Personalised interventions for subgroups of children with conduct problems.

BACKGROUND: Conduct problems are a range of disruptive behaviours in childhood that are associated with long-term adverse outcomes in adolescence and adulthood, including antisocial behaviour, substance misuse, and poor academic achievement. Children with conduct problems can vary according to age of onset, comorbidities, and environmental factors, and it has been suggested that certain groups of children may have different treatment outcomes. Therefore, it is important to assess the extent to which personalised interventions for different groups of children with conduct problems may affect outcomes. To our knowledge, this is the first review to systematically identify and appraise the effectiveness of personalised interventions, adapted, or developed, for prespecified subgroups of children with conduct problems. OBJECTIVES: To assess whether personalised interventions, adapted or developed for subgroups of children with conduct problems are effective in improving outcomes. SEARCH METHODS: We used standard, extensive Cochrane search methods. The latest search was 1 February 2022. SELECTION CRITERIA: We included randomised controlled trials (RCTs), in any setting, in children (aged two to 12 years) with conduct problems and within a prespecified subgroup, comparing a personalised intervention with a non-personalised intervention, waitlist control, or treatment as usual. Personalised interventions included adaptations to standard practice, such as parent-training programmes; other recommended interventions for children with conduct problems; or interventions developed specifically to target subgroups of children with conduct problems. We excluded non-personalised and non-psychological interventions (e.g. pharmacological or dietary intervention). Prespecified subgroups of children with conduct problems, however defined, were eligible for inclusion. DATA COLLECTION AND ANALYSIS: We used standard Cochrane methods. Our primary outcomes were 1. child conduct problems or disruptive behaviour and 2. ADVERSE EVENTS: Our secondary outcomes were 3. personalised treatment outcomes relevant to each subgroup, 4. parenting skills and knowledge, 5. family functioning, engagement and decreased dropout, and 6. educational outcomes. We used GRADE to assess the certainty of the evidence. MAIN RESULTS: We identified 13 RCTs (858 participants). Seven studies were conducted in the USA, five in Australia, and one in Germany. Eleven studies reported their source of funding, with five studies receiving grants from the National Institute of Mental Health. In total, 15 different funders supported the studies included in the review. We separated subgroups of children with conduct problems into three broad categories: children with co-occurring conditions (e.g. emotional difficulties), parent characteristics (e.g. conflict between parents), or familial/environmental circumstances (e.g. rural families). All studies delivered a personalised intervention that was adapted or developed for a prespecified subgroup of children with conduct problems. We rated all trials at unclear or high risk of bias in most domains. Below, we report the results of improvement in child conduct problems and disruptive behaviour, personalised treatment outcomes, and parenting skills and knowledge for our main comparison: personalised versus non-personalised interventions. Improvement in child conduct problems and disruptive behaviour Compared with a non-personalised intervention, a personalised intervention may result in a slight improvement in child conduct problems or disruptive behaviour measured using the Eyberg Child Behavior Inventory (ECBI) Problem subscale in the short term (mean difference (MD) -3.04, 95% confidence interval (CI) -6.06 to -0.02; 6 studies, 278 participants; P = 0.05), but may have little to no effect on improving child conduct problems or disruptive behaviour measured by the ECBI Intensity subscale (MD -6.25, 95% CI -16.66 to 4.15; 6 studies, 278 participants; P = 0.24), or the Externalising subscale of the Child Behaviour Checklist (CBCL) (MD -2.19, 95% CI -6.97 to 2.59; 3 studies, 189 participants, P = 0.37) in the short term. We graded the certainty of evidence as very low for all three outcomes, meaning any estimate of effect is very uncertain.  Personalised treatment outcomes, relevant to each subgroup Although six studies reported personalised treatment outcomes, relevant to each subgroup, we were unable to pool the data due to differences between the measures used in the studies and the heterogeneity this would produce in analysis. The results for this outcome were inconclusive. Parenting skills and knowledge Although seven studies reported parenting skills and knowledge, we were unable to pool the data due to differences between the measures used in the studies and the heterogeneity this would produce in analysis. The results for this outcome were inconclusive.  Adverse events None of the trials reported monitoring adverse events. Summary of results In summary, there is limited evidence that personalised intervention improves child conduct problems, personalised treatment outcomes, relevant to each subgroup, or parenting skills and knowledge compared with a non-personalised intervention. AUTHORS' CONCLUSIONS: There is limited evidence for the effectiveness of personalised interventions for subgroups of children with conduct problems. The certainty of evidence for all outcomes was very low, meaning that we have very little confidence in the estimated effects and the true effects may be different to our findings, which will limit the relevance of our findings to clinical decisions. To overcome the limitations of the evidence, large-scale RCTs are needed to determine whether personalised interventions, adapted or developed, for subgroups of children with conduct problems are effective in improving outcomes. Consensus on the most appropriate measures to use in these studies is needed in order to facilitate cross-study comparisons. Persistent conduct problems predict a range of adverse long-term outcomes, so future research should investigate the medium- and long-term effects of personalised treatments. Studies are needed in low- and middle-income countries as well as studies recruiting children aged between nine and 12 years, as they were under-represented in the studies.

Primary Sclerosing Cholangitis and Psychological Wellbeing: A Scoping Review.

Primary sclerosing cholangitis (PSC) is a chronic liver disease resulting from the inflammation and scarring of an individual's hepatic bile ducts. With no curative treatment available and a risk of potentially severe complications and death, it is likely that those diagnosed with the illness may experience impairments in their psychological wellbeing. The aim of this scoping review is to locate, chart, and summarize all available literature on how PSC affects mental health and psychological wellbeing, as well as the factors that may or may not impact on the psychological wellbeing of those who have this diagnosis. This exercise identified five key themes within the literature: prevalence and characteristics of mental health problems, quality of life, unmet needs, medical treatment, and biomarkers. Three key recommendations for clinical practice emerge from this review.

Clinical characteristics associated with the prescribing of SSRI medication in adolescents with major unipolar depression.

Unipolar major depressions (MD) emerge markedly during adolescence. National Institute for Health and Care Excellence (NICE) UK recommends psychological therapies, with accompanying selective serotonin reuptake inhibitors (SSRIs) prescribed in severe cases only. Here, we seek to determine the extent and rationale of SSRI prescribing in adolescent MD before entering a randomised clinical trial. SSRI prescribing, together with their clinical characteristics was determined in 465 adolescent patients with MD prior to receiving a standardised psychological therapy as part of the Improving mood with psychoanalytic and cognitive therapies (IMPACT) clinical trial. Overall, 88 (19 %) had been prescribed antidepressants prior to psychological treatment. The clinical correlates varied by gender: respectively, depression severity in boys and self-harming behaviours in girls. Prescribing also differed between clinical research centres. Medical practitioners consider severity of depression in boys as an indicator for antidepressant prescribing. Self-injury in girls appears to be utilised as a prescribing aid which is inconsistent with past and current revised UK NICE guidelines.

Matrix metalloproteinase-9 activates TGF-ß and stimulates fibroblast contraction of collagen gels.

Matrix metalloproteinase-9 (MMP-9) is a matrix-degrading enzyme implicated in many biological processes, including inflammation. It is produced by many cells, including fibroblasts. When cultured in three-dimensional (3D) collagen gels, fibroblasts contract the surrounding matrix, a function that is thought to model the contraction that characterizes both normal wound repair and fibrosis. The current study was designed to evaluate the role of endogenously produced MMP-9 in fibroblast contraction of 3D collagen gels. Fibroblasts from mice lacking expression of MMP-9 and human lung fibroblasts (HFL-1) transfected with MMP-9 small-interfering RNA (siRNA) were used. Fibroblasts were cast into type I collagen gels and floated in culture medium with or without transforming growth factor (TGF)-ß1 for 5 days. Gel size was determined daily using an image analysis system. Gels made from MMP-9 siRNA-treated human fibroblasts contracted less than control fibroblasts, as did fibroblasts incubated with a nonspecific MMP inhibitor. Similarly, fibroblasts cultured from MMP-9-deficient mice contracted gels less than did fibroblasts from control mice. Transfection of the MMP-9-deficient murine fibroblasts with a vector expressing murine MMP-9 restored contractile activity to MMP-9-deficient fibroblasts. Inhibition of MMP-9 reduced active TGF-ß1 and reduced several TGF-ß1-driven responses, including activity of a Smad3 reporter gene and production of fibronectin. Because TGF-ß1 also drives fibroblast gel contraction, this suggests the mechanism for MMP-9 regulation of contraction is through the generation of active TGF-ß1. This study provides direct evidence that endogenously produced MMP-9 has a role in regulation of tissue contraction of 3D collagen gels mediated by fibroblasts.

The role of the lung microbiome in health and disease. A National Heart, Lung, and Blood Institute workshop report.

Study of the human lung microbiome in the context of pulmonary health and disease is an area of emerging research interest that is being driven by several contributing factors. These factors include increased recognition of the diversity of human-associated microbiota, their roles in health and in diseases associated with chronic inflammation, and advancements in technologies and tools that have facilitated such discoveries about the microbiota in organ systems outside of the lung. Therefore, the overarching goals of lung microbiome research are: to identify and characterize microbial populations associated with the respiratory tract and lungs; to understand their roles in lung health and disease; and, we hope, to allow the development of improved approaches for diagnosing and treating chronic respiratory diseases in which the microbiome has a role. Recent studies of the lung microbiome have yielded a number of interesting findings but also highlighted questions and challenges for researchers and clinicians. In December 2011, the National Heart, Lung, and Blood Institute convened a workshop to identify key issues and areas for further attention or development to advance research on the lung microbiome. Current knowledge and the state of research on the lung and related areas of human microbiome investigation were reviewed and discussed.

MMP9 induction by vascular endothelial growth factor receptor-1 is involved in lung-specific metastasis.

The molecular mechanism of tissue-specific metastasis in tumors endogenously expressing members of the vascular endothelial growth factor (VEGF) family is not yet clear. Here we demonstrate that MMP9 is specifically induced in premetastatic lung endothelial cells and macrophages by distant primary tumors via VEGFR-1/Flt-1 tyrosine kinase (TK) and that it significantly promotes lung metastasis. In a genetic approach using mice, suppression of MMP9 induction by deletion of either VEGFR-1TK or MMP9 markedly reduced lung metastasis. Furthermore, the MMP9 levels in endothelial cells of normal lung lobes from patients carrying distant tumors were significantly elevated as compared with those from patients without tumors. Thus, a block of MMP9 induction via VEGFR-1 inhibition could be useful for the prevention of tumor metastasis in lung.

The role of matrix metalloproteinase-9 in cigarette smoke-induced emphysema.

RATIONALE: Matrix metalloprotease (MMP)-9 is an elastolytic endopeptidase produced by activated macrophages that may be involved in the development of human pulmonary emphysema and could be inhibited with existing compounds. Mouse models have demonstrated that excess MMP-9 production can result in permanent alveolar destruction. OBJECTIVES: To determine if MMP-9 causes cigarette smoke-induced emphysema using MMP-9 knockout mice and human samples. METHODS: Mouse lungs were analyzed for inflammation and airspace enlargement using a mainstream smoke-exposure model. Human macrophage mRNA was isolated from subjects with emphysema by laser capture microdissection. Human blood monocyte mRNA was isolated from subjects with greater than 30 pack-year smoking history. Human gene expression was determined by quantitative polymerase chain reaction and compared with emphysema severity determined by automated computed tomography analysis. Plasma Clara cell secretory protein and surfactant protein-D were quantified to measure ongoing lung injury. MEASUREMENTS AND MAIN RESULTS: Mice deficient in MMP-9 develop the same degree of cigarette smoke-induced inflammation and airspace enlargement as strain-matched controls. Macrophages are the predominant source of MMP-9 production in human emphysema specimens and similar quantities of macrophage MMP-9 mRNA is present in areas of lung with and without emphysema. Circulating monocytes produce more MMP-9 in individuals with advanced emphysema severity despite no correlation of MMP-9 with markers of ongoing lung damage. CONCLUSIONS: These results suggest that MMP-9 in humans who smoke is similar to smoke-exposed mice, where MMP-9 is present in emphysematous lung but not correlated with the emphysema. To the degree that the mechanisms of emphysema in humans who smoke resemble the mouse model, these data suggest specific inhibition of MMP-9 is unlikely to be an effective therapy for cigarette smoke-induced emphysema. Clinical trial registered with www.clinicaltrials.gov (NCT 00757120).

In vivo detection of acinar microstructural changes in early emphysema with (3)He lung morphometry.

PURPOSE: To quantitatively characterize early emphysematous changes in the lung microstructure of current and former smokers with noninvasive helium 3 ((3)He) lung morphometry and to compare these results with the clinical standards, pulmonary function testing (PFT) and low-dose computed tomography (CT). MATERIALS AND METHODS: This study was approved by the local institutional review board, and all subjects provided informed consent. Thirty current and former smokers, each with a minimum 30-pack-year smoking history and mild or no abnormalities at PFT, underwent (3)He lung morphometry. This technique is based on diffusion MR imaging with hyperpolarized (3)He gas and yields quantitative localized in vivo measurements of acinar airway geometric parameters, such as airway radii, alveolar depth, and number of alveoli per unit lung volume. These measurements enable calculation of standard morphometric characteristics, such as mean linear intercept and surface-to-volume ratio. RESULTS: Noninvasive (3)He lung morphometry was used to detect alterations in acinar structure in smokers with normal PFT findings. When compared with smokers with the largest forced expiratory volume in 1 second (FEV(1)) to forced vital capacity (FVC) ratio, those with chronic obstructive pulmonary disease had significantly reduced alveolar depth (0.07 mm vs 0.13 mm) and enlarged acinar ducts (0.36 mm vs 0.3 mm). The mean alveolar geometry measurements in the healthiest subjects were in excellent quantitative agreement with literature values obtained by using invasive techniques (acinar duct radius, 0.3 mm; alveolar depth, 0.14 mm at 1 L above functional residual capacity). (3)He lung morphometry depicted greater abnormalities than did PFT and CT. No adverse events were associated with inhalation of (3)He gas. CONCLUSION: (3)He lung morphometry yields valuable noninvasive insight into early emphysematous changes in alveolar geometry with increased sensitivity compared with conventional techniques.

Maintenance of glomerular filtration barrier integrity requires laminin alpha5.

Mutation of the mouse laminin alpha5 gene results in a variety of developmental defects, including defects in kidney structure and function. Whereas the total absence of laminin alpha5 results in breakdown of the glomerular basement membrane (GBM) and failed glomerular vascularization, a hypomorphic Lama5 mutation (the Lama5(neo) allele) results in proteinuria, hematuria, polycystic kidney disease (PKD), and death 3 to 4 weeks after birth. Here, we examined the role of podocyte-derived laminin alpha5 via podocyte-specific inactivation of Lama5 and podocyte-specific rescue of the Lama5(neo) mutation. Podocyte-specific inactivation of Lama5 resulted in varying degrees of proteinuria and rates of progression to nephrotic syndrome. The GBM of proteinuric mice appeared thickened and "moth-eaten," and podocyte foot processes became effaced. Podocyte-specific restoration of laminin alpha5 production using two distinct strategies in Lama5(neo/neo) mice resulted in the resolution of proteinuria, hematuria, and PKD. These results suggest that the development of normal GBM structure and function requires podocyte-derived laminin alpha5 during and after glomerulogenesis and present a unique mechanism for the pathogenesis of PKD in these mice.

Longitudinal Outcomes of Gender Identity in Children (LOGIC): protocol for a prospective longitudinal cohort study of children referred to the UK gender identity development service.

INTRODUCTION: Gender identity development services (GIDS) worldwide have seen a significant increase in referrals in recent years. Many of these referrals consist of children and young people (CYP) who experience gender-related distress. This study aims to improve understanding of outcomes of CYP referred to the UK GIDS, specifically regarding gender identity, mental health, physical health and quality of life. The impact of factors such as co-occurring autism and early social transition on outcomes over time will be explored. METHODS AND ANALYSIS: This is a prospective cohort study of CYP aged 3-14 years when referred to the UK GIDS. Eligible participants will be ≤14 years at the time their referral was accepted and will be on the waitlist for the service when baseline measures are completed. Children aged under 12 years will complete the measures in an interview format with a researcher, while young people aged 12 years and over and their parents/caregivers will complete online or paper-based questionnaires. Participants will complete follow-up measures 12 months and 24 months later. The final sample size is expected to be approximately 500. Logistic regression models will be used to explore associations between prespecified explanatory variables and gender dysphoria. Appropriate regression models will also be used to investigate explanatory variables for other outcomes. Subgroup analyses based on birth-assigned gender, age at referral and co-occurring autistic traits will be explored. ETHICS AND DISSEMINATION: The study has been approved by the Health Research Authority and London - Hampstead Research Ethics Committee (reference: 19/LO/0857). The study findings will be published in peer-reviewed journals and presented at both conferences and stakeholder events. Findings will be used to inform clinical practice.

Longitudinal Outcomes of Gender Identity in Children (LOGIC): study protocol for a retrospective analysis of the characteristics and outcomes of children referred to specialist gender services in the UK and the Netherlands.

INTRODUCTION: Specialist gender services for children and young people (CYP) worldwide have experienced a significant increase in referrals in recent years. As rates of referrals increase, it is important to understand the characteristics and profile of CYP attending these services in order to inform treatment pathways and to ensure optimal outcomes. METHODS AND ANALYSIS: A retrospective observational study of clinical health records from specialist gender services for CYP in the UK and the Netherlands. The retrospective analysis will examine routinely collected clinical and outcome measures data including demographic, clinical, gender identity-related and healthcare resource use information. Data will be reported for each service and also compared between services. This study forms part of a wider programme of research investigating outcomes of gender identity in children (the Longitudinal Outcomes of Gender Identity in Children study). ETHICS AND DISSEMINATION: The proposed study has been approved by the Health Research Authority and London-Hampstead Research Ethics Committee as application 19/LO/0181. The study findings will be published in peer-reviewed journals and presented at both conferences and stakeholder events.

Ablation of matrix metalloproteinase-9 increases severity of viral myocarditis in mice.

BACKGROUND: Coxsackievirus B3 (CVB3) causes human myocarditis, which can result in cardiac damage, maladaptive remodeling, and heart failure. Matrix metalloproteinases (MMP)-8 and -9 have been identified in virus-infected myocardium, but their particular roles and underlying mechanisms of effect are unknown. For the first time, we examine the severity of CVB3-induced myocarditis in MMP-8-and MMP-9-deficient mice. METHODS AND RESULTS: CVB3-infected MMP-8 and MMP-9 knockout (KO) mice and corresponding wild-type (WT) mice were euthanized and harvested at 9 days after infection. Expression of MMP-2, -8, -12, and -13 and tissue inhibitors of MMPs was assessed by zymography or immunoblotting on harvested hearts, and in situ hybridization was performed to detect active infection. Infected MMP-9 KO mice had greater myocardial injury and foci of infection than WT mice despite similar pancreatic infection. Increased fibrosis (10.6+/-2.7% versus 7.1+/-2.6%, P=0.04), viral titer, as well as decreased cardiac output, were evident in MMP-9 KO compared with WT mice as assessed by picrosirius red staining, plaque assay, and echocardiography, respectively. Immune infiltration was also greatly increased in MMP-9 KO compared with WT mice (15.2+/-12.6% versus 2.0+/-3.0%, P<0.002). Myocardial interferon-beta1, interferon-gamma, interleukin-6, interleukin-10, and macrophage inflammatory protein-1alpha expression was elevated in MMP-9 KO mice as measured by quantitative real-time polymerase chain reaction and ELISA. In contrast, MMP-8 KO mice had the same degree of cardiac injury, fibrosis, and viral infection as their WT counterparts. CONCLUSIONS: During acute CVB3 infection, MMP-9 appears necessary to halt virus propagation in the heart, promote proper immune infiltration and remodeling, and preserve cardiac output.

Roles of a prostaglandin E-type receptor, EP3, in upregulation of matrix metalloproteinase-9 and vascular endothelial growth factor during enhancement of tumor metastasis.

Cyclooxygenase (COX)-2 is known to correlate with poor cancer prognosis and to contribute to tumor metastasis. However, the precise mechanism of this phenomenon remains unknown. We have previously reported that host stromal prostaglandin E(2) (PGE(2))-prostaglandin E2 receptor (EP)3 signaling appears critical for tumor-associated angiogenesis and tumor growth. Here we tested whether the EP3 receptor has a critical role in tumor metastasis. Lewis lung carcinoma (LLC) cells were intravenously injected into WT mice and mice treated with the COX-2 inhibitor NS-398. The nonselective COX inhibitor aspirin reduced lung metastasis, but the COX-1 inhibitor SC560 did not. The expression of matrix metalloproteinases (MMP)-9 and vascular endothelial growth factor (VEGF)-A was suppressed in NS-398-treated mice compared with PBS-treated mice. Lungs containing LLC colonies were markedly reduced in EP3 receptor knockout (EP3(-/-)) mice compared with WT mice. The expression of MMP-9 and VEGF-A was downregulated in metastatic lungs of EP3(-/-) mice. An immunohistochemical study revealed that MMP-9-expressing endothelial cells were markedly reduced in EP3(-/-) mice compared with WT mice. When HUVEC were treated with agonists for EP1, EP2, EP3, or EP4, only the EP3 agonist enhanced MMP-9 expression. These results suggested that EP3 receptor signaling on endothelial cells is essential for the MMP-9 upregulation that enhances tumor metastasis and angiogenesis. An EP3 receptor antagonist may be useful to protect against tumor metastasis.

Elastin fragments drive disease progression in a murine model of emphysema.

Mice lacking macrophage elastase (matrix metalloproteinase-12, or MMP-12) were previously shown to be protected from the development of cigarette smoke-induced emphysema and from the accumulation of lung macrophages normally induced by chronic exposure to cigarette smoke. To determine the basis for macrophage accumulation in experimental emphysema, we now show that bronchoalveolar lavage fluid from WT smoke-exposed animals contained chemotactic activity for monocytes in vitro that was absent in lavage fluid from macrophage elastase-deficient mice. Fractionation of the bronchoalveolar lavage fluid demonstrated the presence of elastin fragments only in the fractions containing chemotactic activity. An mAb against elastin fragments eliminated both the in vitro chemotactic activity and cigarette smoke-induced monocyte recruitment to the lung in vivo. Porcine pancreatic elastase was used to recruit monocytes to the lung and to generate emphysema. Elastin fragment antagonism in this model abrogated both macrophage accumulation and airspace enlargement.

Tumor necrosis factor-alpha from macrophages enhances LPS-induced clara cell expression of keratinocyte-derived chemokine.

Tumor necrosis factor (TNF)-alpha is a cytokine produced by alveolar macrophages in response to LPS in the lung. Clara cells are bronchiolar epithelial cells that produce a variety of proinflammatory cytokines in response to LPS but not to TNF-alpha. In this study, we examined whether TNF-alpha affects Clara cell cytokine production in the setting of LPS stimulation. Using a transformed murine Clara cell line (C22), we observed that both LPS and TNF-alpha induced production of keratinocyte-derived chemokine (KC) and monocyte chemoattractant protein (MCP)-1. We also found that simultaneous LPS and TNF-alpha stimulation is synergistic for KC production, but additive for MCP-1 production. By using a Transwell coculture system of RAW264.7 macrophages and Clara cells isolated from C57Bl/6 mice, we found that macrophages produce a soluble factor that enhances Clara cell KC production in response to LPS. Cocultures of Clara cells from mice deficient in TNF-alpha receptors with RAW264.7 macrophages demonstrated that the effect of macrophages on Clara cells is mediated primarily via TNF-alpha. To determine whether these findings occur in vivo, we treated wild-type and TNF receptor-deficient mice intratracheally with LPS and examined the expression of KC. LPS-treated, TNF receptor-deficient mice showed much less KC mRNA in airway epithelial cells compared with wild-type mice. In contrast, a similar number of KC-expressing cells was seen in the lung periphery. Thus, upregulation of KC by Clara cells in the setting of LPS stimulation is largely dependent on TNF-alpha originating from alveolar macrophages. These findings shed light on macrophage-Clara cell interactions in regulating the pulmonary inflammatory response to LPS.

Distal airways in mice exposed to cigarette smoke: Nrf2-regulated genes are increased in Clara cells.

Cigarette smoke (CS) is the main risk factor for chronic obstructive pulmonary disease (COPD). Terminal bronchioles are critical zones in the pathophysiology of COPD, but little is known about the cellular and molecular changes that occur in cells lining terminal bronchioles in response to CS. We subjected C57BL/6 mice to CS (6 d/wk, up to 6 mo), looked for morphologic changes lining the terminal bronchioles, and used laser capture microdissection to selectively isolate cells in terminal bronchioles to study gene expression. Morphologic and immunohistochemical analyses showed that Clara cell predominance remained despite 6 months of CS exposure. Since Clara cells have a role in protection against oxidative stress, we focused on the expression of antioxidant/detoxification genes using microarray analysis. Of the 35 antioxidant/detoxification genes with at least 2.5-fold increased expression in response to 6 months of CS exposure, 21 were NF-E2-related factor 2 (Nrf2)-regulated genes. Among these were cytochrome P450 1b1, glutathione reductase, thioredoxin reductase, and members of the glutathione S-transferase family, as well as Nrf2 itself. In vitro studies using immortalized murine Clara cells (C22) showed that CS induced the stabilization and nuclear translocation of Nrf2, which correlated with the induction of antioxidant and detoxification genes. Furthermore, decreasing Nrf2 expression by siRNA resulted in a corresponding decrease in CS-induced expression of several antioxidant and detoxification genes by C22 cells. These data suggest that the protective response by Clara cells to CS exposure is predominantly regulated by the transcription factor Nrf2.

Fragments of extracellular matrix as mediators of inflammation.

Classically, the extracellular matrix (ECM) was viewed as a supporting structure for stabilizing the location of cells in tissues and for preserving the architecture of tissues. This conception has changed dramatically over the past few decades with discoveries that ECM has profound influences on the structure, viability, and functions of cells. Much of the data supporting this new paradigm has been obtained from studies of normal and pathological structural cells such as fibroblasts, smooth muscle cells, and malignant cells, as, for example, breast cancer epithelial cells. However, there has also been recognition that effects of ECM on cells extend to inflammatory cells. In this context, attention has been drawn to fragments of ECM components. In this review, we present information supporting the concept that proteolytic fragments of ECM affect multiple functions and properties of inflammatory and immune cells. Our focus is particularly upon neutrophils, monocytes, and macrophages and fragments derived from collagens, elastin, and laminins. Hyaluronan fragments, although they are not products of proteolysis, are also discussed, as they are a notable example of ECM fragments that exhibit important effects on inflammatory cells. Further, we summarize some exciting recent developments in this field as a result of mouse models in which defined ECM fragments and their receptors are clearly implicated in inflammation in vivo. Thus, this review underscores the idea that proteolysis of ECM may well have implications that go beyond modifying the structural environment of cells and tissues.

Synergy between a plasminogen cascade and MMP-9 in autoimmune disease.

Extracellular proteolysis by the plasminogen/plasmin (Plg/plasmin) system and MMPs is required for tissue injury in autoimmune and inflammatory diseases. We demonstrate that a Plg cascade synergizes with MMP-9/gelatinase B in vivo during dermal-epidermal separation in an experimental model of bullous pemphigoid (BP), an autoimmune disease. BP was induced in mice by antibodies to the hemidesmosomal antigen BP180. Mice deficient in MMP-9 were resistant to experimental BP, while mice deficient in Plg and both tissue Plg activator (tPA) and urokinase Plg activator (uPA) showed delayed and less intense blister formation induced by antibodies to BP180. Plg-deficient mice reconstituted locally with Plg or the active form of MMP-9 (actMMP-9), but not the proenzyme form of MMP-9 (proMMP-9), developed BP. In contrast, proMMP-9 or actMMP-9, but not Plg, reconstituted susceptibility of MMP-9-deficient mice to the skin disease. In addition, MMP-3-deficient mice injected with pathogenic IgG developed the same degree of BP and expressed levels of actMMP-9 in the skin similar to those of WT controls. Thus, the Plg/plasmin system is epistatic to MMP-9 activation and subsequent dermal-epidermal separation in BP.

Clara cell adhesion and migration to extracellular matrix.

BACKGROUND: Clara cells are the epithelial progenitor cell of the small airways, a location known to be important in many lung disorders. Although migration of alveolar type II and bronchiolar ciliated epithelial cells has been examined, the migratory response of Clara cells has received little attention. METHODS: Using a modification of existing procedures for Clara cell isolation, we examined mouse Clara cells and a mouse Clara-like cell line (C22) for adhesion to and migration toward matrix substrate gradients, to establish the nature and integrin dependence of migration in Clara cells. RESULTS: We observed that Clara cells adhere preferentially to fibronectin (Fn) and type I collagen (Col I) similar to previous reports. Migration of Clara cells can be directed by a fixed gradient of matrix substrates (haptotaxis). Migration of the C22 cell line was similar to the Clara cells so integrin dependence of migration was evaluated with this cell line. As determined by competition with an RGD containing-peptide, migration of C22 cells toward Fn and laminin (Lm) 511 (formerly laminin 10) was significantly RGD integrin dependent, but migration toward Col I was RGD integrin independent, suggesting that Clara cells utilize different receptors for these different matrices. CONCLUSION: Thus, Clara cells resemble alveolar type II and bronchiolar ciliated epithelial cells by showing integrin mediated pro-migratory changes to extracellular matrix components that are present in tissues after injury.