Patient Reported Experiences and Delays During the Diagnostic Pathway for Pulmonary Fibrosis: A Multinational European Survey.

Introduction: Pulmonary fibrosis includes a spectrum of diseases and is incurable. There is a variation in disease course, but it is often progressive leading to increased breathlessness, impaired quality of life, and decreased life expectancy. Detection of pulmonary fibrosis is challenging, which contributes to considerable delays in diagnosis and treatment. More knowledge about the diagnostic journey from patients' perspective is needed to improve the diagnostic pathway. The aims of this study were to evaluate the time to diagnosis of pulmonary fibrosis, identify potential reasons for delays, and document patients emotions. Methods: Members of European patient organisations, with a self-reported diagnosis of pulmonary fibrosis, were invited to participate in an online survey. The survey assessed the diagnostic pathway retrospectively, focusing on four stages: (1) time from initial symptoms to first appointment in primary care; (2) time to hospital referral; (3) time to first hospital appointment; (4) time to final diagnosis. It comprised open-ended and closed questions focusing on time to diagnosis, factors contributing to delays, diagnostic tests, patient emotions, and information provision. Results: Two hundred and seventy three participants (214 idiopathic pulmonary fibrosis, 28 sarcoidosis, 31 other) from 13 countries responded. Forty percent of individuals took ≥1 year to receive a final diagnosis. Greatest delays were reported in stage 1, with only 50.2% making an appointment within 3 months. For stage 2, 73.3% reported a hospital referral within three primary care visits. However, 9.9% reported six or more visits. After referral, 76.9% of patients were assessed by a specialist within 3 months (stage 3) and 62.6% received a final diagnosis within 3 months of their first hospital visit (stage 4). Emotions during the journey were overall negative. A major need for more information and support during and after the diagnostic process was identified. Conclusion: The time to diagnose pulmonary fibrosis varies widely across Europe. Delays occur at each stage of the diagnostic pathway. Raising awareness about pulmonary fibrosis amongst the general population and healthcare workers is essential to shorten the time to diagnosis. Furthermore, there remains a need to provide patients with sufficient information and support at all stages of their diagnostic journey.

Coprocytobiology: A Technical Review of Cytological Colorectal Cancer Screening in Fecal Samples.

This review discusses the field of coprocytobiology, defined as a combined method of cell preservation, isolation, and cytology, which has applications to the investigation of noninvasive fecal screening for colorectal cancer. In the decade since the field was last reviewed, cell isolation has progressed rapidly via the development of technologies such as microfluidic and magnetic cell sorting. The landscape of cytology has also advanced in this time with the emergence of novel cytological methods and cell preservation strategies. Previous reviews present an outdated and incomplete view of coprocytobiology, summarizing a limited number of early publications, ignoring the principle of cell preservation and focusing on a single method of isolation rather than the field as a whole. In contrast to these publications, this review presents an updated, comprehensive, and unbiased representation of the technical aspects of coprocytobiology and provides unique insight into the common methodological pitfalls, best practice, and future directions of cytological screening for colorectal cancer.This review discusses the field of coprocytobiology, defined as a combined method of cell preservation, isolation, and cytology, which has applications to the investigation of noninvasive fecal screening for colorectal cancer. In the decade since the field was last reviewed, cell isolation has progressed rapidly via the development of technologies such as microfluidic and magnetic cell sorting. The landscape of cytology has also advanced in this time with the emergence of novel cytological methods and cell preservation strategies. Previous reviews present an outdated and incomplete view of coprocytobiology, summarizing a limited number of early publications, ignoring the principle of cell preservation and focusing on a single method of isolation rather than the field as a whole. In contrast to these publications, this review presents an updated, comprehensive, and unbiased representation of the technical aspects of coprocytobiology and provides unique insight into the common methodological pitfalls, best practice, and future directions of cytological screening for colorectal cancer.

Primary medication non-adherence to analgesics and antibiotics at Counties Manukau Health Emergency Department.

AIM: To measure primary medication non-adherence to antibiotics, paracetamol and nonsteroidal anti-inflammatory drugs (NSAIDs) in patients discharged from Counties Manukau Health Emergency Department (CMH-ED). METHOD: A retrospective observational study based on 1,600 discharged patients' data collected between 28 April-6 May and 28 July-9 August 2014. Data were included for patients who were residents within the Auckland Regional Public Health Service boundaries, presented to CMH-ED and were discharged with a prescription. RESULTS: Of 992 patients, 48.5% did not have at least one medication on their discharge prescription filled. Patients were mostly born in New Zealand (66.5%), of Pacific Island descent (42.8%), living in the most socioeconomically deprived areas (78.1%) and under 10 years of age (32.6%). Filling rates significantly increased with >1 prescribed item (p≤0.01). NSAIDs were significantly more likely to be filled compared with paracetamol (59.9% vs 51.3%, p=0.034); antibiotics were significantly more likely to be filled than all other medicines (80.4%, p<0.001). The most significant predictors for non-adherence when accounting for number and types of medications were patients 10-44 years (p<0.05) and smokers (p<0.01). CONCLUSIONS: Age, smoking and number of prescribed medications were predictors of non-adherence to medication type. Further research is warranted to assess whether changes to prescription co-payments affect the rate of nonadherence.

Rhinovirus-induced CCL17 and CCL22 in Asthma Exacerbations and Differential Regulation by STAT6.

The interplay of type-2 inflammation and antiviral immunity underpins asthma exacerbation pathogenesis. Virus infection induces type-2 inflammation-promoting chemokines CCL17 and CCL22 in asthma; however, mechanisms regulating induction are poorly understood. By using a human rhinovirus (RV) challenge model in human airway epithelial cells in vitro and mice in vivo, we assessed mechanisms regulating CCL17 and CCL22 expression. Subjects with mild to moderate asthma and healthy volunteers were experimentally infected with RV and airway CCL17 and CCL22 protein quantified. In vitro airway epithelial cell- and mouse-RV infection models were then used to define STAT6- and NF-κB-mediated regulation of CCL17 and CCL22 expression. Following RV infection, CCL17 and CCL22 expression was higher in asthma, which differentially correlated with clinical and immunological parameters. Air-liquid interface-differentiated primary epithelial cells from donors with asthma also expressed higher levels of RV-induced CCL22. RV infection boosted type-2 cytokine-induced STAT6 activation. In epithelial cells, type-2 cytokines and STAT6 activation had differential effects on chemokine expression, increasing CCL17 and suppressing CCL22, whereas NF-κB promoted expression of both chemokines. In mice, RV infection activated pulmonary STAT6, which was required for CCL17 but not CCL22 expression. STAT6-knockout mice infected with RV expressed increased levels of NF-κB-regulated chemokines, which was associated with rapid viral clearance. Therefore, RV-induced upregulation of CCL17 and CCL22 was mediated by NF-κB activation, whereas expression was differentially regulated by STAT6. Together, these findings suggest that therapeutic targeting of type-2 STAT6 activation alone will not block all inflammatory pathways during RV infection in asthma.

Primary medication non-adherence at Counties Manukau Health Emergency Department (CMH-ED), New Zealand: an observational study.

OBJECTIVES: To measure primary medication non-adherence (failure to fill prescription medicines) in patients discharged from the emergency department (ED), and to determine whether sociodemographic factors, smoking status and access to a general practitioner affect prescription filling. Little is known about primary medication non-adherence in EDs, and less so in New Zealand (NZ). Identifying reasons for non-adherence will enable development of strategies to improve adherence and reduce morbimortality. DESIGN AND SETTING: An observational study based on patient data from the ED of a large public hospital in South Auckland, NZ. PARTICIPANTS: Data were collected from 1600 patients discharged between 28 April-6 May and 28 July-9 August 2014. Data were included if patients were residents within the Auckland Regional Public Health Service boundaries, admitted to ED and discharged with a prescription. Data were excluded if patients were admitted to another ward, transferred to another hospital or left the ED without seeing a doctor. RESULTS: 992 patients were included in the study, the majority were under 10 years (32.6%), of Pacific Island descent (42.8%), NZ-born (67.7%) and living in the most socioeconomically deprived areas (78.1%). Almost 50% of patients failed to fill all prescription medications. Simple linear regression analysis indicated that non-adherence was significant for those 10-24 years (n=236; adherence=47.2%; p<0.05), of NZ Maori ethnicity (n=175; 51.3%; p=0.01), unemployed (n=77; 46.8%; p<0.01), homemakers (n=66; 45.7%; p<0.01), students (n=228; 55.6%; p<0.05) and cigarette smokers (n=139; 50.3%; p<0.01). Following multivariable analysis, the strongest predictors for non-adherence were those aged between 10 and 17 years (n=116; p<0.01), the unemployed (n=77; p=0.01) and homemakers (n=66; p=0.01). CONCLUSIONS: Age and occupation were the greater predictors of non-adherence; however, no other significant differences were found. Since this study, changes to prescription co-payments have been made. Further research is warranted to assess whether this change has more recently affected the rates of non-adherence.

Inhibition of mast cells: a novel mechanism by which nintedanib may elicit anti-fibrotic effects.

BACKGROUND: Idiopathic pulmonary fibrosis (IPF) is a chronic and progressive lung disease which presents a grave prognosis for diagnosed patients. Nintedanib (a triple tyrosine kinase inhibitor) and pirfenidone (unclear mechanism of action) are the only approved therapies for IPF, but have limited efficacy. The pathogenic mechanisms of this disease are not fully elucidated; however, a role for mast cells (MCs) has been postulated. OBJECTIVES: The aim of this work was to investigate a role for MCs in IPF and to understand whether nintedanib or pirfenidone could impact MC function. METHODS AND RESULTS: MCs were significantly elevated in human IPF lung and negatively correlated with baseline lung function (FVC). Importantly, MCs were positively associated with the number of fibroblast foci, which has been linked to increased mortality. Furthermore, MCs were increased in the region immediately surrounding the fibroblast foci, and co-culture studies confirmed a role for MC-fibroblast crosstalk in fibrosis. Nintedanib but not pirfenidone inhibited recombinant stem cell factor (SCF)-induced MC survival. Further evaluation of nintedanib determined that it also inhibited human fibroblast-mediated MC survival. This was likely via a direct effect on ckit (SCF receptor) since nintedanib blocked SCF-stimulated ckit phosphorylation, as well as downstream effects on MC proliferation and cytokine release. In addition, nintedanib ablated the increase in lung MCs and impacted high tissue density frequency (HDFm) in a rat bleomycin model of lung fibrosis. CONCLUSION: Nintedanib inhibits MC survival and activation and thus provides a novel additional mechanism by which this drug may exert anti-fibrotic effects in patients with IPF.

Distal lung epithelial progenitor cell function declines with age.

Tissue stem cell exhaustion is a key hallmark of aging, and in this study, we characterised its manifestation in the distal lung. We compared the lungs of 3- and 22-month old mice. We examined the gross morphological changes in these lungs, the density and function of epithelial progenitor populations and the epithelial gene expression profile. Bronchioles became smaller in their cross-sectional area and diameter. Using long-term EdU incorporation analysis and immunohistochemistry, we found that bronchiolar cell density remained stable with aging, but inferred rates of bronchiolar club progenitor cell self-renewal and differentiation were reduced, indicative of an overall slowdown in cellular turnover. Alveolar Type II progenitor cell density and self-renewal were maintained per unit tissue area with aging, but rates of inferred differentiation into Type I cells, and indeed overall density of Type I cells was reduced. Microarray analysis revealed age-related changes in multiple genes, including some with roles in proliferation and differentiation, and in IGF and TGFß signalling pathways. By characterising how lung stem cell dynamics change with aging, this study will elucidate how they contribute to age-related loss of pulmonary function, and pathogenesis of common age-related pulmonary diseases.

Healthcare Resource Utilization Among Patients in England with Systemic Sclerosis-Associated Interstitial Lung Disease: A Retrospective Database Analysis.

INTRODUCTION: Systemic sclerosis-associated interstitial lung disease (SSc-ILD) places a substantial burden on patients and healthcare systems. The objectives of this study were to describe clinical characteristics and assess healthcare resource utilization and costs of patients with SSc-ILD in England, compared with patients with non-pulmonary organ involvement related to SSc (SSc-OOI). METHODS: This population-based retrospective study used data from the Clinical Practice Research Datalink linked to Hospital Episode Statistics. Data were extracted from medical records dated January 1, 2005 to March 31, 2016. Patients with SSc were identified and placed in subgroups based on organ involvement: SSc-ILD, SSc-OOI, and both (SSc-ILD-OOI). Patients with SSc-ILD-OOI were included in both the SSc-ILD and SSc-OOI subgroups. All-cause healthcare costs, excluding medication costs, were calculated to 2016 British pounds sterling (£). RESULTS: This study included 675 patients with SSc: 174 (26%) had neither ILD nor other organ involvement (OOI); 127 (19%) had SSc-ILD; 477 (71%) had SSc-OOI; 103 (15%) had SSc-ILD-OOI. Age-weighted median [interquartile range (IQR)] annual healthcare costs per patient were: £1496 (£664-£2817) in SSc only; £6375 (£3451-£15,041) in SSc-ILD; £4084 (£1454-£10,105) in SSc-OOI; £6632 (£4023-£17,009) in SSc-ILD-OOI. In multivariate analysis, older age at diagnosis, diagnosis of anemia, and number of comorbid diseases were associated with higher yearly healthcare costs. CONCLUSION: The annual healthcare cost for patients with SSc-ILD is substantial, and higher than that of patients with SSc-OOI or SSc only. These results quantify the economic burden of SSc-ILD in a real-world setting, and highlight the need for treatment of this disease.

SSc is a rare disease that causes fibrosis, or thickening, of the skin. In some patients, SSc can also affect the lungs ('SSc-ILD') or other organs, e.g., the heart ('SSc-OOI'). Patients with SSc-ILD typically have high healthcare costs; however, it is not clear how costs for SSc-ILD compare with those for SSc-OOI. To investigate this, we evaluated the costs associated with SSc-ILD and compared them with those for SSc only or SSc-OOI. In this England-based study, the annual healthcare costs for patients with SSc-ILD were approximately 50% higher than for those without lung disease (SSc only) or SSc-OOI. These results highlight the importance of promptly diagnosing and treating patients with lung fibrosis complicating SSc.

Patients with paroxysmal nocturnal hemoglobinuria demonstrate a prothrombotic clotting phenotype which is improved by complement inhibition with eculizumab.

Paroxysmal nocturnal hemoglobinuria (PNH) is a rare hematological disorder, characterized by complement-mediated intravascular hemolysis and thrombosis. The increased incidence of PNH-driven thrombosis is still poorly understood, but unlike other thrombotic disorders, is thought to largely occur through complement-mediated mechanisms. Treatment with a C5 inhibitor, eculizumab, has been shown to significantly reduce the number of thromboembolic events in these patients. Based on previously described links between changes in fibrin clot structure and thrombosis in other disorders, our aim was to investigate clot structure as a possible mechanism of thrombosis in patients with PNH and the anti-thrombotic effects of eculizumab treatment on clot structure. Clot structure, fibrinogen levels and thrombin generation were examined in plasma samples from 82 patients from the National PNH Service in Leeds, UK. Untreated PNH patients were found to have increased levels of fibrinogen and thrombin generation, with subsequent prothrombotic changes in clot structure. No link was found between increasing disease severity and fibrinogen levels, thrombin generation, clot formation or structure. However, eculizumab treated patients showed decreased fibrinogen levels, thrombin generation and clot density, with increasing time spent on treatment augmenting these antithrombotic effects. These data suggest that PNH patients have a prothrombotic clot phenotype due to increased fibrinogen levels and thrombin generation, and that the antithrombotic effects of eculizumab are, in-part, due to reductions in fibrinogen and thrombin generation with downstream effects on clot structure.

Long intergenic non-coding RNAs regulate human lung fibroblast function: Implications for idiopathic pulmonary fibrosis.

Phenotypic changes in lung fibroblasts are believed to contribute to the development of Idiopathic Pulmonary Fibrosis (IPF), a progressive and fatal lung disease. Long intergenic non-coding RNAs (lincRNAs) have been identified as novel regulators of gene expression and protein activity. In non-stimulated cells, we observed reduced proliferation and inflammation but no difference in the fibrotic response of IPF fibroblasts. These functional changes in non-stimulated cells were associated with changes in the expression of the histone marks, H3K4me1, H3K4me3 and H3K27ac indicating a possible involvement of epigenetics. Following activation with TGF-ß1 and IL-1ß, we demonstrated an increased fibrotic but reduced inflammatory response in IPF fibroblasts. There was no significant difference in proliferation following PDGF exposure. The lincRNAs, LINC00960 and LINC01140 were upregulated in IPF fibroblasts. Knockdown studies showed that LINC00960 and LINC01140 were positive regulators of proliferation in both control and IPF fibroblasts but had no effect upon the fibrotic response. Knockdown of LINC01140 but not LINC00960 increased the inflammatory response, which was greater in IPF compared to control fibroblasts. Overall, these studies demonstrate for the first time that lincRNAs are important regulators of proliferation and inflammation in human lung fibroblasts and that these might mediate the reduced inflammatory response observed in IPF-derived fibroblasts.

Sleep characteristics, sources of perceived stress and coping strategies in adolescent athletes.

The aim of the study was to examine sleep characteristics, scheduling of activities, perceived stress and coping strategies between periods of perceived high and low scheduling commitments in adolescent athletes. Twenty adolescents (10 male and 10 female) wore an Actiwatch during two 14-day testing periods, one in in January (JAN), which was deemed to be a period of low school and sport commitments, and one in March (MAR), during which there was a high volume of school and sport commitments. Actiwatches and sleep diaries assessed sleep quantity and quality, a daily schedule of all activities in 30-min increments was recorded and questionnaires related to perceived stress and coping strategies were administered. Time in bed and asleep, latency, efficiency and number of awakenings were not different between JAN and MAR (p > 0.05). Sleep durations were lower than their age-related recommendations (JAN 449 ± 47 min versus MAR 437 ± 31 min). Examination of differences between sexes showed shorter latency and higher sleep efficiency in female participants compared with male participants. Participants spent more time at school, completing homework, and travelling to and competing in sport, with reduced time spent on resting, social activities, physical activity and meal times during MAR compared with JAN (p < 0.05). Finally, stress levels were significantly increased during MAR compared with JAN, with no difference between sexes (p < 0.05). Adolescent athletes not attaining sufficient sleep quantity or quality during periods of low and high school and sport commitments, are experiencing increased perceived stress during these busy times but are using a wider range of coping strategies during this time.

Long Non-coding RNAs Are Central Regulators of the IL-1ß-Induced Inflammatory Response in Normal and Idiopathic Pulmonary Lung Fibroblasts.

There is accumulating evidence to indicate that long non-coding RNAs (lncRNAs) are important regulators of the inflammatory response. In this report, we have employed next generation sequencing to identify 14 lncRNAs that are differentially expressed in human lung fibroblasts following the induction of inflammation using interleukin-1ß (IL-1ß). Knockdown of the two most highly expressed lncRNAs, IL7AS, and MIR3142HG, showed that IL7AS negatively regulated IL-6 release whilst MIR3142HG was a positive regulator of IL-8 and CCL2 release. Parallel studies in fibroblasts derived from patients with idiopathic pulmonary fibrosis showed similar increases in IL7AS levels, that also negatively regulate IL-6 release. In contrast, IL-1ß-induced MIR3142HG expression, and its metabolism to miR-146a, was reduced by 4- and 9-fold in IPF fibroblasts, respectively. This correlated with a reduced expression of inflammatory mediators whilst MIR3142HG knockdown showed no effect upon IL-8 and CCL2 release. Pharmacological studies showed that IL-1ß-induced IL7AS and MIR3142HG production and release of IL-6, IL-8, and CCL2 in both control and IPF fibroblasts were mediated via an NF-κB-mediated pathway. In summary, we have cataloged those lncRNAs that are differentially expressed following IL-1ß-activation of human lung fibroblasts, shown that IL7AS and MIR3142HG regulate the inflammatory response and demonstrated that the reduced inflammatory response in IPF fibroblast is correlated with attenuated expression of MIR3142HG/miR-146a.

Is personalised medicine the key to heterogeneity in idiopathic pulmonary fibrosis?

Idiopathic pulmonary fibrosis (IPF) is a chronic fibrosing interstitial pneumonia of unknown cause, characterised by progressive worsening in lung function and dyspnoea with an associated prognosis similar to or worse than many cancers. As a better understanding emerges around the pathogenesis and mechanisms driving disease pathology, a host of novel agents are being tested both pre-clinically and clinically. However even with this deeper understanding and positive pre-clinical supportive data, negative trial outcomes are frequently reported, highlighting the problems faced in treating such a heterogeneous disease with a varied clinical course. Recently, two therapies that slow disease progression, nintedanib and pirfenidone, have been approved for the treatment of IPF, yet the clinical unmet need is still high for IPF patients given their failure to stop disease progression and their potential side-effect profiles. Efforts are being made to not only understand the underlying pathways and genetics that might influence the clinical course of the disease, but also the non-invasive biomarkers that reflect the activity of specific pathways which in turn may highlight progressive treatment plans for individual patients. The cumulative data may be based on the identification of subgroups of patients via biomarker analysis of ongoing clinical trials, or investigation of cohorts of patients over time to understand the relative role of these mediators in their disease progression. Below we review the ongoing quest for novel therapeutic approaches and highlight, where appropriate attempts have been made to identify patients for which a specific pathway or mediator may be driving disease progression.

Patient awareness, knowledge and use of colchicine: an exploratory qualitative study in the Counties Manukau region, Auckland, New Zealand.

INTRODUCTION Treatment of gout, specifically with colchicine, varies globally. Colchicine can be fatal due to its narrow therapeutic index and potential for interactions. In New Zealand, cases of intentional and unintentional colchicine overdose have been documented. AIMS To explore patients' knowledge on the use of gout medicines, and in particular their awareness of the maximum dose of colchicine, the dangers of colchicine overdose, and their opinions on restricting colchicine dispensing. The study also investigates where patients receive gout information. METHODS Thirty people with gout presenting to their regular gout clinic in Auckland currently or previously taking colchicine were invited to participate in a 30-min semi-structured interview. Data were analysed using a general inductive thematic approach. FINDINGS Overall, participants had a lack of knowledge regarding colchicine and used variable doses during an acute gout attack. Participants were unsure of the maximum dose of colchicine and several took more than prescribed. The prophylactic use of colchicine and allopurinol varied from 3 weeks to 15 years. Mixed views were reported on restricting colchicine supply. Most participants received gout information from their general practitioner (GP). CONCLUSION Poor understanding of colchicine contributed to inappropriate use and highlights the need for targeted patient education. Considerable inter-patient variability exists in the use of colchicine for acute gout, suggesting the efficacy of low dose regimens be explored. The length of adjunctive colchicine use, as part of a prophylaxis regimen, needs to be regularly reviewed and tailored to each patient. Further research is required on limiting the amount of colchicine dispensed.

Effects of a classroom-based educational resource on adolescent mental health literacy: a cluster randomized controlled trial.

Evidence suggests that poor mental health literacy is a key barrier to help-seeking for mental health difficulties in adolescence. Educational programs have shown positive effects on literacy, however, the evidence base remains limited and available studies have many methodological limitations. Using cluster Randomised Control Trial (RCT) methodology, the current study examines the impact of 'HeadStrong', a school-based educational intervention, on mental health literacy, stigma, help-seeking, psychological distress and suicidal ideation. A total of 380 students in 22 classes (clusters) from 10 non-government secondary schools was randomised to receive either HeadStrong or Personal Development, Health and Physical Education (PDHPE) classes. Participants were assessed pre- and post-intervention, and at 6-month follow-up. Literacy improved and stigma reduced in both groups at post-intervention and follow-up, relative to baseline. However, these effects were significantly greater in the HeadStrong condition. The study demonstrates the potential of HeadStrong to improve mental health literacy and reduce stigma.

A crucial role for the ubiquitously expressed transcription factor Sp1 at early stages of hematopoietic specification.

Mammalian development is regulated by the interplay of tissue-specific and ubiquitously expressed transcription factors, such as Sp1. Sp1 knockout mice die in utero with multiple phenotypic aberrations, but the underlying molecular mechanism of this differentiation failure has been elusive. Here, we have used conditional knockout mice as well as the differentiation of mouse ES cells as a model with which to address this issue. To this end, we examined differentiation potential, global gene expression patterns and Sp1 target regions in Sp1 wild-type and Sp1-deficient cells representing different stages of hematopoiesis. Sp1(-/-) cells progress through most embryonic stages of blood cell development but cannot complete terminal differentiation. This failure to fully differentiate is not seen when Sp1 is knocked out at later developmental stages. For most Sp1 target and non-target genes, gene expression is unaffected by Sp1 inactivation. However, Cdx genes and multiple Hox genes are stage-specific targets of Sp1 and are downregulated at an early stage. As a consequence, expression of genes involved in hematopoietic specification is progressively deregulated. Our work demonstrates that the early absence of active Sp1 sets a cascade in motion that culminates in a failure of terminal hematopoietic differentiation and emphasizes the role of ubiquitously expressed transcription factors for tissue-specific gene regulation. In addition, our global side-by-side analysis of the response of the transcriptional network to perturbation sheds a new light on the regulatory hierarchy of hematopoietic specification.

The epithelium in idiopathic pulmonary fibrosis: breaking the barrier.

Idiopathic pulmonary fibrosis is a progressive disease of unknown etiology characterized by a dysregulated wound healing response that leads to fatal accumulation of fibroblasts and extracellular matrix (ECM) in the lung, which compromises tissue architecture and lung function capacity. Injury to type II alveolar epithelial cells is thought to be the key event for the initiation of the disease, and so far both genetic factors, such as mutations in telomerase and MUC5B genes as well as environmental components, like cigarette smoking, exposure to asbestos and viral infections have been implicated as potential initiating triggers. The injured epithelium then enters a state of senescence-associated secretory phenotype whereby it produces both pro-inflammatory and pro-fibrotic factors that contribute to the wound healing process in the lung. Immune cells, like macrophages and neutrophils as well as activated myofibroblasts then perpetuate this cascade of epithelial cell apoptosis and proliferation by release of pro-fibrotic transforming growth factor beta and continuous deposition of ECM stiffens the basement membrane, altogether having a deleterious impact on epithelial cell function. In this review, we describe the role of the epithelium as both a physical and immunological barrier between environment and self in the homeostatic versus diseased lung and explore the potential mechanisms of epithelial cell injury and the impact of loss of epithelial cell permeability and function on cytokine production, inflammation, and myofibroblast activation in the fibrotic lung.

Development of a mouse model mimicking key aspects of a viral asthma exacerbation.

Viral respiratory tract infections are known triggers of asthma exacerbations in both adults and children. The current standard of care, inhaled CS (corticosteroids) and LABAs (long-acting ß2-adrenoceptor agonists), fails to prevent the loss of control that manifests as an exacerbation. In order to better understand the mechanisms underlying viral asthma exacerbations we established an in vivo model using the clinically relevant aeroallergen HDM (house dust mite) and the viral mimetic/TLR3 (Toll-like receptor 3) agonist poly(I:C). Poly(I:C) alone induced a similar neutrophilic inflammatory profile in the BAL (bronchoalveolar lavage) to that of HRV1b (human rhinovirus 1b) alone, accompanied by both elevated BAL KC (keratinocyte-derived chemokine) and IL-1ß (interleukin-1ß). When mice allergic to HDM were also challenged with poly(I:C) the neutrophilic inflammatory profile was exacerbated. Increased CD8(+) T-cell numbers, increased CD4(+) and CD8(+) cell activation and elevated KC and IL-1ß were observed. No increases in Th2 cytokines or the eosinophil chemoattractant CCL11 [chemokine (C-C motif) ligand 11], above those induced by HDM alone, were observed. The poly(I:C)-exacerbated neutrophilia did not translate into changes in AHR (airways hyper-responsiveness), indicating that in this model inflammation and AHR are two mechanistically independent events. To test the clinical relevance of this model CS sensitivity was assessed using prednisone, a synthetic oral CS used to manage exacerbations in asthmatic patients already on maximal doses of inhaled CS. The increased neutrophils, and accompanying cytokines/chemokines KC and IL-1ß induced by poly(I:C) challenge of HDM-sensitized and challenged mice were insensitive to oral prednisone therapy. In summary we have described a CS-resistant mouse model mimicking the key aspects of viral asthma exacerbation using the clinically relevant aeroallergen HDM and the viral mimic poly(I:C). This model may provide better understanding of disease mechanisms underlying viral exacerbations and could be used to build early confidence in novel therapeutic axes targeting viral asthma exacerbations in Th2 asthmatics.

Matrix regulation of idiopathic pulmonary fibrosis: the role of enzymes.

Repairing damaged tissues is an essential homeostatic mechanism that enables clearance of dead or damaged cells after injury, and the maintenance of tissue integrity. However, exaggeration of this process in the lung can lead to the development of fibrotic scar tissue. This is characterized by excessive accumulation of extracellular matrix (ECM) components such as fibronectin, proteoglycans, hyaluronic acid, and interstitial collagens. After tissue injury, or a breakdown of tissue integrity, a cascade of events unfolds to maintain normal tissue homeostasis. Inflammatory mediators are released from injured epithelium, leading to both platelet activation and inflammatory cell migration. Inflammatory cells are capable of releasing multiple pro-inflammatory and fibrogenic mediators such as transforming growth factor (TGF)ß and interleukin (IL)-13, which can trigger myofibroblast proliferation and recruitment. The myofibroblast population is also expanded as a result of epithelial cells undergoing epithelial-to-mesenchymal transition and of the activation of resident fibroblasts, leading to ECM deposition and tissue remodeling. In the healthy lung, wound healing then proceeds to restore the normal architecture of the lung; however, fibrosis can develop when the wound is severe, the tissue injury persists, or the repair process becomes dysregulated. Understanding the processes regulating aberrant wound healing and the matrix in the chronic fibrotic lung disease idiopathic pulmonary fibrosis (IPF), is key to identifying new treatments for this chronic debilitating disease. This review focuses primarily on the emerging role of enzymes in the lungs of patients with IPF. Elevated expression of a number of enzymes that can directly modulate the ECM has been reported, and recent data indicates that modulating the activity of these enzymes can have a downstream effect on fibrotic tissue remodeling.