Airway Mucus Hyperconcentration in Non-Cystic Fibrosis Bronchiectasis.

Rationale: Non-cystic fibrosis bronchiectasis is characterized by airway mucus accumulation and sputum production, but the role of mucus concentration in the pathogenesis of these abnormalities has not been characterized.Objectives: This study was designed to: 1) measure mucus concentration and biophysical properties of bronchiectasis mucus; 2) identify the secreted mucins contained in bronchiectasis mucus; 3) relate mucus properties to airway epithelial mucin RNA/protein expression; and 4) explore relationships between mucus hyperconcentration and disease severity.Methods: Sputum samples were collected from subjects with bronchiectasis, with and without chronic erythromycin administration, and healthy control subjects. Sputum percent solid concentrations, total and individual mucin concentrations, osmotic pressures, rheological properties, and inflammatory mediators were measured. Intracellular mucins were measured in endobronchial biopsies by immunohistochemistry and gene expression. MUC5B (mucin 5B) polymorphisms were identified by quantitative PCR. In a replication bronchiectasis cohort, spontaneously expectorated and hypertonic saline-induced sputa were collected, and mucus/mucin concentrations were measured.Measurements and Main Results: Bronchiectasis sputum exhibited increased percent solids, total and individual (MUC5B and MUC5AC) mucin concentrations, osmotic pressure, and elastic and viscous moduli compared with healthy sputum. Within subjects with bronchiectasis, sputum percent solids correlated inversely with FEV1 and positively with bronchiectasis extent, as measured by high-resolution computed tomography, and inflammatory mediators. No difference was detected in MUC5B rs35705950 SNP allele frequency between bronchiectasis and healthy individuals. Hypertonic saline inhalation acutely reduced non-cystic fibrosis bronchiectasis mucus concentration by 5%.Conclusions: Hyperconcentrated airway mucus is characteristic of subjects with bronchiectasis, likely contributes to disease pathophysiology, and may be a target for pharmacotherapy.

IL-10 promotes production of intestinal mucus by suppressing protein misfolding and endoplasmic reticulum stress in goblet cells.

BACKGROUND & AIMS: Protein misfolding and endoplasmic reticulum (ER) stress have been observed in intestinal secretory cells from patients with inflammatory bowel diseases and induce intestinal inflammation in mice. However, it is not clear how immune factors affect ER stress and therefore disease symptoms. METHODS: We analyzed the effects of interleukin (IL)-10 on ER stress in intestinal tissues in wild-type C57BL/6, Winnie, IL-10(-/-), and Winnie × IL-10(+/-) mice. In Winnie mice, misfolding of the intestinal mucin Muc2 initiates ER stress and inflammation. We also analyzed the effects of different inhibitors of IL-10 signaling and the N-glycosylation inhibitor tunicamycin in cultured human LS174T goblet cells. RESULTS: Administration of neutralizing antibodies against IL-10 or its receptor (IL-10R1) to Winnie mice rapidly exacerbated ER stress and intestinal inflammation compared with mice given vehicle (controls). Antibodies against IL-10 also increased accumulation of misfolded Muc2 in the ER of goblet cells of Winnie mice and increased T-cell production of inflammatory cytokines. Winnie × IL-10(+/-) mice and IL-10(-/-) mice with a single Winnie allele each developed more severe inflammation than Winnie mice or IL-10(-/-) mice. Administration of tunicamycin to wild-type mice caused intestinal ER stress, which increased when IL-10R1 was blocked. In LS174T cells, induction of ER stress with tunicamycin and misfolding of MUC2 were reduced by administration of IL-10; this reduction required STAT1 and STAT3. In LS174T cells incubated with tunicamycin, IL-10 up-regulated genes involved in MUC2 folding and in ER-associated degradation and maintained correct folding of MUC2, its transport from the ER, and its O-glycosylation and secretion. CONCLUSIONS: IL-10 prevents protein misfolding and ER stress by maintaining mucin production in goblet cells and helps the intestine preserve the mucus barrier.

Effect of long-term, low-dose erythromycin on pulmonary exacerbations among patients with non-cystic fibrosis bronchiectasis: the BLESS randomized controlled trial.

IMPORTANCE: Macrolide antibiotics such as erythromycin may improve clinical outcomes in non-cystic fibrosis (CF) bronchiectasis, although associated risks of macrolide resistance are poorly defined. OBJECTIVE: To evaluate the clinical efficacy and antimicrobial resistance cost of low-dose erythromycin given for 12 months to patients with non-CF bronchiectasis with a history of frequent pulmonary exacerbations. DESIGN, SETTING, AND PARTICIPANTS: Twelve-month, randomized (1:1), double-blind, placebo-controlled trial of erythromycin in currently nonsmoking, adult patients with non-CF bronchiectasis with a history of 2 or more infective exacerbations in the preceding year. This Australian study was undertaken between October 2008 and December 2011 in a university teaching hospital, with participants also recruited via respiratory physicians at other centers and from public radio advertisements. INTERVENTIONS: Twice-daily erythromycin ethylsuccinate (400 mg) or matching placebo. MAIN OUTCOME MEASURES: The primary outcome was the annualized mean rate of protocol-defined pulmonary exacerbations (PDPEs) per patient. Secondary outcomes included macrolide resistance in commensal oropharyngeal streptococci and lung function. RESULTS: Six-hundred seventy-nine patients were screened, 117 were randomized (58 placebo, 59 erythromycin), and 107 (91.5%) completed the study. Erythromycin significantly reduced PDPEs both overall (mean, 1.29 [95% CI, 0.93-1.65] vs 1.97 [95% CI, 1.45-2.48] per patient per year; incidence rate ratio [IRR], 0.57 [95% CI, 0.42-0.77]; P = .003), and in the prespecified subgroup with baseline Pseudomonas aeruginosa airway infection (mean difference, 1.32 [95% CI, 0.19-2.46]; P = .02). Erythromycin reduced 24-hour sputum production (median difference, 4.3 g [interquartile range [IQR], 1 to 7.8], P = .01) and attenuated lung function decline (mean absolute difference for change in postbronchodilator forced expiratory volume in the first second of expiration, 2.2 percent predicted [95% CI, 0.1% to 4.3%]; P = .04) compared with placebo. Erythromycin increased the proportion of macrolide-resistant oropharyngeal streptococci (median change, 27.7% [IQR, 0.04% to 41.1%] vs 0.04% [IQR, -1.6% to 1.5%]; difference, 25.5% [IQR,15.0% to 33.7%]; P < .001). CONCLUSION AND RELEVANCE: Among patients with non-CF bronchiectasis, the 12-month use of erythromycin compared with placebo resulted in a modest decrease in the rate of pulmonary exacerbations and an increased rate of macrolide resistance. TRIAL REGISTRATION: anzctr.org.au Identifier: ACTRN12609000578202.

Interleukin-22 suppresses major histocompatibility complex II in mucosal epithelial cells.

Major histocompatibility complex (MHC) II is dynamically expressed on mucosal epithelial cells and is induced in response to inflammation and parasitic infections, upon exposure to microbiota, and is increased in chronic inflammatory diseases. However, the regulation of epithelial cell-specific MHC II during homeostasis is yet to be explored. We discovered a novel role for IL-22 in suppressing epithelial cell MHC II partially via the regulation of endoplasmic reticulum (ER) stress, using animals lacking the interleukin-22-receptor (IL-22RA1), primary human and murine intestinal and respiratory organoids, and murine models of respiratory virus infection or with intestinal epithelial cell defects. IL-22 directly downregulated interferon-γ-induced MHC II on primary epithelial cells by modulating the expression of MHC II antigen A α (H2-Aα) and Class II transactivator (Ciita), a master regulator of MHC II gene expression. IL-22RA1-knockouts have significantly higher MHC II expression on mucosal epithelial cells. Thus, while IL-22-based therapeutics improve pathology in chronic disease, their use may increase susceptibility to viral infections.

The interplay between endoplasmic reticulum stress and inflammation.

Endoplasmic reticulum (ER) stress may be both a trigger and consequence of chronic inflammation. Chronic inflammation is often associated with diseases that arise because of primary misfolding mutations and ER stress. Similarly, ER stress and activation of the unfolded protein response (UPR) is a feature of many chronic inflammatory and autoimmune diseases. In this review, we describe how protein misfolding and the UPR trigger inflammation, how environmental ER stressors affect antigen presenting cells and immune effector cells, and present evidence that inflammatory factors exacerbate protein misfolding and ER stress. Examples from both animal models of disease and human diseases are used to illustrate the complex interactions between ER stress and inflammation, and opportunities for therapeutic targeting are discussed. Finally, recommendations are made for future research with respect to the interaction of ER stress and inflammation.

High prevalence of human papillomaviruses in fresh frozen breast cancer samples.

While the etiology of breast cancer remains enigmatic, some recent reports have examined the role of human papillomavirus (HPV) in breast carcinogenesis. The purpose of this study was to determine the prevalence of HPV in breast cancer tissue using PCR analysis and sequencing. Fifty-four (54) fresh frozen breast cancers samples that were removed from a cohort of breast cancer patients were analyzed. Samples were tested for HPV using comprehensive PCR primers, and in situ hybridization was performed on paraffin embedded tissue sections. Findings were correlated with clinical and pathological characteristics. The HPV DNA prevalence in the breast cancer samples was 50% (27/54) with sequence analysis indicating all cases to be positive for HPV-18 type. While HPV patients were slightly younger, no correlation was noted for menopausal status or family history. HPV positive tumors were smaller with earlier T staging and demonstrated lesser nodal involvement compared to HPV negative cancers. In situ hybridization analyses proved negative. The high proportion of HPV positive breast cancers detected in this series using fresh frozen tissues cannot be dismissed, however the role of HPV in breast carcinogenesis remains unclear and may ultimately be ascertained by monitoring future breast cancer incidence amongst women vaccinated against high risk HPV types.

Sphingosine signaling dysfunction in airway cells as a potential contributor to progression from protracted bacterial bronchitis to bronchiectasis in children.

AIM: Protracted bacterial bronchitis (PBB) is considered a potential precursor to bronchiectasis (BE) in some children. We previously showed that alveolar macrophages (AM) from children with PBB or BE have a similar significant defect in phagocytic capacity, with proinflammatory associations. We hypothesized that the mechanisms responsible for this defect involve dysregulation of the sphingosine-1-phosphate (S1P) signaling pathway, as we have found in adult inflammatory lung diseases. METHOD: We employed a Custom TaqMan OpenArray to investigate gene expression of S1P-generating enzymes: sphingosine kinases (SPHK) 1/2, S1P phosphatase 2 (SGPP2), S1P lyase 1 (SGPL1), S1P receptors (S1PR) 1/2/4/5; proinflammatory cytokines TNF-α (TNF) and IFNγ (IFNG), the cytotoxic mediator granzyme B (GZMB), and inflammasomes AIM2 and NLRP3, in bronchoalveolar lavage from 15 children with BE, 15 with PBB and 17 age-matched controls, and determined association with clinical/demographic variables and airway inflammation. RESULT: Significantly increased expression of S1PR1, S1PR2, and SPHK1 was noted in PBB and BE AM vs controls with increased SGPP2 only in PBB. TNF, IFNG, AIM2, and NLRP3 were significantly increased in both disease groups with increased GZMB only in PBB. There were no significant differences in the expression of any other S1P-related mediator between groups. There were significant positive associations between Haemophilus influenzae growth and expression of S1PR1 and NLRP3; between S1PR1 and S1PR2, NLRP3 and IFNG; between S1PR2 and AIM2, SPHK1, and SPHK2; and between SPHK1 and GZMB, IFNG, AIM2, and NLRP3. CONCLUSION: Children with PBB and BE share similar S1P-associated gene expression profiles. AM phagocytic dysfunction and inflammation in these children may occur due to dysregulated S1P signaling.

Multiple Respiratory Microbiota Profiles Are Associated With Lower Airway Inflammation in Children With Protracted Bacterial Bronchitis.

BACKGROUND: Effective management of protracted bacterial bronchitis (PBB) is needed to prevent chronic disease (eg, bronchiectasis). Understanding the contributions of ongoing airway infection and inflammation is important to achieving optimal PBB treatments. The aim of this study was to compare BAL microbiota, bacterial biomass, and inflammatory markers in children with PBB and age-matched control patients. METHODS: BAL was prospectively collected from 28 children with PBB (median age, 1.7 years; range, 0.6-7.4) and 8 control patients (median age, 1.9 years; range, 0.4-4.7). BAL microbiology was determined using culture, 16S ribosomal RNA gene sequencing and bacterial biomass quantification. BAL inflammatory cells, IL-8, and IL-1ß were used to assess lower airway inflammation. RESULTS: Bacterial biomass, neutrophil percentage, IL-8, and IL-1ß levels were significantly higher in children with PBB compared with control patients. BAL microbiota in children with PBB was significantly different to that of control patients (permutational multivariate analysis of variance P = .001) and clustered into four distinct profiles that were either dominated by a respiratory pathogen or contained a more diverse microbiota including Prevotella species. Alpha diversity was unrelated to bacterial biomass, culture of recognized respiratory pathogens, or inflammatory markers. CONCLUSIONS: Neutrophilic inflammation in children with PBB was associated with multiple BAL microbiota profiles. Significant associations between inflammatory markers and bacterial biomass, but not alpha diversity, suggest that inflammation in children with PBB is not driven by single pathogenic species. Understanding the role of the entire respiratory microbiota in PBB pathogenesis may be important to determining whether bacteria other than the recognized pathogens contribute to disease recurrence and progression to bronchiectasis.

Oxidative and endoplasmic reticulum stress in respiratory disease.

Oxidative stress and endoplasmic reticulum (ER) stress are related states that can occur in cells as part of normal physiology but occur frequently in diseases involving inflammation. In this article, we review recent findings relating to the role of oxidative and ER stress in the pathophysiology of acute and chronic nonmalignant diseases of the lung, including infections, cystic fibrosis, idiopathic pulmonary fibrosis and asthma. We also explore the potential of drugs targeting oxidative and ER stress pathways to alleviate disease.

PPARγ is reduced in the airways of non-CF bronchiectasis subjects and is inversely correlated with the presence of Pseudomonas aeruginosa.

BACKGROUND: Chronic airway inflammation in conditions such as cystic fibrosis (CF) and non-CF bronchiectasis is characterised by a predominant neutrophilic inflammatory response, commonly due to the presence of pathogenic bacteria such as Pseudomonas aeruginosa. We hypothesised that down-regulation of the anti-inflammatory nuclear transcription regulator peroxisome proliferator-activated receptor gamma (PPARγ in non-CF bronchiectasis subjects may explain why this exuberant neutrophilic inflammation is able to persist unchecked in the inflamed airway. METHODS: PPARγ gene expression was assessed in bronchoalveolar lavage fluid (BAL) of 35 macrolide naïve non-CF bronchiectasis subjects and compared with that in 20 healthy controls. Human RNA was extracted from pelleted BAL and PPARγ expression was determined by reverse-transcription quantitative PCR. Bacterial DNA was extracted from paired induced sputum and total bacterial load was determined by 16S rRNA qPCR. Quantification of individual bacterial species was achieved by qPCR. RESULTS: PPARγ expression was lower in subjects with non-CF bronchiectasis compared with healthy control subjects (control: 1.00, IQR 0.55-1.44, n = 20 vs. Bronchiectasis: 0.49, IQR 0.12-0.89; n = 35; p<0.001, Mann-Whitney U test). This lower PPARγ expression correlated negatively with Pseudomonas aeruginosa (r = -0.53, n = 31; p = 0.002). No significant association was seen between PPARγ and total bacterial levels or levels Haemophilus influenzae. CONCLUSION: PPARγ is expressed in low levels in the airways of non-CF bronchiectasis subjects, despite an aggressive inflammatory response. This low level PPARγ expression is particularly associated with the presence of high levels of P. aeruginosa, and may represent an intrinsic link with this bacterial pathogen.

Airway cells from protracted bacterial bronchitis and bronchiectasis share similar gene expression profiles.

AIM: Protracted bacterial bronchitis (PBB) is a common cause of prolonged cough in young children, and may be a precursor of bronchiectasis. Bacteria are often present in the lower airways in both PBB and bronchiectasis and may cause persistent infections. However, there is a paucity of information available on the pathogenesis of PBB and the factors associated with persistent bacterial infection and progression to bronchiectasis. This study hypothesised that lung immune cells in recurrent PBB and bronchiectasis differentially express genes related to immune cell dysfunction compared to lung immune cells from control subjects. METHOD: Cells isolated from bronchoalveolar lavage (adult-control and PBB BAL cells) were stimulated with nontypeable Haemophilus influenzae (NTHi), and expression of genes involved in various inflammatory pathways was assessed. RESULT: NTHi induced production of large amounts of IL-1ß, IL-6, and IL-8 in adult-control BAL cells, however BAL cells from PBB airways appeared refractory to NTHi stimulation. BAL cells from PBB and bronchiectasis showed differential expression of several genes relative to control cells, including CCL20, MARCO, CCL24, IL-10, PPAR-γ, CD200R, TREM2, RelB. Expression of genes involved in resolution of inflammation and anti-inflammation response, such as CD200R and IL-10, was associated with the number of pathogenic bacteria found in the airways. CONCLUSION: In summary, we have shown that the expression of genes related to macrophage function and resolution of inflammation are similar in PBB and bronchiectasis. Lung immune cell dysfunction in PBB and bronchiectasis may contribute to poor bacterial clearance and prolonged resolution of inflammation.

Multiple inflammasomes may regulate the interleukin-1-driven inflammation in protracted bacterial bronchitis.

Protracted bacterial bronchitis (PBB) in young children is characterised by prolonged wet cough, prominent airway interleukin (IL)-1ß expression and infection, often with nontypeable Haemophilus influenzae (NTHi). The mechanisms responsible for IL-1-driven inflammation in PBB are poorly understood. We hypothesised that the inflammation in PBB involves the NLRP3 and/or AIM2 inflammasome/IL-1ß axis. Lung macrophages obtained from bronchoalveolar lavage (BAL), peripheral blood mononuclear cells (PBMCs), blood monocytes and monocyte-derived macrophages from patients with PBB and age-matched healthy controls were cultured in control medium or exposed to live NTHi. In healthy adult PBMCs, CD14+ monocytes contributed to 95% of total IL-1ß-producing cells upon NTHi stimulation. Stimulation of PBB PBMCs with NTHi significantly increased IL-1ß expression (p<0.001), but decreased NLRC4 expression (p<0.01). NTHi induced IL-1ß secretion in PBMCs from both healthy controls and patients with recurrent PBB. This was inhibited by Z-YVAD-FMK (a caspase-1 selective inhibitor) and by MCC950 (a NLRP3 selective inhibitor). In PBB BAL macrophages inflammasome complexes were visualised as fluorescence specks of NLRP3 or AIM2 colocalised with cleaved caspase-1 and cleaved IL-1ß. NTHi stimulation induced formation of specks of cleaved IL-1ß, NLRP3 and AIM2 in PBMCs, blood monocytes and monocyte-derived macrophages. We conclude that both the NLRP3 and AIM2 inflammasomes probably drive the IL-1ß-dominated inflammation in PBB.

Cytokine responses to two common respiratory pathogens in children are dependent on interleukin-1ß.

Protracted bacterial bronchitis (PBB) in young children is a common cause of prolonged wet cough and may be a precursor to bronchiectasis in some children. Although PBB and bronchiectasis are both characterised by neutrophilic airway inflammation and a prominent interleukin (IL)-1ß signature, the contribution of the IL-1ß pathway to host defence is not clear. This study aimed to compare systemic immune responses against common pathogens in children with PBB, bronchiectasis and control children and to determine the importance of the IL-1ß pathway. Non-typeable Haemophilus influenzae (NTHi) stimulation of peripheral blood mononuclear cells (PBMCs) from control subjects (n=20), those with recurrent PBB (n=20) and bronchiectasis (n=20) induced high concentrations of IL-1ß, IL-6, interferon (IFN)-γ and IL-10. Blocking with an IL-1 receptor antagonist (IL-1Ra) modified the cellular response to pathogens, inhibiting cytokine synthesis by NTHi-stimulated PBMCs and rhinovirus-stimulated PBMCs (in a separate PBB cohort). Inhibition of IFN-γ production by IL-1Ra was observed across multiple cell types, including CD3+ T cells and CD56+ NK cells. Our findings highlight the extent to which IL-1ß regulates the cellular immune response against two common respiratory pathogens. While blocking the IL-1ß pathway has the potential to reduce inflammation, this may come at the cost of protective immunity against NTHi and rhinovirus.

Macrolide Treatment Inhibits Pseudomonas aeruginosa Quorum Sensing in Non-Cystic Fibrosis Bronchiectasis. An Analysis from the Bronchiectasis and Low-Dose Erythromycin Study Trial.

RATIONALE: The mechanism by which low-dose macrolide therapy reduces exacerbations in non-cystic fibrosis bronchiectasis is not known. Pseudomonas aeruginosa quorum sensing controls the expression of a range of pathogenicity traits and is inhibited by macrolide in vitro. Quorum sensing inhibition renders P. aeruginosa less pathogenic, potentially reducing its contribution to airway damage. OBJECTIVES: The aim of this study was to determine whether long-term low-dose erythromycin inhibits P. aeruginosa quorum sensing within the airways of patients with non-cystic fibrosis bronchiectasis. METHODS: Analysis was performed on induced sputum from P. aeruginosa-positive subjects at recruitment to the BLESS (Bronchiectasis and Low-Dose Erythromycin Study) trial and after 48 weeks of treatment with erythromycin or placebo. To avoid changes in gene expression during culture, bacterial mRNA was extracted directly from sputum, and the relative expression of functionally critical quorum sensing genes was determined by quantitative polymerase chain reaction. MEASUREMENTS AND MAIN RESULTS: In keeping with the BLESS study, a significant reduction in total exacerbations was seen in this subgroup (placebo: 6, [interquartile range (IQR), 4-8]; erythromycin: 3, [IQR, 3-4]; P = 0.008; Mann-Whitney test). Erythromycin therapy did not change P. aeruginosa bacterial load determined by polymerase chain reaction. A significant reduction was observed in the expression of the quorum sensing genes, lasR (erythromycin: fold change, 0.065 [IQR, 0.01-0.85], n = 11; placebo: fold change, 1.000 [IQR, 0.05-3.05]; P = 0.047, Mann-Whitney U test) and pqsA (erythromycin: fold change, 0.07 [IQR, 0.02-0.25]; placebo: fold change, 1.000 [IQR, 0.21-4.31], P = 0.017, Mann-Whitney U test), after 48 weeks of erythromycin, compared with placebo. CONCLUSIONS: We demonstrate inhibition of P. aeruginosa quorum sensing within the airways of patients with non-cystic fibrosis bronchiectasis receiving long-term, low-dose erythromycin, without a reduction in bacterial load, representing a potential mechanism of therapeutic impact beyond a classical antimicrobial or antiinflammatory pathway.

Is Alveolar Macrophage Phagocytic Dysfunction in Children With Protracted Bacterial Bronchitis a Forerunner to Bronchiectasis?

BACKGROUND: Children with recurrent protracted bacterial bronchitis (PBB) and bronchiectasis share common features, and PBB is likely a forerunner to bronchiectasis. Both diseases are associated with neutrophilic inflammation and frequent isolation of potentially pathogenic microorganisms, including nontypeable Haemophilus influenzae (NTHi), from the lower airway. Defective alveolar macrophage phagocytosis of apoptotic bronchial epithelial cells (efferocytosis), as found in other chronic lung diseases, may also contribute to tissue damage and neutrophil persistence. Thus, in children with bronchiectasis or PBB and in control subjects, we quantified the phagocytosis of airway apoptotic cells and NTHi by alveolar macrophages and related the phagocytic capacity to clinical and airway inflammation. METHODS: Children with bronchiectasis (n = 55) or PBB (n = 13) and control subjects (n = 13) were recruited. Alveolar macrophage phagocytosis, efferocytosis, and expression of phagocytic scavenger receptors were assessed by flow cytometry. Bronchoalveolar lavage fluid interleukin (IL) 1ß was measured by enzyme-linked immunosorbent assay. RESULTS: For children with PBB or bronchiectasis, macrophage phagocytic capacity was significantly lower than for control subjects (P = .003 and P < .001 for efferocytosis and P = .041 and P = .004 for phagocytosis of NTHi; PBB and bronchiectasis, respectively); median phagocytosis of NTHi for the groups was as follows: bronchiectasis, 13.7% (interquartile range [IQR], 11%-16%); PBB, 16% (IQR, 11%-16%); control subjects, 19.0% (IQR, 13%-21%); and median efferocytosis for the groups was as follows: bronchiectasis, 14.1% (IQR, 10%-16%); PBB, 16.2% (IQR, 14%-17%); control subjects, 18.1% (IQR, 16%-21%). Mannose receptor expression was significantly reduced in the bronchiectasis group (P = .019), and IL-1ß increased in both bronchiectasis and PBB groups vs control subjects. CONCLUSIONS: A reduced alveolar macrophage phagocytic host response to apoptotic cells or NTHi may contribute to neutrophilic inflammation and NTHi colonization in both PBB and bronchiectasis. Whether this mechanism also contributes to the progression of PBB to bronchiectasis remains unknown.

Matrix metalloproteinases vary with airway microbiota composition and lung function in non-cystic fibrosis bronchiectasis.

RATIONALE: Despite growing evidence for the roles of airway remodeling and bacterial infection in the progression of non-cystic fibrosis bronchiectasis, relationships between collagen-degrading proteases and chronic airway infection are poorly understood. OBJECTIVES: The aim of this study was to determine which matrix metalloproteinases (MMPs) are elevated in bronchiectasis, whether these MMP levels vary based on patients' dominant infective microbe, and how these levels correlate with clinical measures of disease severity. METHODS: We determined concentrations of nine MMPs and four tissue inhibitors of metalloproteinases (TIMPs) in induced sputum from 86 patients with bronchiectasis and 8 healthy control subjects by Luminex protein assay. Concentrations were then assessed in relation to lung function, inflammatory markers, and airway microbiota composition, determined by 16S rRNA gene amplicon sequencing. Airway microbiota composition was classified as Pseudomonas aeruginosa-dominated, Haemophilus influenzae-dominated, or dominated by another species. MMP-8 and MMP-9 activity levels were also measured in a subset of patients. MEASUREMENTS AND MAIN RESULTS: MMP-1, -3, -7, -8, and -9 and TIMP-2 and -4 levels, as well as MMP-8/TIMP-1 and MMP-9/TIMP-1 ratios, were significantly higher in patients with bronchiectasis than in healthy control subjects (all: P < 0.001, except MMP-7: P < 0.05). Patients with bronchiectasis with H. influenzae-dominated airway infections demonstrated higher MMP-2 levels (P < 0.01) and MMP-8 activity (P < 0.05) than those with P. aeruginosa-dominated airway infections. Among patients with bronchiectasis, there were significant inverse correlations between FEV1 as a percentage of predicted value, MMP-8 and MMP-1 levels, and MMP-8/TIMP-1 and MMP-9/TIMP-1 ratios (P < 0.01). CONCLUSIONS: Increased MMP levels (particularly MMP-8 and MMP-1) and MMP/TIMP ratios in patients with bronchiectasis compared with healthy control subjects correlated with lower lung function and higher levels of inflammatory markers. Further, MMP profiles differed in patients with bronchiectasis according to the dominant pathogen determined by gene sequencing, raising the possibility of differential airway remodeling according to airway microbiology.

Adult non-cystic fibrosis bronchiectasis is characterised by airway luminal Th17 pathway activation.

BACKGROUND: Non-cystic fibrosis (CF) bronchiectasis is characterised by chronic airway infection and neutrophilic inflammation, which we hypothesised would be associated with Th17 pathway activation. METHODS: Th17 pathway cytokines were quantified in bronchoalveolar lavage fluid (BALF), and gene expression of IL-17A, IL-1ß, IL-8 and IL-23 determined from endobronchial biopsies (EBx) in 41 stable bronchiectasis subjects and 20 healthy controls. Relationships between IL-17A levels and infection status, important clinical measures and subsequent Pseudomonas aeruginosa infection were determined. RESULTS: BALF levels of all Th17 cytokines (median (IQR) pg/mL) were significantly higher in bronchiectasis than control subjects, including IL-17A (1.73 (1.19, 3.23) vs. 0.27 (0.24, 0.35), 95% CI 1.05 to 2.21, p<0.0001) and IL-23 (9.48 (4.79, 15.75) vs. 0.70 (0.43, 1.79), 95% CI 4.68 to 11.21, p<0.0001). However, BALF IL-17A levels were not associated with clinical measures or airway microbiology, nor predictive of subsequent P. aeruginosa infection. Furthermore, gene expression of IL-17A in bronchiectasis EBx did not differ from control. In contrast, gene expression (relative to medians of controls) in bronchiectasis EBx was significantly higher than control for IL1ß (4.12 (1.24, 8.05) vs 1 (0.13, 2.95), 95% CI 0.05 to 4.07, p = 0.04) and IL-8 (3.75 (1.64, 11.27) vs 1 (0.54, 3.89), 95% CI 0.32 to 4.87, p = 0.02) and BALF IL-8 and IL-1α levels showed significant relationships with clinical measures and airway microbiology. P. aeruginosa infection was associated with increased levels of IL-8 while Haemophilus influenzae was associated with increased IL-1α. CONCLUSIONS AND CLINICAL RELEVANCE: Established adult non-CF bronchiectasis is characterised by luminal Th17 pathway activation, however this pathway may be relatively less important than activation of non-antigen-specific innate neutrophilic immunity.

A novel microbiota stratification system predicts future exacerbations in bronchiectasis.

RATIONALE: Although airway microbiota composition correlates with clinical measures in non-cystic fibrosis bronchiectasis, these data are unlikely to provide useful prognostic information at the individual patient level. A system enabling microbiota data to be applied clinically would represent a substantial translational advance. OBJECTIVES: This study aims to determine whether stratification of patients according to the predominant microbiota taxon can provide improved clinical insight compared with standard diagnostics. METHODS: The presence of bacterial respiratory pathogens was assessed in induced sputum from 107 adult patients by culture, quantitative PCR, and, in 96 samples, by ribosomal gene pyrosequencing. Prospective analysis was performed on samples from 42 of these patients. Microbiological data were correlated with concurrent clinical measures and subsequent outcomes. MEASUREMENTS AND MAIN RESULTS: Microbiota analysis defined three groups: Pseudomonas aeruginosa dominated (n = 26), Haemophilus influenzae dominated (n = 34), and other taxa dominated (n = 36). Patients with P. aeruginosa- and H. influenzae-dominated communities had significantly worse lung function, higher serum levels of C-reactive protein (CRP), and higher sputum levels of IL-8 and IL-1ß. Predominance of P. aeruginosa, followed by Veillonella species, was the best predictor of future exacerbation frequency, with H. influenzae-dominated communities having significantly fewer episodes. Detection of P. aeruginosa was associated with poor lung function and exacerbation frequency, irrespective of analytical strategy. Quantitative PCR revealed significant correlations between H. influenzae levels and sputum IL-8, IL-1ß, and serum CRP. Genus richness was negatively correlated with 24-hour sputum weight, age, serum CRP, sputum IL-1ß, and IL-8. CONCLUSIONS: Stratification of patients with non-cystic fibrosis bronchiectasis on the basis of predominant bacterial taxa is more clinically informative than either conventional culture or quantitative PCR-based analysis. Further investigation is now required to assess the mechanistic basis of these associations.

Glycemic control in diabetes is restored by therapeutic manipulation of cytokines that regulate beta cell stress.

In type 2 diabetes, hyperglycemia is present when an increased demand for insulin, typically due to insulin resistance, is not met as a result of progressive pancreatic beta cell dysfunction. This defect in beta cell activity is typically characterized by impaired insulin biosynthesis and secretion, usually accompanied by oxidative and endoplasmic reticulum (ER) stress. We demonstrate that multiple inflammatory cytokines elevated in diabetic pancreatic islets induce beta cell oxidative and ER stress, with interleukin-23 (IL-23), IL-24 and IL-33 being the most potent. Conversely, we show that islet-endogenous and exogenous IL-22, by regulating oxidative stress pathways, suppresses oxidative and ER stress caused by cytokines or glucolipotoxicity in mouse and human beta cells. In obese mice, antibody neutralization of IL-23 or IL-24 partially reduced beta cell ER stress and improved glucose tolerance, whereas IL-22 administration modulated oxidative stress regulatory genes in islets, suppressed ER stress and inflammation, promoted secretion of high-quality efficacious insulin and fully restored glucose homeostasis followed by restitution of insulin sensitivity. Thus, therapeutic manipulation of immune regulators of beta cell stress reverses the hyperglycemia central to diabetes pathology.

Human papillomavirus in benign prostatic hyperplasia and prostatic adenocarcinoma patients.

The aim of this study was to determine the prevalence of human papillomavirus (HPV) types in tissue and HPV antibodies in prostatic disease. Prostate tissue samples were collected from 51 patients diagnosed with adenocarcinoma and 11 with benign prostatic hyperplasia (BPH). All tissue samples were confirmed by histology. Plasma samples were available for 52 prostate patients. We investigated HPV DNA prevalence by PCR, and PCR positive samples were HPV type determined by sequencing. Prevalence of antibodies against twenty-seven HPV proteins from fourteen different HPV types was assessed in the plasma samples. The HPV DNA prevalence in the tissue samples was 14% (7/51) for prostate cancer samples and 27% (3/11) for BPHs. HPV-18 was the only type detected in tissue samples (10/62). No significant difference in HPV prevalence between the prostate cancer and BPH samples was found. HPV-positive cells were identified in eight of our thirteen prostate tissue slides (3/3 BPH and 5/10 adenocarcinoma) by in situ hybridisation, and the positive cells were found in epithelial cells and peripheral blood cells. Serology data showed no significant increase in levels of antibodies against any of the HPV-18 proteins tested for in prostatic disease patients. Antibodies against HPV-1, HPV-4, HPV-6 and HPV-11 were significantly higher in the group of males with prostatic disease. Our study did not show an association between prostatic disease and either presence of HPV DNA in samples or previous exposure of high-risk HPV.