state (n = 28) and (2) serologically cured (n = 52). Pretreatment and post-treatment serum IL-10 levels were significantly higher in patients who remained serofast compared with those who had a serological cure (p<0.001). The GG genotype of the -1082A>G (rs1800896) polymorphism and the CC genotype of the -592C>A (rs1800872) polymorphism were significantly correlated with higher serum IL-10 levels. Moreover, the OR for remaining serofast for carriers of these genotypes was 16.2 (95% CI: 4.1 to 65.0, p<0.0001) and 2.9 (95% CI: 1.4 to 5.9, p=0.002), respectively. CONCLUSIONS: We showed that a pronounced anti-inflammatory immune response may be an important predictor for the serofast state. Additionally, host-related factors such as polymorphisms of immune regulatory genes may influence the risk of remaining serofast after syphilis therapy.

Skewing toward Treg and Th2 responses is a characteristic feature of sustained remission in ANCA-positive granulomatosis with polyangiitis.

The objective of our study was to evaluate the T-helper (Th) and regulatory T (Treg) cell profile in ANCA-positive granulomatosis with polyangiitis (GPA) and its relation to disease activity. In a prospective study, we studied two groups of GPA patients: (i) disease flare (active-GPA, BVAS>6, n = 19), (ii) sustained remission (≥ 1-year prior enrollment, inactive-GPA, BVAS = 0, n = 18). 24 age-sex matched healthy subjects served as controls. Active-GPA patients were followed for 6 months and reevaluated during remission (early remission; n = 13). We analyzed subsets of Th-cells (flow cytometry), production of signature cytokines by in vitro stimulated lymphocytes, and broad spectrum of serum cytokines (Luminex). In all GPA patients we observed expansion of effector Th17 cells, and increased production of IL-17A by in vitro stimulated T cells, as compared to controls. Disease flare was characterized by marked reduction in Treg cells, whereas in sustained remission we showed expansion of both Treg and Th2 subset. Finally, analyzing the cytokine profile, we identified CCL23 and LIGHT, as potential biomarkers of active disease. We conclude that in GPA, expansion of Treg and Th2 lymphocytes in parallel to increased Th17 response is a characteristic feature of sustained remission. In contrast, Treg cells are markedly decreased in disease flare.

Molecular profiling of regulatory T cells in pulmonary sarcoidosis.

BACKGROUND: Sarcoidosis is characterized by exaggerated immune response to unknown agent and can affect different organs. One of the main players in the pathology of the disease are regulatory T cells (Tregs), however, up to date the mechanisms of the possible molecular alterations of this particular cell subset are not known. METHODS: In the current study we looked for the global transcriptomic changes of miRNAs, using predefined array, and mRNAs (RNA seq analysis) of Tregs of patients with the most predominant form of the disease - acute pulmonary sarcoidosis (PS). For this purpose sorted CD4+/CD25+/CD127- Tregs from peripheral blood (PB) and CD4+/CD25 + Tregs from bronchoalveolar lavage (BAL) were used. RESULTS: MiRNA analysis revealed that Tregs isolated from PB and BAL display significantly different miRNA profile, suggesting an important role of the pulmonary microenvironment in creating these changes. Among disease-related miRNAs of PB Tregs we identified miR-155 and miR-223. Moreover, looking at the global transcriptome of PB Tregs, we recognized alterations in TLR-2 signaling pathway and in the downstream of NF-κB apoptosis and proliferation signals. However, induction of TLR-2 expression was found not only in Tregs, but also in the heterogeneous population of peripheral blood mononuclear cells (PBMC) as well as two PBMC subpopulations (CD4+/CD25-and CD4-/CD25-) of patients with PS. This indicates that activation of TLR signaling pathway in sarcoidosis does not occur only in Tregs. CONCLUSION: Our findings offer a deeper insight into the molecular mechanisms of Tregs reduced suppression and increased apoptosis in patients with PS. Based on the current results, future studies should focus on possible therapeutic effect of TLR-2 signaling inhibition.

Connective tissue growth factor regulates transition of primary bronchial fibroblasts to myofibroblasts in asthmatic subjects.

Fibroblast to myofibroblast transition (FMT) contributes to bronchial wall remodelling in persistent asthma. Among other numerous factors involved, transforming growth factor type ß (TGF-ß) plays a pivotal role. Recently it has been demonstrated that connective tissue growth factor (CTGF), a matricellular protein, combines with TGF-ß in the pathomechanism of many fibrotic disorders. However, it is not clear whether this interaction takes place in asthma as well. Primary cultures of human bronchial fibroblasts from asthmatic and non-asthmatic subjects were used to investigate the impact of CTGF and TGF-ß1 on the fibroblast to myofibroblast transition. The combined activity of TGF-ß1 and CTGF resulted in an average of 90% of FMT accomplished in cell lines derived from asthmatics. In this group FMT was highly dependent on the presence of CTGF produced by the cells, as shown by gene silencing experiments with the specific siRNA. Results support the important role of CTGF biosynthesis in the asthmatic bronchi amplifying FMT. This is evidenced by inhibition of TGF-ß1-induced FMT following CTGF silencing in asthmatic bronchial fibroblasts. CTGF is produced by fibroblasts and contributes to the FMT phenomenon in positive loop-back, inducing and boosting TGF-ß1 triggered FMT. Thus, CTGF is a promising target for pharmacological intervention in secondary prevention of bronchial remodelling in asthma.

Regulation of bronchial epithelial barrier integrity by type 2 cytokines and histone deacetylases in asthmatic patients.

BACKGROUND: Tight junctions (TJs) form a barrier on the apical side of neighboring epithelial cells in the bronchial mucosa. Changes in their integrity might play a role in asthma pathogenesis by enabling the paracellular influx of allergens, toxins, and microbes to the submucosal tissue. OBJECTIVE: The regulation of bronchial epithelial TJs by TH2 cells and their cytokines and their involvement in epigenetic regulation of barrier function were investigated. METHODS: The expression, regulation, and function of TJs were determined in air-liquid interface (ALI) cultures of control and asthmatic primary human bronchial epithelial cells (HBECs) by means of analysis of transepithelial electrical resistance, paracellular flux, mRNA expression, Western blotting, and immunofluorescence staining. RESULTS: HBECs from asthmatic patients showed a significantly low TJ integrity in ALI cultures compared with HBECs from healthy subjects. TH2 cell numbers and levels of their cytokines, IL-4 and IL-13, decreased barrier integrity in ALI cultures of HBECs from control subjects but not in HBECs from asthmatic patients. They induced a physical separation of the TJs of adjacent cells in immunofluorescence staining of the TJ molecules occludin and zonula occludens-1. We observed that expression of histone deacetylases (HDACs) 1 and 9, and Silent information regulator genes (sirtuins [SIRTs]) 6 and 7 were significantly high in HBECs from asthmatic patients. IL-4 and IL-13 significantly increased the expression of HDACs and SIRTs. The role of HDAC activation on epithelial barrier leakiness was confirmed by HDAC inhibition, which improved barrier integrity through increased synthesis of TJ molecules in epithelium from asthmatic patients to the level seen in HBECs from control subjects. CONCLUSION: Our data demonstrate that barrier leakiness in asthmatic patients is induced by TH2 cells, IL-4, and IL-13 and HDAC activity. The inhibition of endogenous HDAC activity reconstitutes defective barrier by increasing TJ expression.

Robust pro-inflammatory immune response is associated with serological cure in patients with syphilis: an observational study.

OBJECTIVES: Approximately 15% of adequately treated patients with early syphilis remain serofast. Pathogenesis and clinical significance of this phenomenon is unclear. The objective of this study was to determine whether there is any association between host immune response and treatment outcome (serofast state or proper serological response). METHODS: Forty-four patients with secondary syphilis were enrolled to this study. Levels of pro-inflammatory cytokines such as interferon-γ, tumour necrosis factor-α and interleukin-6 were measured before treatment and 8 hours after injection of antibiotic. RESULTS: After 1 year, based on the serological response patients were stratified into two groups: (1) proper serological response (n=31) and (2) serofast state (n=9). The serological cure rate was 77.5% at 12 months after treatment. Patients with proper serological response had significantly higher levels of analysed cytokines (at baseline and 8 hours after treatment) compared with the serofast state group (p<0.05). CONCLUSIONS: We showed that robust host pro-inflammatory immune response to infection may be the predictive factor of serological cure. The treatment outcome may be also associated with the magnitude of immune reaction occurring during the treatment.

miR-200b downregulates CFTR during hypoxia in human lung epithelial cells.

BACKGROUND: Hypoxic conditions induce the expression of hypoxia-inducible factors (HIFs) that allow cells to adapt to the changing conditions and alter the expression of a number of genes including the cystic fibrosis transmembrane conductance regulator (CFTR). CFTR is a low abundance mRNA in airway epithelial cells even during normoxic conditions, but during hypoxia its mRNA expression decreases even further. METHODS: In the current studies, we examined the kinetics of hypoxia-induced changes in CFTR mRNA and protein levels in two human airway epithelial cell lines, Calu-3 and 16HBE14o-, and in normal primary bronchial epithelial cells. Our goal was to examine the posttranscriptional modifications that affected CFTR expression during hypoxia. We utilized in silico predictive protocols to establish potential miRNAs that could potentially regulate CFTR message stability and identified miR-200b as a candidate molecule. RESULTS: Analysis of each of the epithelial cell types during prolonged hypoxia revealed that CFTR expression decreased after 12 h during a time when miR-200b was continuously upregulated. Furthermore, manipulation of the miRNA levels during normoxia and hypoxia using miR-200b mimics and antagomirs decreased and increased CFTR mRNA levels, respectively, and thus established that miR-200b downregulates CFTR message levels during hypoxic conditions. CONCLUSION: The data suggest that miR-200b may be a suitable target for modulating CFTR levels in vivo.