Th2-skewed peripheral T-helper cells drive B-cells in allergic bronchopulmonary aspergillosis.

INTRODUCTION: Patients with allergic bronchopulmonary aspergillosis (ABPA) suffer from repeated exacerbations. The involvement of T-cell subsets remains unclear. METHODS: We enrolled ABPA patients, asthma patients and healthy controls. T-helper type 1 (Th1), 2 (Th2) and 17 (Th17) cells, regulatory T-cells (Treg) and interleukin (IL)-21+CD4+T-cells in total or sorted subsets of peripheral blood mononuclear cells and ABPA bronchoalveolar lavage fluid (BALF) were analysed using flow cytometry. RNA sequencing of subsets of CD4+T-cells was done in exacerbated ABPA patients and healthy controls. Antibodies of T-/B-cell co-cultures in vitro were measured. RESULTS: ABPA patients had increased Th2 cells, similar numbers of Treg cells and decreased circulating Th1 and Th17 cells. IL-5+IL-13+IL-21+CD4+T-cells were rarely detected in healthy controls, but significantly elevated in the blood of ABPA patients, especially the exacerbated ones. We found that IL-5+IL-13+IL-21+CD4+T-cells were mainly peripheral T-helper (Tph) cells (PD-1+CXCR5-), which also presented in the BALF of ABPA patients. The proportions of circulating Tph cells were similar among ABPA patients, asthma patients and healthy controls, while IL-5+IL-13+IL-21+ Tph cells significantly increased in ABPA patients. Transcriptome data showed that Tph cells of ABPA patients were Th2-skewed and exhibited signatures of follicular T-helper cells. When co-cultured in vitro, Tph cells of ABPA patients induced the differentiation of autologous B-cells into plasmablasts and significantly enhanced the production of IgE. CONCLUSION: We identified a distinctly elevated population of circulating Th2-skewed Tph cells that induced the production of IgE in ABPA patients. It may be a biomarker and therapeutic target for ABPA.

Fractional exhaled nitric oxide, a potential biomarker for evaluating glucocorticoids treatment and prognosis in allergic bronchopulmonary aspergillosis.

BACKGROUND: Allergic bronchopulmonary aspergillosis (ABPA) is characterized by enhanced TH2 inflammatory response. Fractional exhaled nitric oxide (FeNO) measurement has been used as a valuable tool in predicting the development and management of asthma, another typical TH2 inflammation. However, the clinical significance of FeNO in ABPA remains unclear. OBJECTIVE: To investigate the association between FeNO and the prognosis of patients with ABPA to provide a basis for the use of FeNO in evaluating the efficacy of glucocorticoids in ABPA treatment. METHODS: This study comprised 2 parts; 58 patients were enrolled in the retrospective study. Clinical indexes in patients with different prognoses were compared, and receiver operating characteristic curve analysis was used to determine the threshold value. The prospective observational study involved 61 patients who were regularly followed up at 4 to 6 weeks and 6 months since the initial treatment. Patients were grouped on the basis of baseline FeNO values; correlation analysis was performed in the clinical data. RESULTS: Different prognoses were observed between patients with high and low baseline FeNO values, with a threshold value of 57 parts per billion. The percentage of Aspergillus fumigatus-specific IgE, percentage of positive A fumigatus-specific IgG, and relapse/exacerbation rate differed significantly between the high and low FeNO groups. Patients with higher FeNO needed longer treatment duration and showed shorter interval between glucocorticoid withdrawal and the next relapse/exacerbation. CONCLUSION: Our findings indicate that the level of FeNO is associated with the prognosis of ABPA. It can serve as an independent and valuable biomarker for evaluating the effectiveness of glucocorticoid treatment.

The role of pirfenidone in the treatment of interstitial pneumonia with autoimmune features.

OBJECTIVES: No approved pharmacotherapies are available for patients with interstitial pneumonia with autoimmune features (IPAF). In the present work, we aimed to evaluate the efficacy and safety of pirfenidone for the treatment of IPAF. METHODS: A retrospective cohort study consisting of patients who met diagnostic criteria for IPAF was performed after a multidisciplinary review, and the patients receiving pirfenidone were compared with those in the non-pirfenidone group. The baseline data and diagnostic characteristics of patients were assessed. Pulmonary function and prednisone dose were analysed by a mix-effects model. RESULTS: A total of 184 patients, who met the diagnostic criteria of IPAF, were divided into two groups: pirfenidone group (n=81) and non-pirfenidone group (n=103). Patients in the pirfenidone group had a lower forced vital capacity (FVC%, p<0.001) and a lower diffusion capacity for carbon monoxide (DLCO%, p=0.003). The pirfenidone group exhibited a greater increase of FVC% at 6 (p=0.003), 12 (p=0.013), and 24 (p=0.003) months. After adjustment for sex, age, UIP pattern, baseline FVC% and DLCO%, patients in the pirfenidone group continued to show a greater improvement in FVC% (χ2(1)=4.59, p=0.032). Subgroup analysis identified superior therapeutic effects of pirfenidone in patients with dosage >600 mg/day (p=0.010) and medication course >12 months (p=0.007). Besides, the pirfenidone group had a lower prednisone dose than the non-pirfenidone group after 12 months of treatment (p=0.002). Moreover, 17 patients (19.32%) experienced side effects after taking pirfenidone, including one case of anaphylactic shock. CONCLUSIONS: Pirfenidone (600-1,800 mg/day) might help improve FVC, with an acceptable safety and tolerability profile in IPAF patients.

Cigarette smoke-initiated autoimmunity facilitates sensitisation to elastin-induced COPD-like pathologies in mice.

It is currently not understood whether cigarette smoke exposure facilitates sensitisation to self-antigens and whether ensuing auto-reactive T cells drive chronic obstructive pulmonary disease (COPD)-associated pathologies.To address this question, mice were exposed to cigarette smoke for 2 weeks. Following a 2-week period of rest, mice were challenged intratracheally with elastin for 3 days or 1 month. Rag1-/- , Mmp12-/- , and Il17a-/- mice and neutralising antibodies against active elastin fragments were used for mechanistic investigations. Human GVAPGVGVAPGV/HLA-A*02:01 tetramer was synthesised to assess the presence of elastin-specific T cells in patients with COPD.We observed that 2 weeks of cigarette smoke exposure induced an elastin-specific T cell response that led to neutrophilic airway inflammation and mucus hyperproduction following elastin recall challenge. Repeated elastin challenge for 1 month resulted in airway remodelling, lung function decline and airspace enlargement. Elastin-specific T cell recall responses were dose dependent and memory lasted for over 6 months. Adoptive T cell transfer and studies in T cells deficient Rag1-/- mice conclusively implicated T cells in these processes. Mechanistically, cigarette smoke exposure-induced elastin-specific T cell responses were matrix metalloproteinase (MMP)12-dependent, while the ensuing immune inflammatory processes were interleukin 17A-driven. Anti-elastin antibodies and T cells specific for elastin peptides were increased in patients with COPD.These data demonstrate that MMP12-generated elastin fragments serve as a self-antigen and drive the cigarette smoke-induced autoimmune processes in mice that result in a bronchitis-like phenotype and airspace enlargement. The study provides proof of concept of cigarette smoke-induced autoimmune processes and may serve as a novel mouse model of COPD.

Therapeutic effect of subcutaneous injection of low dose recombinant human granulocyte-macrophage colony-stimulating factor on pulmonary alveolar proteinosis.

OBJECTIVE: To observe the efficacy of recombinant human granulocyte-macrophage colony-stimulating factor (rhGM-CSF) for pulmonary alveolar proteinosis (PAP). MATERIALS AND METHODS: A total of 55 patients with PAP were screened at Shanghai Pulmonary Hospital between May 2014 and May 2018. Among these, 42 were diagnosed with idiopathic PAP, 24 were included in this study, 20 were treated for 6 months, and 17 were followed up for additional 6 months. All patients received a subcutaneous injection of 75µg/d GM-CSF qd for 1 month. The therapeutic dose was adjusted according to the changes in the lesions of chest CT. If the lesions were absorbed, subcutaneous injections of 75µg/d GM- CSF qd and 75µg/d GM-CSF qod were given for 2 and 3 months, otherwise, the dose was increased to 150µg/d GM-CSF qd and 150µg/d qod for 2 and 3 months, respectively. All cases were treated once a day in the first 3 months and once every other day in the last 3 months. The total course of treatment was 6 months. After withdrawal, the patients were followed up for another 6 months. The deadline of follow up was September 30, 2019. RESULTS: Twenty patients completed the treatment and efficacy evaluation. One patient was completely cured, 16 cases improved, three cases were noneffective. After 1-month evaluation, 12 patients received an increased dose (150µg) from the second month of treatment. Seventeen patients completed the 12-month follow-up, among which fourteen improved. CT showed the lesions were slightly increased in three cases. Economic burden was the following: RMB 7324-15,190 Yuan were required for the 6-month treatment course, which is significantly lower compared to other treatment methods. CONCLUSION: Subcutaneous injection of rhGM-CSF at low dose (75µg-150µg /d) is effective treatment for patients with idiopathic PAP. TRIAL REGISTRATION: NCT01983657. Registered 16 April 2013.

IL-17A contributes to HSV1 infection-induced acute lung injury in a mouse model of pulmonary fibrosis.

BACKGROUND: Patients with idiopathic pulmonary fibrosis (IPF) often experience acute exacerbation (AE) after an episode of common cold. AIMS: To establish a mouse model of virus infection-induced AE-IPF and investigate the mechanism underlying the AE-IPF. METHODS: Herpes simplex virus 1 (HSV1) was inoculated intranasally to wild-type (WT) and IL-17A gene knockout (IL-17A-/- ) mice 21 days after intratracheal administration of bleomycin (BLM). RESULTS: HSV1 infection caused acute exacerbation in mice with BLM-induced fibrosis. Compared with the BLM+Saline mice, the mice with BLM+HSV1 showed significantly higher acute lung injury (ALI) score (P < 0.0001), lower survival rate (100% vs 21.4%, P < 0.0001), poorer lung function and higher inflammatory response representing by increased total inflammatory cells in bronchoalveolar lavage fluid (BALF) (P = 0.0323), increased proportion of Th17 cells in peripheral blood (P = 0.0004) and higher inflammatory factors in BALF. In addition, HSV1 infection increased the expression of endoplasmic reticulum stress (ERS)-related proteins in mice with BLM-induced fibrosis. The inhibition of ERS by tauroursodeoxycholic acid (TUDCA, an ERS inhibitor) significantly reduced the IL-17A levels in BALF (P = 0.0140) and TH17 cells in the peripheral blood (P = 0.0084) of mice with BLM+HSV1, suggesting that suppression of ERS may reduce TH17 response in mice with AE-IPF. Compared with WT mice with BLM+HSV1, IL-17A-/- mice with BLM+HSV1 had lower ALI score (P = 0.0119), higher survival rate (78.6% vs 21.4%, P = 0.004), improved lung function, and milder inflammatory response. CONCLUSIONS: HSV1 infection in addition to BLM-induced IPF can successfully establish AE-IPF in mice. IL-17A and ERS promote lung inflammation in AE-IPF development.

The Role of Infection in Acute Exacerbation of Idiopathic Pulmonary Fibrosis.

BACKGROUND: Acute exacerbation of IPF (AE-IPF) is associated with high mortality. We studied changes in pathogen involvement during AE-IPF and explored a possible role of infection in AE-IPF. OBJECTIVES: Our purpose is to investigate the role of infection in AE-IPF. METHODS: Overall, we recruited 170 IPF patients (48 AE-IPF, 122 stable) and 70 controls at Shanghai Pulmonary Hospital. Specific IgM against microbial pathogens and pathogens in sputum were assessed. RNA sequences of pathogens in nasopharyngeal swab of IPF patients were detected by PathChip. A panel of serum parameters reflecting immune function were assessed. RESULTS: Antiviral/bacterial IgM was higher in IPF vs. controls and in AE-IPF vs. stable IPF. Thirty-eight different bacterial strains were detected in IPF patient sputum. Bacteria-positive results were found in 9/48 (18.8%) of AE-IPF and in 26/122 (21.3%) stable IPF. Fifty-seven different viruses were detected in nasopharyngeal swabs of IPF patients. Virus-positive nasopharyngeal swabs were found in 18/30 (60%) of tested AE-IPF and in 13/30 (43.3%) of stable IPF. AE-IPF showed increased inflammatory cytokines (IL-6, IFN-γ, MIG, IL-17, and IL-9) vs. stable IPF and controls. Mortality of AE-IPF in one year (39.5%) was higher compared to stable IPF (28.7%).Conclusions. IPF patients had different colonization with pathogens in sputum and nasopharyngeal swabs; they also displayed abnormally activated immune response, which was exacerbated during AE-IPF.

Impact of Magnetic Resonance Imaging on Treatment-Related Decision Making for Osteoporotic Vertebral Compression Fracture: A Prospective Randomized Trial.

BACKGROUND The aim of this study was to analyze the impact and usefulness of characteristic signal change of a linear black signal on magnetic resonance imaging (MRI) on treatment-related decision making. MATERIAL AND METHODS Forty-one patients with a linear black signal on MRI were enrolled in this prospective study. They were randomly divided into the percutaneous kyphoplasty (PKP) group (n=24) and the conservative treatment group (n=17). Clinical measures, including visual analog scale (VAS) and short-form 36 (SF-36) questionnaire, were analyzed. Radiographic measures, including anterior vertebral body height, kyphosis angle and rate of bone-union, were evaluated. RESULTS VAS scores were significantly lower in the PKP group than in the conservative treatment group post-treatment and at one-year follow-up. After one year of treatment, the values for physical functioning, physical health, and body pain were significantly higher in the PKP group than in the conservative treatment group (p<0.05). The PKP group had a significantly higher anterior vertebral body height, rate of bone-union, and lower kyphosis angle than the conservative treatment group at one-year follow-up (p<0.05). CONCLUSIONS In patients with a linear black signal detected on MRI, the first-choice treatment should be PKP rather than conservative treatment.

High throughput 16SrRNA gene sequencing reveals the correlation between Propionibacterium acnes and sarcoidosis.

OBJECTIVE: This study aims to use high throughput 16SrRNA gene sequencing to examine the bacterial profile of lymph node biopsy samples of patients with sarcoidosis and to further verify the association between Propionibacterium acnes (P. acnes) and sarcoidosis. METHODS: A total of 36 mediastinal lymph node biopsy specimens were collected from 17 cases of sarcoidosis, 8 tuberculosis (TB group), and 11 non-infectious lung diseases (control group). The V4 region of the bacterial 16SrRNA gene in the specimens was amplified and sequenced using the high throughput sequencing platform MiSeq, and bacterial profile was established. The data analysis software QIIME and Metastats were used to compare bacterial relative abundance in the three patient groups. RESULTS: Overall, 545 genera were identified; 38 showed significantly lower and 29 had significantly higher relative abundance in the sarcoidosis group than in the TB and control groups (P < 0.01). P. acnes 16SrRNA was exclusively found in all the 17 samples of the sarcoidosis group, whereas was not detected in the TB and control groups. The relative abundance of P. acnes in the sarcoidosis group (0.16% ± 0. 11%) was significantly higher than that in the TB (Metastats analysis: P = 0.0010, q = 0.0044) and control groups (Metastats analysis: P = 0.0010, q = 0.0038). The relative abundance of P. granulosum was only 0.0022% ± 0. 0044% in the sarcoidosis group. P. granulosum 16SrRNA was not detected in the other two groups. CONCLUSION: High throughput 16SrRNA gene sequencing appears to be a useful tool to investigate the bacterial profile of sarcoidosis specimens. The results suggest that P. acnes may be involved in sarcoidosis development.

IL-10-Producing B Cells Suppress Effector T Cells Activation and Promote Regulatory T Cells in Crystalline Silica-Induced Inflammatory Response In Vitro.

Long-term exposure to crystalline silica leads to silicosis, which is characterized by persistent lung inflammation and lung fibrosis. Multiple immune cells have been demonstrated to participate in crystalline silica-induced immune responses. Our previous study indicated that B10 could control lung inflammation through modulating the Th balance in experimental silicosis in mice. However, the regulatory mechanism of B10 on CD4+ T cells is still unclear. MACS-sorted CD19+ B cells from the three different groups were cultured with CD4+ T cells either with or without transwell insert plates to evaluate the effects of B10 on CD4+ T cells, including Teff and Treg. B10 was eliminated by anti-CD22 application in vivo. Flow cytometry was used to test the frequencies of CD4+ T cells, and the expressions of the related cytokines were detected by real-time PCR and CBA. Insufficient B10 elevated the levels of proinflammatory cytokines and promoted Th responses in a way independent upon cell-cell contact in the Teff and B cell coculture system. B10 could both increase Treg activity and enhance conversion of Teff into Treg. Our findings demonstrated that B10 could affect Th responses by the release of IL-10, enhancing Treg functions and converting Teff into Treg.

Establishment of the mouse model of acute exacerbation of idiopathic pulmonary fibrosis.

PURPOSE: To explore and establish an animal model of AE-IPF. METHODS: An animal model of idiopathic pulmonary fibrosis (IPF) was established using bleomycin (BLM). Then, BLM was administered a second time on day 21 to induce AE-IPF (which mimics human AE-IPF). Evaluation of the success of animal model was based on the survival of mice, as well as assessment of pathological changes in lung tissue. Preliminary investigation into the immunological mechanism of AE-IPF was also explored via the detection and identification of the inflammatory cells in mouse bronchoalveolar lavage fluid (BALF) and the concentrations of six cytokines (IL-4, IL-6, IL-10, IL-17A, MIG, and TGF-ß1) in BALF supernatants, which were closely associated with IPF and AE-IPF. The intervention role of IL-17A antibody to AE was explored. RESULTS: By week 4 after the second BLM administration, the mortality in the AE-IPF group was significantly greater (45%, 9/20) than that in stable-IPF group (0/18) (P = .0017). The average body weight in AE-IPF group was significantly lower than that in stable group (P < .0001). In AE-IPF group, inflammation and fibrosis were severer by histopathology analysis. In BALF, IL-17A, MIG (CXCL-9), IL-6, and TGF-ß1 levels in AE group were significantly higher. The percentages of neutrophils and Th17 cells in BALF were significantly higher in AE group (P < .01; P = .0281). IL-17A antibody could attenuated the lung inflammation induced by twice BLM challenges. CONCLUSION: A mouse model of AE-IPF can be established using two administrations of BLM; Th17 cells may play a key role during the pathological process of AE-IPF.

Blockade of Wnt/ß-Catenin Pathway Aggravated Silica-Induced Lung Inflammation through Tregs Regulation on Th Immune Responses.

CD4(+) T cells play an important role in regulating silica-induced inflammation and fibrosis. Recent studies showed that Wnt/ß-catenin pathway could modulate the function and the differentiation of CD4(+) T cells. Therefore, Wnt/ß-catenin pathway may participate in the development and progress of silicosis. To investigate the role of Wnt/ß-catenin pathway, we used lentivirus expressing ß-catenin shRNA to block the Wnt/ß-catenin pathway by intratracheal instillation to the mice model of silicosis. Treatment of lentivirus could significantly aggravate the silica-induced lung inflammation and attenuated the fibrosis at the late stage. By analyzing CD4(+) T cells, we found that blockade of Wnt/ß-catenin pathway suppressed regulatory T cells (Tregs). Reciprocally, enhanced Th17 response was responsible for the further accumulation of neutrophils and production of proinflammatory cytokines. In addition, blockade of Wnt/ß-catenin pathway delayed the Th1/Th2 polarization by inhibiting Tregs and Th2 response. These results indicated that Wnt/ß-catenin pathway could regulate Tregs to modulate Th immune response, which finally altered the pathological character of silicosis. Our study suggested that Wnt/ß-catenin pathway might be a potential target to treat the silica-induced inflammation and fibrosis.

Baicalin Alleviates Silica-Induced Lung Inflammation and Fibrosis by Inhibiting the Th17 Response in C57BL/6 Mice.

Silicosis is an inflammatory and fibrotic lung disease caused by inhalation of silica. Th17 cells play a key role in causing silica-induced lung inflammation and fibrosis. Baicalin, a compound isolated from the Chinese herb Huangqin, could suppress the differentiation of Th17 cells and alleviate inflammation. However, there are very few reports of the immunoregulatory mechanisms of baicalin in experimental silica-induced lung inflammation and fibrosis. In our study, mice were exposed to silica by intratracheal instillation, and in this way we established an experimental silicosis model. To elucidate the effects and mechanisms of baicalin in silica-induced inflammation and fibrosis, we used baicalin to treat the developed mouse model of silicosis. Treatment with baicalin attenuated the accumulation of inflammatory cells and led to milder pathological inflammatory and fibrotic changes in lung tissues. Baicalin affected the immunological balance between Th17 and Treg responses. Therefore, baicalin caused a decrease in Th17 cells by stimulating Treg cells and by inhibiting IL-6 and IL-23. We further demonstrated that silica-induced Th1 and Th2 immune responses were both inhibited by increased Treg activation, which was promoted by baicalin. Our findings confirmed the potential functions of baicalin in inhibiting the Th17 response and reducing silica-induced inflammation and fibrosis.

N-acetylcysteine attenuates cigaret smoke-induced pulmonary exacerbation in a mouse model of emphysema.

OBJECTIVE: The purpose of this study was to investigate the effects of cigaret smoke (CS) on a mouse model of emphysema and examine the protective role of N-acetylcysteine (NAC) in the CS-induced exacerbation of pulmonary damage in the mice. METHOD: Particulate matter (PM) in sidestream cigaret smoke aerosol was analyzed by a scanning mobility particle sizer spectrometer. A mouse model of emphysema was established by an injection of porcine pancreatic elastase (PPE) into the trachea. Mice with emphysema were then exposed to filtered air, or sidestream CS with intragastric administration of NAC or normal saline. Mouse body weight, survival, pulmonary tissue histology, total antioxidant capacity (T-AOC) and malonaldehyde (MDA) contents in lung tissue, and inflammatory responses were examined. RESULTS: Particles with a size of ≤346 nm constituted 99.06% of CS PM. Mice exhibited ruptured alveolar septal, alveolar fusion, significantly increased mean lining interval, and reduced mean alveolar number (all p < 0.05), 21 d after PPE injection. Exposure of mice with emphysema to CS exacerbated the pulmonary tissue damage, caused weight loss, significantly increased mortality, decreased T-AOC, elevated MDA contents in lung tissue, and increased interleukin (IL)-1ß levels in bronchoalveolar lavage (BAL) fluids (all p < 0.05). Administration of NAC attenuated those CS-induced adverse effects in the mice and increased anti-inflammatory factor IL-10 levels in BAL fluids significantly (all p < 0.05). CONCLUSIONS: Exposure of mice with emphysema to CS exacerbated the pulmonary damage, and NAC reduced the CS-mediated pulmonary damage by preventing oxidative damage and reducing inflammatory responses.

Th17 can regulate silica-induced lung inflammation through an IL-1ß-dependent mechanism.

Silicosis is an occupational lung disease caused by the inhalation of silica dust and characterized by lung inflammation and fibrosis. Interleukin (IL)-1ß is induced by silica and functions as the key pro-inflammatory cytokine in this process. The Th17 response, which is induced by IL-1ß, has been reported very important in chronic human lung inflammatory diseases. To elucidate the underlying mechanisms of IL-1ß and IL-17 in silicosis, we used anakinra and an anti-IL-17 monoclonal antibody (mAb) to block the receptor of IL-1ß (IL-RI) and IL-17, respectively, in a mouse model of silicosis. We observed increased IL-1ß expression and an enhanced Th17 response after silica instillation. Treatment with an IL-1 type I receptor (IL-1RI) antagonist anakinra substantially decreased silica-induced lung inflammation and the Th17 response. Lung inflammation and the accumulation of inflammatory cells were attenuated in the IL-17-neutralized silicosis group. IL-17 may promote lung inflammation by modulating the differentiation of Th1 and regulatory T cells (Tregs) and by regulating the production of IL-22 and IL-1ß during the lung inflammation of silicosis. Silica may induce IL-1ß production from alveolar macrophages and promote inflammation by initiating a Th17 response via an IL-1ß/IL-1RI-dependent mechanism. The Th17 response could induce lung inflammation during the pathogenesis of silicosis by regulating the homoeostasis of the Th immune responses and affecting the production of IL-22 and IL-1ß. This study describes a potentially important inflammatory mechanism of silicosis that may bring about novel therapies for this inflammatory and fibrotic disease.

Neutralization of interleukin-17A delays progression of silica-induced lung inflammation and fibrosis in C57BL/6 mice.

Silica exposure can cause lung inflammation and fibrosis, known as silicosis. Interleukin-17A (IL-17A) and Th17 cells play a pivotal role in controlling inflammatory diseases. However, the roles of IL-17A and Th17 cells in the progress of silica-induced inflammation and fibrosis are poorly understood. This study explored the effects of IL-17A on silica-induced inflammation and fibrosis. We used an anti-mouse IL-17A antibody to establish an IL-17A-neutralized mice model, and mice were exposed to silica to establish an experimental silicosis model. We showed that IL-17A neutralization delayed neutrophil accumulation and progression of silica-induced lung inflammation and fibrosis. IL-17A neutralization reduced the percentage of Th17 in CD4+ T cells, decreased IL-6 and IL-1ß expression, and increased Tregs at an early phase of silica-induced inflammation. Neutralization of IL-17A delayed silica-induced Th1/Th2 immune and autoimmune responses. These results suggest that IL-17A neutralization alleviates early stage silica-induced lung inflammation and delays progression of silica-induced lung inflammation and fibrosis. Neutralization of IL-17A suppressed Th17 cell development by decreasing IL-6 and/or IL-1ß and increased Tregs at an early phase of silica-induced inflammation. Neutralization of IL-17A also delayed the Th1/Th2 immune response during silica-induced lung inflammation and fibrosis. IL-17A may play a pivotal role in the early phase of silica-induced inflammation and may mediate the Th immune response to influence silica-induced lung inflammation and fibrosis in mice.

IL-10 negatively regulates oxLDL-P38 pathway inhibited macrophage emigration.

The effect of IL-10 on macrophage migration was investigated, including the analysis of protein expression, cytokine secretion and activation of the MAPKs and NF-kB pathway. The expression of endogenic IL-10 was down-regulated in macrophage stimulated with oxLDL for indicated time. Exogenous IL-10 reversed oxLDL-inhibited chemotactic macrophage numbers by 48.18 ± 4.93% (3h), 64.8 ± 5.61% (6h) and 63.66 ± 3.05% (12h), and pretreated with SB203580 (P38 signaling inhibitor) in macrophage, oxLDL could not inhibit macrophage emigration. IL-10 significantly decreased oxLDL-mediated increase of SR-A expression, and pretreatment with ß-arrestin2 RNAi in macrophage could not change oxLDL-induced SR-A expression. IL-10 also significantly decreased oxLDL-mediated increase of ß-arrestin2 expression, and pre-treated with SR-A RNAi in macrophage, oxLDL could not induce the increase of ß-arrestin2 expression. However, IL-10 significantly reversed oxLDL-mediated inhibition of CCR7 expression about 95.7 8 ± 0.99% (mRNA) and 80.06 ± 19.46% (protein), and pretreated with P38 inhibitor SB203580 in macrophage, oxLDL could not decrease CCR7 expression. IL-10 inhibited oxLDL-mediated inhibition of MMP9 secretion about 74.02 ± 22.35%, and pretreated with P38 inhibitor SB203580 in macrophage, oxLDL could not decrease MMP9 secretion. Treatment with oxLDL increased P38-phosphorylation by 31.88 ± 2.79%, 40.24 ± 5.69% and 30.93 ± 4.66% at 15, 30 and 60 min, respectively, whereas the effect of IL-10 on the expression of phosphorylated P38 was reversed by 49.49 ± 12.12%, 70.93 ± 16.14% and 47.62 ± 6.00% in up-indicated time-points, respectively. From these data, we speculated oxLDL-SR-A-ß-arrestin2-P38-MMP9/CCR7 could play a critical role in the macrophages migration, which was blocked by IL-10 through inhibiting oxLDL uptake.

Reduction of IL-17A might suppress the Th1 response and promote the Th2 response by boosting the function of Treg cells during silica-induced inflammatory response in vitro.

Silica inhalation can induce chronic lung inflammation and fibrosis. Upon silica stimulation, activated macrophages trigger the T-lymphocyte which can differentiate into many different types of Th cells, including the recently discovered Th17 cells. IL-17A, the typical Th17 cytokine, is reported in some inflammatory diseases. However, the role of IL-17A in silica-induced inflammatory response is still not clear. The regulatory mechanism of silica-induced Th17 response also needs to be investigated. So we established a mice primary cell coculture system (macrophage and lymphocyte) to investigate the role of IL-17A in silica-induced inflammatory response in vitro, by using anti-IL-17A mAb and IL-1Ra. Both anti-IL-17A mAb and IL-1Ra decreased the level of IL-17A and increased the function of Treg cells. The Th1 response was suppressed and the Th2 response was promoted by the addition of anti-IL-17A mAb or IL-1Ra. IL-1Ra treatment decreased the level of IL-6, whereas the levels of IL-23 and ROR- γ t were increased. Our study demonstrated that IL-17A reduction altered the pattern of silica-induced Th responses by boosting the function of Treg cells in vitro. Blocking the function of IL-1 signal pathway could suppress the level of IL-17A, which played the major role in modulating silica-induced Th responses in vitro.

Small diameter vascular grafts: progress on electrospinning matrix/stem cell blending approach.

The exploration of the next-generation small diameter vascular grafts (SDVGs) will never stop until they possess high biocompatibility and patency comparable to autologous native blood vessels. Integrating biocompatible electrospinning (ES) matrices with highly bioactive stem cells (SCs) provides a rational and promising solution. ES is a simple, fast, flexible and universal technology to prepare extracellular matrix-like fibrous scaffolds in large scale, while SCs are valuable, multifunctional and favorable seed cells with special characteristics for the emerging field of cell therapy and regenerative medicine. Both ES matrices and SCs are advanced resources with medical application prospects, and the combination may share their advantages to drive the overcoming of the long-lasting hurdles in SDVG field. In this review, the advances on SDVGs based on ES matrices and SCs (including pluripotent SCs, multipotent SCs, and unipotent SCs) are sorted out, and current challenges and future prospects are discussed.

Tourism development influence on environmental quality: how renewable energy use and income matter?

Tourism is a significant economic growth and development source, but it relies heavily on the energy sector and contributes to carbon dioxide (CO2) emissions. This study examines how tourism growth, renewable energy, and real GDP affect CO2 emissions in the BRICS countries. The researchers used panel unit root, Pedroni, and Kao methods to test for a long-run equilibrium relationship among the variables. The results reveal that tourism growth harms CO2 emissions in the long run, with a 1% increase in tourism growth leading to a 0.05% decrease in CO2 emissions. Renewable energy usage also harms CO2 emissions, with a 1% increase in renewable energy leading to a 0.15% decrease in CO2 emissions in the long run. CO2 emissions and real GDP show a U-shaped relationship in the long run, supporting the environmental Kuznets curve hypothesis. This hypothesis suggests that CO2 emissions increase with economic growth at low-income levels but decrease with economic growth at high-income levels. Therefore, the study implies that tourism growth can significantly lower CO2 emissions by promoting renewable energy usage and economic development.