A case report of idiopathic pleuroparenchymal fibroelastosis with severe respiratory failure in pregnancy.

BACKGROUND: Idiopathic pleuroparenchymal fibroelastosis (IPPFE) is a rare lung disease that manifests as parenchymal fibrosis of the upper lung lobe and pleura. There have been no reports of IPPFE complicating pregnancy. Here, we report a case of IPPFE that deteriorated rapidly during pregnancy. CASE PRESENTATION: A 29-year-old woman presented with dyspnea and dry cough at 19 weeks of gestation. IPPFE with acute exacerbation was suspected on chest computed tomography (CT). Despite steroid treatment, her condition progressed. A cesarean section was performed at 28 weeks of gestation. On postoperative day 26, she underwent living-donor lung transplantation. She was discharged a year after transplantation. CONCLUSION: Our experience suggested that when pregnancy is complicated by PPFE, the disease may deteriorate rapidly. In this case, even though IPPFE with acute exacerbation was diagnosed during pregnancy, live birth was achieved, and the mother survived after lung transplantation. Lung transplantation should be considered in these patients because, once advanced, pulmonary lesions may be irreversible.

Transcription Elongation Factor P-TEFb Is Involved in IL-17F Signaling in Airway Smooth Muscle Cells.

BACKGROUND: IL-17F is involved in the pathogenesis of several inflammatory diseases, including asthma and COPD. However, the effects of steroids on the function of IL-17F signaling mechanisms are largely unknown. One of the transcription elongation factors, positive transcription elongation factor b (P-TEFb) composed of cyclin T1 and cyclin-dependent kinase 9 (CDK9), is known as a novel checkpoint regulator of gene expression via bromodomain-containing protein 4 (Brd4). METHODS: Human airway smooth muscle cells were stimulated with IL-17F and the expression of IL-8 was evaluated by real-time PCR and ELISA. Next, the phosphorylation of CDK9 was determined by Western blotting. The CDK9 inhibitor and short interfering RNAs (siRNAs) targeting Brd4, cyclin T1, and CDK9 were used to identify the effect on IL-17F-induced IL-8 expression. Finally, the effect of steroids and its signaling were evaluated. RESULTS: IL-17F markedly induced the transcription of the IL-8 gene and the expression of the protein. Pretreatment of CDK9 inhibitor and transfection of siRNAs targeting CDK9 markedly abrogated IL-17F-induced IL-8 production. Transfection of siRNAs targeting Brd4 and cyclin T1 diminished IL-17F-induced phosphorylation of CDK9 and IL-8 production. Moreover, budesonide decreased CDK9 phosphorylation and markedly inhibited IL-17F-induced IL-8 production. CONCLUSIONS: This is the first report that P-TEFb is involved in IL-17F-induced IL-8 expression and that steroids diminish it via the inhibition of CDK9 phosphorylation. IL-17F and P-TEFb might be novel therapeutic targets for airway inflammatory diseases.

[PROBLEMS ASSOCIATED WITH THE DIAGNOSIS OF PROLONGED/CHRONIC COUGH IN CLINICAL SETTINGS].

BACKGROUND: Many patients visit primary care clinics or local hospitals with a complaint of prolonged/chronic cough. Among the different types of chronic cough, cough variant asthma (CVA) and postinfectious cough may be the most common types, and their differential diagnosis is difficult. Some physicians tend to prescribe inhaled corticosteroids before establishing a definitive diagnosis. METHODS: We retrospectively investigated useful findings for diagnosis in 77 patients with a complaint of prolonged/ chronic cough to detect meaningful findings for differential diagnosis and to identify problems associated with diagnosis in clinical practice. RESULTS: CVA was diagnosed in 39 patients, and postinfectious cough was diagnosed in 19. Compared with postinfectious cough, CVA was associated with significant characteristics such as "diurnal variation of symptoms," "response to inhalation of short acting ß2 agonist (SABA)," and "recurrent episodes of symptoms." CVA was associated with high FeNO levels as well, and high FeNO levels were specific to CVA. However, these useful characteristics were not significant in the patients who had been prescribed ICS before visiting our hospital. CONCLUSIONS: Medical examination and determination of FeNO levels are useful for the differential diagnosis of prolonged/chronic cough, before treatment with ICS.

Overexpression of microRNA-155 suppresses chemokine expression induced by Interleukin-13 in BEAS-2B human bronchial epithelial cells.

BACKGROUND: MicroRNAs are non-coding small RNAs that regulate expression of target genes by binding to 3' untranslated regions. In this study, we used bronchial epithelial cells to investigate in vitro the role of the microRNA miR-155 in the expression of chemokines associated with airway inflammation. miR-155 has previously been reported to regulate allergic inflammation. METHODS: BEAS-2B bronchial epithelial cells were cultured and transfected with mimic or inhibitor oligonucleotides to overexpress or downregulate miR-155, as confirmed by real-time PCR. Cells were then stimulated with tumor necrosis factor-alpha, interleukin-13 (IL-13), and a double stranded RNA that binds Toll-like receptor 3. Expression and secretion of the chemokines CCL5, CCL11, CCL26, CXCL8, and CXCL10 were then quantified by real-time PCR and ELISA, respectively. Phosphorylation of signal transducer and activator of transcription 6 (STAT6), a target of the IL-13 receptor, was analyzed by ELISA. RESULTS: miR-155 overexpression significantly suppressed IL-13-induced secretion of CCL11 and CCL26. These effects were specific, and were not observed for other chemokines, nor in cells with downregulated miR-155. miR-155 overexpression also suppressed CCL11 and CCL26 mRNA, but did not affect expression of the IL-13 receptor or phosphorylation of STAT6. CONCLUSIONS: miR-155 specifically inhibits IL-13-induced expression of eosinophilic chemokines CCL11 and CCL26 in bronchial epithelial cells, even though the 3'-untranslated region of these genes do not contain a consensus binding site for miR-155.

Influence of Omalizumab on Allergen-Specific IgE in Patients with Adult Asthma.

BACKGROUND: Omalizumab, an anti-immunoglobulin E (IgE) monoclonal antibody, inhibits the binding of circulating IgE to mast cells and basophils, resulting in fewer episodes of airway inflammation, asthma symptoms and exacerbations in patients with severe allergic asthma. Treatment of patients with asthma using omalizumab increases serum total IgE (tIgE) levels. However, little is known about the influence of omalizumab on allergen-specific IgE (sIgE). METHODS: tIgE and sIgE in 47 adult patients with severe asthma were measured with a fluorescent enzyme immunoassay (ImmunoCAP-FEIA) before and after omalizumab treatment. RESULTS: Treatment with omalizumab increased tIgE and sIgE levels. The increases in sIgE by class category after omalizumab treatment were positively correlated with baseline sIgE positivity before treatment. The mean changes in sIgE levels after omalizumab treatment were also correlated with baseline sIgE levels before treatment. The mean changes in tIgE levels were positively correlated with the mean changes in IgE levels against Dermatophagoides pteronyssinus, crude house dust, Japanese cedar and moth. Omalizumab markedly influenced the negative-to-positive seroconversion rate for IgE against Japanese cedar (30.8%), Candida (29.0%) and moth (28.0%). Finally, all patients with negative-to-positive seroconversion for Japanese cedar-specific IgE had cedar pollinosis before beginning omalizumab treatment. CONCLUSIONS: The changes in sIgE levels after omalizumab treatment may be dependent on the baseline sIgE levels. Our data may indicate the presence of undetectable but functional sIgE.

Synthetic double-stranded RNA induces interleukin-32 in bronchial epithelial cells.

OBJECTIVE: Interleukin (IL)-32 is a novel cytokine and is involved in the pathogenesis of various inflammatory diseases, including asthma and COPD. However, the regulatory mechanisms of IL-32 expression and its precise pathogenic role remain to be defined. Given that viral infections are known to potentially cause and exacerbate airway inflammation, in this study, we investigated the expression of IL-32 induced by synthetic double-stranded (ds) RNA, and its signaling mechanisms involved. METHODS: Bronchial epithelial cells were stimulated with synthetic dsRNA poly I:C. The levels of IL-32 expression were analyzed using real-time PCR and ELISA. The involvement of transforming growth factor ß-activated kinase 1 (TAK1) and a subunit of nuclear factor-κB (NF-κB), p65 was determined by western blot analyses. TAK1 inhibitor, 5Z-7-Oxozeaenol and NF-κB inhibitor, BAY 11-7082 were added to the culture to identify key signaling events leading to the expression of IL-32. Finally, the effect of short interfering RNAs (siRNAs) targeting TAK1 and p65 was investigated. RESULTS: dsRNA significantly induced IL-32 gene and protein expression, concomitant with activation of TAK1 and p65. Pretreatment of 5Z-7-Oxozeaenol diminished dsRNA-induced phosphorylation of NF-κB. Both 5Z-7-Oxozeaenol and BAY 11-7082 significantly abrogated dsRNA-induced IL-32 production. Moreover, transfection of the cells with siRNAs targeting TAK1 and p65 inhibited the expression of IL-32. CONCLUSIONS: The expression of IL-32 is induced by dsRNA via the TAK1-NF-κB signaling pathway in bronchial epithelial cells. IL-32 is involved in the pathogenesis of airway inflammation, and may be a novel therapeutic target for airway inflammatory diseases.

Clinical features and outcomes of aspiration pneumonia compared with non-aspiration pneumonia: a retrospective cohort study.

Pneumonia is a leading cause of death among elderly patients. Although aspiration pneumonia (AP) commonly occurs with aging, its clinical features and outcomes are still uncertain. The aims of this study were to describe the clinical features and outcomes of AP and to assess whether presence of AP affects clinical outcomes in patients with community-acquired pneumonia (CAP) and healthcare-associated pneumonia (HCAP). We retrospectively analyzed patients with CAP and HCAP hospitalized in our institution in Japan from October 2010 to March 2012. We compared clinical features and outcomes between AP and non-AP, and investigated risk factors for recurrence of pneumonia and death. Of 214 consecutive patients, 100 (46.7%) were diagnosed as having aspiration pneumonia. These patients were older and had lower body mass index, more comorbidities, and poorer Eastern Cooperative Oncology Group performance status (ECOG PS) than the patients with non-AP. Patients with AP had more severe disease, required longer hospital stays, and had a frequent recurrence rate of pneumonia and higher mortality. In multivariate analyses, AP, age, and ECOG PS were related to recurrence of pneumonia, and the prognostic factors were CURB-65 score and ECOG PS. AP was not a significant indicator for prognosis but was the strongest risk factor for recurrence of pneumonia. Clinical background and outcomes including recurrence and mortality of AP were obviously different from those of non-AP; therefore AP should be considered as a distinct subtype of pneumonia, and it is important to prevent the recurrence of pneumonia in the patients with AP.

Time to diagnosis of nontuberculous mycobacterial pulmonary disease and longitudinal changes on CT before diagnosis.

Background: The healthcare burden of nontuberculous mycobacterial pulmonary disease (NTM-PD) is increasing, but the diagnosis remains challenging and sometimes requires considerable time. This nested case-control study aims to clarify the time to diagnosis of NTM-PD, the factors that affect diagnosis and diagnostic delay, and changes in CT findings before diagnosis. Patients and methods: We retrospectively analyzed 187 patients suspected of having NTM-PD based on computed tomography (CT) findings at our institution between January 2019 and September 2020. We investigated the time to diagnosis of NTM-PD for all suspected and diagnosed patients. Multivariate analyses identified the factors affecting diagnosis and diagnostic delay over 6 months. We also evaluated longitudinal changes in CT findings during the observation period using CT scoring system. Results: The median times to diagnosis of NTM-PD were 71.8 months in all suspected patients and 3.2 months in only the diagnosed patients. Multivariable analysis showed that severity of the cavity domain of the CT score and anti-glycopeptidolipid (GPL)-core immunoglobulin A (IgA) antibody positivity were significantly associated with establishing the diagnosis. A low CT score in the cavity domain was a risk factor for delayed diagnosis. In patients with delayed diagnosis, the total CT score was less severe than that in the early diagnosis patients at their first visits; however, it had deteriorated prior to the diagnosis. Conclusion: The diagnosis of NTM-PD sometimes required several years, and the absence or mild cavitation predicted a diagnostic delay. Of concern, a delay in diagnosis can result in a delay in treatment.

Interleukin-33-activated dendritic cells induce the production of thymus and activation-regulated chemokine and macrophage-derived chemokine.

BACKGROUND: Interleukin (IL)-33, a new member of the IL-1 cytokine family, is involved in T helper (Th)2-type responses in a wide range of diseases and is mediated by expression of the ST2 receptor in many immune cells. As the effects of IL-33 on dendritic cells (DCs) remain controversial, we investigated the ability of IL-33 to modulate the functions of these cells. METHODS: DCs were derived from mouse bone marrow, and the expression of the IL-33 receptor ST2 was examined by fluorescence-activated cell sorting and RT-PCR. The responses of the DCs to IL-33 were examined by RT-PCR and ELISA, and activation of mitogen-activated protein kinases (MAPKs) was determined by Western blotting. RESULTS: ST2 ligand mRNA and protein were detectable in DCs. IL-33 induced the production of thymus and activation-regulated chemokine/CCL17 and macrophage-derived chemokine/CCL22 and the activation of extracellular signal-regulated kinase 1/2, c-Jun N-terminal kinase and p38 MAPK. CONCLUSIONS: DCs respond directly to IL-33 through ST2. The interaction between IL-33 and DCs may represent a new pathway to initiate Th2-type immune responses. IL-33 and ST2 may play important roles in allergic inflammation.

Basic research on virus-induced asthma exacerbation: inhibition of inflammatory chemokine expression by fluticasone propionate.

BACKGROUND: Viral infection can exacerbate asthma by inducing the accumulation of inflammatory cells in the airway. We have previously reported that double-stranded RNA (dsRNA), a viral product and ligand of the Toll-like receptor-3 (TLR3), activates the transcription factors NF-κB and IRF-3 and upregulates the expression of inflammatory chemokines in airway epithelial cells. Here, we examined the effects of the glucocorticoid fluticasone propionate (FP) on the expression of the inflammatory chemokines CCL5, CXCL8 and CXCL10. METHODS: The airway epithelial cell line BEAS-2B was used for this study. Expression of CCL5, CXCL8 and CXCL10 mRNA and protein was quantified by real-time PCR and ELISA assay, respectively. To examine the association of FP with the physiology of chemokine production, we included several methods. Nuclear translocation of transcription factors was determined by performing Western blot analysis. Histone deacetylase (HDAC) activity in nuclear extracts was measured using a colorimetric assay. Stability of the chemokine mRNAs was examined in cells incubated with actinomycin D. The activities of the CCL5 promoter and the transcription factors NF-κB and IRF-3 were assessed using luciferase reporter assays. RESULTS: Treatment of BEAS-2B cells with FP significantly and dose-dependently (10(-9) to 10(-6)M) inhibited dsRNA-induced expression of CCL5, CXCL8 and CXCL10 protein and mRNA, but did not affect mRNA stability. FP also significantly inhibited dsRNA-stimulated CCL5 promoter activity. However, FP had no effect on the activity of HDAC or the nuclear translocation of NF-κB and IRF-3. CONCLUSIONS: FP inhibits the dsRNA-stimulated expression of inflammatory chemokines in airway epithelial cells. FP may act by inhibiting chemokine transcription through an as yet unidentified mechanism.

Eosinophilic gastroenteritis due to cow's milk allergy presenting with acute pancreatitis.

Eosinophilic gastroenteritis (EGE) is characterized by eosinophilic infiltration of the digestive organs, most commonly of the stomach and the duodenum. Symptoms of EGE are nonspecific and include nausea, vomiting, abdominal pain, dyspepsia, malabsorption, ascites and weight loss. The various symptoms of EGE depend on its location and the depth of gastrointestinal eosinophil infiltration. We report a case presenting with acute pancreatitis caused by a milk allergy. The patient's symptoms rapidly improved after treatment with corticosteroids, and he remained symptom-free for more than 20 months by the elimination of cow's milk from his diet. Serum titers of pancreatic enzymes and total bilirubin simultaneously recovered and blood eosinophil counts normalized. The causative allergens of EGE are too various to detect; however, allergologic exams revealed that a cow's milk allergy had provoked EGE in our case. Adult-onset cow's milk allergies are rare; when seen, however, they may present severe complications such as anaphylaxis, gastroenteritis and pancreatitis. When unaccountable gastrointestinal symptoms are observed, EGE caused by food allergies should be included in the differential diagnosis.

[A case of severe asthma and peach allergy that improved with omalizumab therapy: a case report].

A 30-year-old woman had refractory asthma. She had also experienced twice severe anaphylaxis episodes after ingesting peaches. The patient was extremely wary about reoccurrence of anaphylaxis and avoided ingesting any fruits, including peaches. She visited our hospital for testing and treatment for asthma and the peach allergy. Skin and serologic testing showed that she had a severe allergy to house dust, mites, and peaches. The food challenge test results showed that ingesting 6.5 g of the peach fruit induced dyspnea in the patient. Her asthma could not be controlled despite treatment involving a leukotriene receptor antagonist and combination inhalation of high-dose salmeterol xinafoate/fluticasone propionate. We advised the patient to keep strict avoidance ingesting peaches because of her food allergy. However, she hoped to overcome her food restrictions, especially those for fruits. We initiated treatment involving the recombinant humanized monoclonal anti-IgE antibody omalizumab (150 mg, once a month) to ensure that the asthma was controlled well and to improve the patient's diet. The asthmatic symptoms ameliorated, and the peak expiratory flow increased in a short time. We gradually reduced the restriction on peach consumption. This was achieved by rechallenging the patient with increasing doses of 290 mg of the peach fruit and was initiated at 28 weeks after starting omalizumab therapy. The restriction on peach consumption was lifted eventually, and the patient did not experience any allergic symptoms subsequently on ingesting peaches. Thus, for our patient, omalizumab therapy was highly effective in achieving remission from both asthma and peach allergy.

Expression and effects of IL-33 and ST2 in allergic bronchial asthma: IL-33 induces eotaxin production in lung fibroblasts.

BACKGROUND: Interleukin (IL)-33, a new member of the IL-1 cytokine family, has been recognized as a key cytokine that enhances T helper 2-balanced immune regulation through its receptor ST2; however, the function and relationship of the IL-33 and ST2 pathways in bronchial asthma are still unclear. We investigated the cellular origin and regulation of IL-33 and ST2 in allergic bronchial asthma in vivo and in vitro. METHODS: BALB/c mice were sensitized by intraperitoneal injections of ovalbumin (OVA) with alum. Mice were exposed to aerosolized 1% OVA for 30 min a day for 7 days. These mice were then challenged with aerosolized 1% OVA 2 days after the last day of exposure. After the OVA challenge, the mice were sacrificed and their lung tissues were obtained. Mouse lung fibroblasts were cultured and treated with IL-33 or IL-13. RESULTS: The levels of IL-33 mRNA and IL-33 protein in lung tissue increased after the OVA challenge. Most IL-33-expressing cells were CD11c+ cells and epithelial cells, and many ST2-expressing cells were stained lung fibroblasts and inflammatory cells. IL-33 induced eotaxin/CCL11 production in lung fibroblasts. IL-33 and IL-13 synergistically induced eotaxin expression. CONCLUSIONS: IL-33 may contribute to the induction and maintenance of eosinophilic inflammation in the airways by acting on lung fibroblasts. IL-33 and ST2 may play important roles in allergic bronchial asthma.

Oxaliplatin-induced lung injury with allergic reaction.

A 79-year-old man was diagnosed as stage IV colon cancer and treated with a modified FOLFOX6 (mFOLFOX6) regimen. On the 12th cycle, we observed erythema and dyspnea. Radiographs showed ground grass opacities. Blood tests showed elevated levels of eosinophils and immunoglobulin E. We diagnosed this finding as response to drug allergy and administered high-dose methylprednisolone. The treatment was successful and he was discharged. The drug lymphocyte stimulating test against oxaliplatin was positive, indicating a type I and IV allergic reaction due to oxaliplatin. Regimens including oxaliplatin must be carefully monitored and frequent blood tests and chest radiographs are needed.

Regulatory role of DC-derived osteopontin in systemic allergen sensitization.

Osteopontin (OPN) is a secreted phosphoglycoprotein with a wide range of functions, and is involved in various pathophysiological conditions. However, the role of OPN in IgE and Th2-associated allergic responses remains incompletely defined. The aim of this study was to elucidate the role of OPN in systemic allergen sensitization in mice. When compared with OPN(+/+) mice, significantly increased levels of OVA-induced IgE were found in OPN(-/-) mice. OPN(-/-) DC demonstrated an increased capacity to enhance Th2 cytokine production in CD4+ T cells from sensitized OPN(+/+) mice. Furthermore, significantly reduced levels of IL-12p70 expression were seen in LPS-stimulated OPN(-/-) DC as compared with the WT DC, and the reduction was reversible by the addition of recombinant OPN (rOPN). rOPN was able to suppress OVA-induced IL-13 production in the cultures of CD4 and OPN(-/-) DC, but this inhibitory activity was neutralized by the addition of anti-IL-12 Ab. In addition, administration of rOPN in vivo suppressed OVA-specific IgE production; however, this suppressive effect was abrogated in IL-12-deficient mice. These results indicate that DC-derived OPN plays a regulatory role in the development of systemic allergen sensitization, which is mediated, at least in part, through the production of endogenous IL-12.

Cooperative activation of CCL5 expression by TLR3 and tumor necrosis factor-alpha or interferon-gamma through nuclear factor-kappaB or STAT-1 in airway epithelial cells.

BACKGROUND: CCL5/RANTES contributes to prolonged eosinophilic inflammation and asthma exacerbation after a viral infection. We studied the mechanism of CCL5 expression using viral product double-stranded RNA (dsRNA), a ligand of Toll-like receptor 3 (TLR3), and inflammatory cytokines in airway epithelial cells. METHODS: The airway epithelial cell line BEAS-2B was used in our in vitro study, and the levels of CCL5 mRNA and CCL5 protein expression were determined using real-time PCR and ELISA. The activity of the CCL5 promoter region and nuclear factor (NF)-kappaB was assessed by dual luciferase assay using specific luciferase reporter plasmids. We used actinomycin D to assess the stability of mRNA. Phosphorylation of signal transducer and activator of transcription 1 (STAT-1) was analyzed by Western blot. RESULTS: Synthetic dsRNA up-regulated the expression of CCL5 mRNA and CCL5 protein. Adding TNF-alpha or IFN-gamma to dsRNA further increased the expression of CCL5. The combination of TNF-alpha and dsRNA cooperatively activated the CCL5 promoter region and the NF-kappaB-specific reporter. IFN-gamma did not activate these reporters. However, it increased the stability of CCL5 mRNA induced by dsRNA. IFN-gamma phosphorylated STAT-1, but dsRNA did not. The effects of IFN-gamma were not evident in the cells transfected with short interfering RNA for STAT-1. CONCLUSIONS: Cross-talk between TLR3 signaling and inflammatory cytokines regulates the expression of CCL5 in airway epithelial cells. In this mechanism, TNF-alpha may activate NF-kappaB, in cooperation with TLR3 signaling. IFN-gamma may stabilize CCL5 mRNA up-regulated by TLR3. This mechanism may depend on STAT-1.

Effects of corticosteroids on osteopontin expression in a murine model of allergic asthma.

BACKGROUND: Osteopontin (OPN) contributes to the development of T helper 1 (Th1)-mediated immunity and Th1-associated diseases. However, the role of OPN in bronchial asthma is unclear. Corticosteroids reduce airway inflammation, as reflected by the low eosinophil and T-cell counts, and the low level of cytokine expression. We investigated OPN production and the inhibitory effects of corticosteroids on OPN production in a murine model of allergic asthma. METHODS: BALB/c mice were sensitized by intraperitoneal injections of ovalbumin (OVA) with alum. Some mice received daily injections of dexamethasone (DEX) or phosphate-buffered saline for 1 week. All OVA-challenged mice were exposed to aerosolized 1% OVA for 30 min an hour after these injections. After the OVA challenge, the mice were killed, and bronchoalveolar lavage (BAL) fluid and lung tissue were examined. RESULTS: The levels of OPN protein in BAL fluid and OPN mRNA in lung tissue increased after OVA challenge. Most OPN-expressing cells were CD11c+ cells and some were T cells. DEX decreased the levels of OPN protein in the BAL fluid, and those of OPN mRNA and OPN protein in lung tissue. CONCLUSIONS: OPN may play an important role in allergic bronchial asthma. Corticosteroids inhibit OPN production in mice with allergic asthma. The beneficial effect of corticosteroids in bronchial asthma is partly due to their inhibitory effects on OPN production.

Differential regulation of eotaxin expression by dexamethasone in normal human lung fibroblasts.

Lung fibroblasts are a major source of several cytokines including CC chemokine eotaxin. We aimed to study the regulation of eotaxin-1/CCL11 production by dexamethasone and analyze its molecular mechanisms in human lung fibroblasts. Normal human lung fibroblast cells were exposed to IL-4 (40 ng/ml) and/or dexamethasone (10(-6)-10(-9) M), and eotaxin mRNA expression and production was evaluated. Mechanisms of transcriptional regulation were assessed by Western blotting and dual luciferase assay for eotaxin promoter. The effects of dexamethasone on suppressor of cytokine signaling (SOCS)-1 and eotaxin mRNA expression in the cells transfected with expression vector (pAcGFP1-C1) or short interfering RNA (siRNA) for SOCS-1 were also investigated. Within 24 hours, dexamethasone inhibited IL-4-induced eotaxin mRNA expression and protein production, while eotaxin production was markedly increased at 48 and 72 hours after coincubation with IL-4 and dexamethasone. IL-4-induced eotaxin promoter activity was inhibited by dexamethasone at 8 hours, but enhanced at 48 hours after coincubation. Dexamethasone suppressed SOCS-1 mRNA expression but enhanced IL-4-induced STAT6 phosphorylation at 36 to 48 hours after coincubation. Enhanced expression of eotaxin mRNA by dexamethasone 48 hours after coincubation was completely diminished in the cells transfected with either expression vector or siRNA for SOCS-1. These results indicated that dexamethasone, depending on the exposure duration, can either inhibit or enhance IL-4-induced expression and production of eotaxin in the lung fibroblasts. The mechanisms of later enhanced production may depend on the prolonged transcriptional activity of the eotaxin gene, in part due to inhibition of SOCS-1 expression.

Increase in reactive oxygen metabolite level in acute exacerbations of asthma.

BACKGROUND: Oxidants including reactive oxygen species have been indicated to play an important role in the pathogenesis of asthma. OBJECTIVE: We investigated oxidative status in patients with acute exacerbations of asthma and evaluated the therapeutic response using the D-ROM test which is simple to use and quick. METHODS: We measured reactive oxygen metabolite (ROM) levels in the serum of 42 outpatients with acute exacerbations of asthma, 11 outpatients with stable asthma and 40 healthy subjects using the D-ROM test. Seven inpatients admitted due to acute exacerbations of asthma were also enrolled to evaluate the effects of treatment. Serum eosinophil cationic protein and plasma polymorphonuclear elastase were also measured by EIA or ELISA to evaluate the correlation between inflammation and oxidative status. RESULTS: Serum ROM levels were significantly higher in patients with acute exacerbation of asthma than in patients with stable asthma or healthy subjects. Levels of serum eosinophil cationic protein and plasma polymorphonuclear elastase were increased in acute exacerbation and moderately correlated to ROM levels. Levels of ROM were significantly decreased after treatment with systemic steroids and bronchodilators. CONCLUSION: These findings suggest that acute exacerbation of asthma is associated with increased oxidative stress. Serum ROM levels would partly reflect the inflammation with eosinophils and neutrophils and may be useful as biomarkers of asthma.