Induction of mucin and MUC5AC expression by the protease activity of Aspergillus fumigatus in airway epithelial cells.

Allergic bronchopulmonary mycosis, characterized by excessive mucus secretion, airflow limitation, bronchiectasis, and peripheral blood eosinophilia, is predominantly caused by a fungal pathogen, Aspergillus fumigatus. Using DNA microarray analysis of NCI-H292 cells, a human bronchial epithelial cell line, stimulated with fungal extracts from A. fumigatus, Alternaria alternata, or Penicillium notatum, we identified a mucin-related MUC5AC as one of the genes, the expression of which was selectively induced by A. fumigatus. Quantitative RT-PCR, ELISA, and histochemical analyses confirmed an induction of mucin and MUC5AC expression by A. fumigatus extracts or the culture supernatant of live microorganisms in NCI-H292 cells and primary cultures of airway epithelial cells. The expression of MUC5AC induced by A. fumigatus extracts diminished in the presence of neutralizing Abs or of inhibitors of the epidermal growth factor receptor or its ligand, TGF-α. We also found that A. fumigatus extracts activated the TNF-α-converting enzyme (TACE), critical for the cleavage of membrane-bound pro-TGF-α, and its inhibition with low-molecular weight inhibitors or small interfering RNA suppressed the expression of MUC5AC. The protease activity of A. fumigatus extracts was greater than that of other fungal extracts, and treatment with a serine protease inhibitor, but not with a cysteine protease inhibitor, eliminated its ability to activate TACE or induce the expression of MUC5AC mRNA in NCI-H292. In conclusion, the prominent serine protease activity of A. fumigatus, which caused the overproduction of mucus by the bronchial epithelium via the activation of the TACE/TGF-α/epidermal growth factor receptor pathway, may be a pathogenetic mechanism of allergic bronchopulmonary mycosis.

Prediction of requirement for mechanical ventilation in community-acquired pneumonia with acute respiratory failure: a multicenter prospective study.

BACKGROUND: Several severity scoring systems for predicting mortality are established in community-acquired pneumonia (CAP). OBJECTIVES: The predictability of the aggravation such as requirement for mechanical ventilation in addition to mortality was examined in CAP patients with acute respiratory failure by using the age, dehydration, respiratory failure, orientation disturbance and blood pressure (A-DROP) scoring system which was proposed by the Japanese Respiratory Society. METHODS: This study was a prospective, multicenter, observational cohort study. The severity of pneumonia was examined using A-DROP and Pneumonia Severity Index (PSI) which originated from the Infectious Disease Society of America. Requirement for mechanical ventilation and mortality were evaluated for 28 days. RESULTS: 482 CAP patients with acute respiratory failure were enrolled in the study. The 28-day mortality and mechanical ventilation rates were 12.3 and 14.4%, respectively. There were no significant differences in the areas under the receiver-operator characteristic curves for prediction of mortality between A-DROP and PSI (χ² test; p = 0.3613). In the subgroup analyses by severity, the A-DROP scoring system showed a severity-dependent increase of mortality (moderate 5.6%, severe 16.1%, extremely severe 27.1%, Cochran-Armitage trend test; p < 0.0001). Similar results were obtained for mechanical ventilation rate (moderate 9.8%, severe 16.7%, extremely severe 25.4%, Cochran-Armitage trend test; p = 0.0006). The compliance with scoring the A-DROP was higher than that with scoring the PSI (96.9 vs. 71.6%). CONCLUSIONS: The results of this study suggest that the A-DROP scoring system could be a simple CAP risk scoring system which could predict not only mortality, but also the requirement for mechanical ventilation.

The anti-inflammatory and proresolving mediator resolvin E1 protects mice from bacterial pneumonia and acute lung injury.

Whereas pneumonia is the most common cause of death and disability worldwide, most cases of pneumonia spontaneously resolve. Mechanisms that promote pneumonia resolution remain to be determined. Resolvin E1 (RvE1) is an endogenous mediator that displays proresolving actions in sterile inflammation. In this study, we developed a new model of aspiration pneumonia to evaluate the effect of RvE1 on acute lung injury caused by acid aspiration and subsequent bacterial challenge. Mice received hydrochloric acid into the left lung followed by the enteric pathogen Escherichia coli. I.v. administration of RvE1 (approximately 0.005 mg/kg) prior to acid injury selectively decreased lung neutrophil accumulation by 55% and enhanced clearance of E. coli. RvE1 significantly decreased lung tissue levels of several proinflammatory chemokines and cytokines, including IL-1beta, IL-6, HMGB-1, MIP-1alpha, MIP-1beta, keratinocyte-derived chemokine, and MCP-1, in a manner independent of the anti-inflammatory mediators IL-10 and lipoxin A4. In addition, animals treated with RvE1 had a marked improvement in survival. These findings in experimental aspiration pneumonia have uncovered protective roles for RvE1 in pathogen-mediated inflammation that are both anti-inflammatory for neutrophils and protective for host defense, suggesting that RvE1 represents the first candidate for a novel therapeutic strategy for acute lung injury and pneumonia that harnesses natural resolution mechanisms.

Reevaluation of the efficacy and safety of the neutrophil elastase inhibitor, Sivelestat, for the treatment of acute lung injury associated with systemic inflammatory response syndrome; a phase IV study.

INTRODUCTION: Sivelestat, a neutrophil elastase inhibitor, has been approved in Japan for the treatment of patients with acute lung injury (ALI) associated with systemic inflammatory response syndrome (SIRS). The Pharmaceuticals and Medical Devices Agency (PMDA) has ordered to conduct a postmarket clinical study in order to reevaluate the efficacy and safety of Sivelestat in actual clinical settings in Japan. METHODS: According to the PMDA's order, we evaluated the efficacy and safety of Sivelestat in Japanese patients with ALI associated with SIRS using ventilator-free days (VFD) as the primary endpoint. The surrogate endpoints are ventilator-weaning rate, ICU discharge rate, and 180-day survival rate. Study design was an open-label, non-randomized, multi-center clinical trial. Sivelestat was intravenously administered at 0.2 mg/kg/h continuously for a maximum of 14 days. Sivelestat group and control group were compared by adjusting the outcome values using an inverse probability of treatment weighted method based on the propensity scores. RESULTS: Four hundred and four Sivelestat group patients and 177 control group patients were enrolled. The adjusted mean number of VFD was 15.7 and 12.1 in the Sivelestat group and control group, respectively (P = 0.0022). Both the adjusted ventilator-weaning rate and ICU discharge rate were significantly higher in the Sivelestat group than in the control group (P = 0.0028 and P = 0.019, respectively). The adjusted 180-day survival rate was significantly higher in the Sivelestat group than in the control group (71.8 percent vs. 56.3 percent). CONCLUSIONS: Sivelestat contributed to early weaning from the mechanical ventilation, while showing no negative effect on the long-term outcomes of ALI associated with SIRS. The results of this study suggest the clinical usefulness of Sivelestat in this patient population.

Impact of serum high-mobility group box 1 protein elevation on oxygenation impairment after thoracic aortic aneurysm repair.

High-mobility group box 1 protein (HMGB1) is a late mediator of inflammatory responses that can cause acute lung injury. We examined the significance of serum HMGB1 elevation in the development of systemic inflammatory response syndrome (SIRS) and lung oxygenation impairment (LOI) after thoracic aortic aneurysm (TAA) repair. Serial measurements of the serum HMGB1 level and SIRS score for 7 days after surgery were determined in 20 patients with TAA who underwent surgical repair. Arterial oxygen tension was measured serially for at least 4 days after surgery, and LOI was defined as the lowest PaO(2)/FiO(2) ratio ≤ 200 mmHg. The serum HMGB1 level was markedly increased after surgery, peaking on day 2, and remained significantly elevated on day 7. Peak HMGB1 level positively correlated with SIRS duration and the cumulative SIRS score during postoperative days 1-7 (P = 0.0013 and P = 0.0004, respectively). Peak HMGB1 level and cumulative SIRS score were higher in patients with LOI than in those without (P = 0.01 and P = 0.044, respectively). Peak HMGB1 level was negatively correlated with the lowest PaO(2)/FiO(2) ratio (P = 0.0077) and positively correlated with postoperative length of hospitalization (P = 0.042). A greater serum HMGB1 elevation after TAA repair was associated with more severe SIRS and a higher incidence of LOI. HMGB1 might play a key role in the pathogenesis of SIRS and LOI after surgical TAA repair.

Plasma biomarker profiles in acute exacerbation of idiopathic pulmonary fibrosis.

Little is known about the pathobiology of acute exacerbation of idiopathic pulmonary fibrosis (IPF), a condition that shares clinical and histopathological features with acute lung injury. Plasma biomarkers have been well studied in acute lung injury and have provided insight into the underlying disease mechanism. The objective of this study was to determine the plasma biomarker profile of acute exacerbation of IPF and compare this profile with that of stable IPF and acute lung injury. Plasma was collected from patients with stable IPF, acute exacerbation of IPF, and acute lung injury for measurement of biomarkers of cellular activity/injury (receptor for advanced glycation endproducts, surfactant protein D, KL-6, von Willebrand factor), systemic inflammation (IL-6), and coagulation/fibrinolysis (protein C, thrombomodulin, plasminogen activator inhibitor-1). Plasma from patients with acute exacerbation of IPF showed significant elevations in markers of type II alveolar epithelial cell injury and/or proliferation, endothelial cell injury, and coagulation. This profile differed from the biomarker profile in patients with acute lung injury. These findings support the hypothesis that type II alveolar epithelial cells are centrally involved in the pathobiology of acute exacerbation of IPF. Furthermore, they suggest that acute exacerbation of IPF has a distinct plasma biomarker profile from that of acute lung injury.

Strain-specific phenotypes of airway inflammation and bronchial hyperresponsiveness induced by epicutaneous allergen sensitization in BALB/c and C57BL/6 mice.

BACKGROUND: Allergen sensitization through a disrupted skin barrier appears to play a prominent role in the development of atopic diseases, including allergic asthma. The role of the genetic background in immunological and physiological phenotypes induced by epicutaneous sensitization is undetermined. METHODS: BALB/c and C57BL/6 mice were sensitized either epicutaneously by patch application of ovalbumin (OVA) or systemically by intraperitoneal injection of OVA with alum before exposure to aerosolized OVA. The concentrations of OVA-specific immunoglobulin in serum and cytokines in bronchoalveolar lavage fluid (BALF) were measured by enzyme-linked immunosorbent assay. The severity of airway inflammation was evaluated by cell counts in BALF, and bronchial responsiveness to methacholine was measured by the flexiVent system. RESULTS: The production of OVA-specific IgG1 and IgE was greater in the epicutaneously sensitized BALB/c than C57BL/6 mice. In contrast, both eosinophilic airway inflammation and bronchial responsiveness to methacholine were more prominent in the C57BL/6 than in the BALB/c mice. The concentrations of interleukin-4 increased significantly in the BALF from C57BL/6 mice only. No between-strain differences were observed after intraperitoneal sensitization. CONCLUSIONS: The C57BL/6 mouse is a more appropriate model than the BALB/c mouse to study the relationship between skin barrier dysfunction and the pathogenesis of allergic asthma.

Effect of Toll-like receptor 4 inhibitor on LPS-induced lung injury.

OBJECTIVE AND DESIGN: Toll-like receptor 4 (TLR4) plays important roles in the recognition of lipopolysaccharide (LPS) and the activation of inflammatory cascade. In this study, we evaluated the effect of TAK-242, a selective TLR4 signal transduction inhibitor, on acute lung injury (ALI). MATERIALS AND METHODS: C57BL/6J mice were intravenously treated with TAK-242 15 min before the intratracheal administration of LPS or Pam3CSK4, a synthetic lipopeptide. Six hours after the challenge, bronchoalveolar lavage fluid was obtained for a differential cell count and the measurement of cytokine and myeloperoxidase levels. Lung permeability and nuclear factor-kappaB (NF-kappaB) DNA binding activity were also evaluated. RESULTS: TAK-242 effectively attenuated the neutrophil accumulation and activation in the lungs, the increase in lung permeability, production of inflammatory mediators, and NF-kappaB DNA-binding activity induced by the LPS challenge. In contrast, TAK-242 did not suppress inflammatory changes induced by Pam3CSK4. CONCLUSION: TAK-242 may be a promising therapeutic agent for ALI, especially injuries associated with pneumonia caused by Gram-negative bacteria.

Role of interleukin-6 in elastase-induced lung inflammatory changes in mice.

Interleukin-6 (IL-6) is known to be involved in the pathogenesis of various inflammatory diseases, but its role in the development of pulmonary emphysema remains unclear. Wild-type (WT) and IL-6-deficient mice received either phosphate-buffered saline (PBS) or porcine pancreatic elastase (PPE) intratracheally. The development of emphysema was determined by measuring the mean linear intercept (Lm). The lung specimens were also subjected to immunohistochemistry for single-stranded DNA to detect apoptotic cells. Lung mechanics and airway responsiveness to inhaled methacholine were analyzed. Bronchoalveolar lavage (BAL) fluid was subjected to evaluation of inflammatory cell accumulation and cytokine measurement. PPE treatment caused significant increases in Lm and lung compliance, which was attenuated by IL-6 deficiency. The increases in apoptotic cells in the lung were attenuated in IL-6 null mice. Airway responsiveness was not affected by PPE challenge or IL-6 deficiency. Intratracheal PPE increased the cell counts in BAL fluid throughout the observation, which was suppressed in IL-6 null mice. In BAL fluid, PPE-induced increases in the levels of macrophage inflammatory protein (MIP)-1alpha and eotaxin were mitigated by IL-6 deficiency. PPE-induced up-regulation of matrix metalloproteinase (MMP)-12 in the lung was attenuated by IL-6 deficiency. These results indicate that IL-6 may play an important role in the development of elastase-induced lung inflammatory changes.

Evaluation of pathogen detection from clinical samples by real-time polymerase chain reaction using a sepsis pathogen DNA detection kit.

INTRODUCTION: Sepsis is a serious medical condition that requires rapidly administered, appropriate antibiotic treatment. Conventional methods take three or more days for final pathogen identification and antimicrobial susceptibility testing. We organized a prospective observational multicenter study in three study sites to evaluate the diagnostic accuracy and potential clinical utility of the SeptiFast system, a multiplex pathogen detection system used in the clinical setting to support early diagnosis of bloodstream infections. METHODS: A total of 212 patients, suspected of having systemic inflammatory response syndrome (SIRS) caused by bacterial or fungal infection, were enrolled in the study. From these patients, 407 blood samples were taken and blood culture analysis was performed to identify pathogens. Whole blood was also collected for DNA Detection Kit analysis immediately after its collection for blood culture. The results of the DNA Detection Kit, blood culture and other culture tests were compared. The chosen antimicrobial treatment in patients whose samples tested positive in the DNA Detection Kit and/or blood culture analysis was examined to evaluate the effect of concomitant antibiotic exposure on the results of these analyses. RESULTS: SeptiFast analysis gave a positive result for 55 samples, while 43 samples were positive in blood culture analysis. The DNA Detection Kit identified a pathogen in 11.3% (45/400) of the samples, compared to 8.0% (32/400) by blood culture analysis. Twenty-three pathogens were detected by SeptiFast only; conversely, this system missed five episodes of clinically significant bacteremia (Methicillin-resistant Staphylococcus aureus (MRSA), 2; Pseudomonas aeruginosa, 1; Klebsiella spp, 1; Enterococcus faecium, 1). The number of samples that tested positive was significantly increased by combining the result of the blood culture analysis with those of the DNA Detection Kit analysis (P = 0.01). Among antibiotic pre-treated patients (prevalence, 72%), SeptiFast analysis detected more bacteria/fungi, and was less influenced by antibiotic exposure, compared with blood culture analysis (P = 0.02). CONCLUSIONS: This rapid multiplex pathogen detection system complemented traditional culture-based methods and offered some added diagnostic value for the timely detection of causative pathogens, particularly in antibiotic pre-treated patients. Adequately designed intervention studies are needed to prove its clinical effectiveness in improving appropriate antibiotic selection and patient outcomes.

Association between beta-adrenoceptor gene polymorphisms and relative response to beta 2-agonists and anticholinergic drugs in Japanese asthmatic patients.

BACKGROUND AND OBJECTIVE: Whether beta(2)-adrenoceptor gene (ADRB2) polymorphisms are associated with airway responsiveness to beta(2)-agonist medications remains controversial, partly due to factors that may confound pharmacogenetic associations, including age, cigarette smoking and airway remodelling. To overcome these problems, we performed an analysis using parameters that reflected the specific bronchodilator response to beta(2)-agonists. METHODS: The increases in FEV(1) after inhalation of procaterol hydrochloride (Delta FEV(1) procaterol) or oxitropium bromide (Delta FEV(1) oxitropium), and after sequential inhalation of procaterol and oxitropium (total airway reversibility), were measured in 81 Japanese patients with moderate to severe asthma. Approximately 3 kb of the DNA sequence of the coding and 5'-flanking regions of ADRB2 were genotyped by direct sequencing and PCR-restriction fragment length polymorphism assay. RESULTS: The mean age of the participants was 54 years, and 38 (47%) were smokers. Although Delta FEV(1) procaterol and Delta FEV(1) oxitropium adjusted for predicted FEV(1) were not associated with ADRB2 polymorphisms, the ratio of Delta FEV(1) procaterol to total airway reversibility was significantly associated with the ADRB2 A46G genotype (P < 0.05). Patients who were homozygous for the A46 allele (arginine at amino acid 16) were more responsive than carriers of the G46 (glycine 16) allele (P = 0.008). Multivariate linear regression analysis showed that Delta FEV(1) procaterol was correlated with the number of A46 alleles (P = 0.014), and also with total airway reversibility (P < 0.001) and smoking index in current smokers (P = 0.009). CONCLUSIONS: The ADRB2 A46G polymorphism was associated with a relatively greater bronchodilator responsiveness to beta(2)-agonists even in elderly asthmatic patients and smokers.

Elevated serum adiponectin level in patients with Mycobacterium avium-intracellulare complex pulmonary disease.

BACKGROUND: Patients with Mycobacterium avium-intracellulare complex (MAC) pulmonary disease often suffer from weight loss. Adipokines are factors secreted by adipocytes, including leptin and adiponectin, as well as some inflammatory cytokines, tumor necrosis factor-alpha (TNF-alpha) and interleukin 6 (IL-6). Body mass index (BMI) is known to be inversely correlated with adiponectin and positively with leptin, TNF-alpha, and IL-6. OBJECTIVE: We aimed to evaluate the levels of serum adipokines, including adiponectin, leptin, TNF-alpha, and IL-6 in patients with MAC pulmonary disease. METHODS: Forty consecutive patients with MAC pulmonary disease (8 males; median age 62 years; median BMI 18.1) were examined. Serum levels of adiponectin, leptin, TNF-alpha, and IL-6 were measured with ELISA. Age-, sex- and BMI-matched healthy subjects served as controls. RESULTS: Serum adiponectin was significantly elevated in patients with MAC pulmonary disease compared with the controls (p < 0.01). In both the patients and controls, serum adiponectin levels were inversely correlated with BMI (p < 0.05). No significant correlation was observed between serum adiponectin levels and C-reactive protein or lung function. Serum leptin levels, which were positively correlated with BMI, did not differ between patients and controls. Serum levels of TNF-alpha and IL-6 were significantly greater in patients with MAC pulmonary disease than in controls. The levels of TNF-alpha and IL-6 were not correlated with BMI and other adipokines examined. CONCLUSION: The results of the present study indicate that, in patients with MAC pulmonary disease, adiponectin is inappropriately secreted and may play a role in the pathophysiology of the disease.

High-mobility-group box chromosomal protein 1 as a new target for modulating stress response.

Major surgical procedures induce a systemic inflammatory response syndrome (SIRS) characterized by the overproduction of proinflammatory cytokines, which induces excessive stress and may trigger postoperative complications. This has prompted the hypothesis that drugs which relieve SIRS might improve the postoperative course of major surgery. One of the most promising targets for these drugs is high-mobility-group box chromosomal protein 1 (HMGB1). In 1999, HMGB1 was found to be a key late mediator of sepsis. It is now known to be associated with various kinds of acute and chronic inflammation, and is recognized as one of the most important danger signals in stress response. In this article, we present the latest information about HMGB1 and discuss its promise as a novel target for modulating stress response.

[A case of miliary tuberculosis showing acute respiratory distress syndrome in rheumatoid arthritis].

A 62-year-old man, treated with corticosteroids and immunosuppressants for rheumatoid arthritis, visited hospital with high fever and dyspnea on exertion. A CT scan of the chest demonstrated bilateral diffuse ground glass opacities. On the basis of the findings of the CT scan, he was initially given a diagnosis of interstitial pneumonia. He was then referred to our hospital and admitted to the intensive care unit (ICU), where because of progressive respiratory failure, he was put on mechanical ventilation. A bronchoscopy specimen after intubation turned out to be positive for acid-fast bacilli, which were confirmed to be mycobacterium tuberculosis by a polymerase chain reaction test. He was given a diagnosis of miliary tuberculosis complicated with acute respiratory distress syndrome (ARDS). He died of respiratory failure despite treatment with antituberculosis drugs. The autopsy revealed necrotizing epithelioid granulomas in both lungs, mediastinal lymph nodes, the liver, both kidneys, vertebrae and other organs. Diffuse alveolar damage was also found in both lungs. It is often difficult to detect disseminated nodules in the miliary tuberculosis with ARDS. Miliary tuberculosis should be suspected in patients in an immunosuppressant state with rheumatoid arthritis, and who have respiratory symptoms or fever of unknown origin.

[Long-term treatment with a humanized anti-interleukin-6 receptor antibody (tocilizumab), improving interstitial pneumonia in a patient with multicentric Castleman disease].

A 46-year-old man was admitted for the evaluation of a dry cough and dyspnea on exertion. Laboratory tests revealed anemia, elevated CRP, polyclonal hyperimmunoglobulinemia, and an elevated interleukin-6 level. Radiological examination of the chest showed peribronchovascular consolidations, ground glass opacities, small nodular opacities, and interlobular septal thickenings in the lungs, accompanied with hilar and mediastinal lymphadenopathies. A video-assisted thoracoscopic lung and mediastinal lymph node biopsy revealed plasmacytic and lymphocytic infiltration around the bronchovascular bundles of the lungs, and plasmacytic infiltration in the interfollicular areas of the nodes. Based on these findings, a diagnosis of multicentric Castleman disease was confirmed. The patient received a humanized anti-interleukin-6 receptor antibody, (tocilizumab, 8 mg/kg), every 2 weeks for 3 years, during which time, his PaO2 level improved from 64.1 Torr to 83.4 Torr, vital capacity increased from 2.53 L to 3.95 L, and radiological abnormalities in the lungs gradually improved, suggesting that tocilizumab is effective for interstitial pneumonia in patients with multicentric Castleman disease.

High-mobility group box 1 contributes to lethality of endotoxemia in heme oxygenase-1-deficient mice.

High-mobility group box 1 (HMGB1) is a nuclear protein that has been found to be a critical mediator of lethality in endotoxemia and sepsis. During the systemic inflammatory response, circulating levels of HMGB1 are increased, but in a delayed fashion compared with early inflammatory mediators. To counteract the inflammatory response of endotoxemia, a secondary anti-inflammatory response ensues in an attempt to prevent inflammation-induced tissue injury. One such cytoprotective gene that is induced during endotoxemia is heme oxygenase (HO)-1. HO-1, and its products of heme metabolism, possess anti-inflammatory and antioxidant properties to counter the damaging effects of endotoxemia. In the present study, we wanted to determine whether tissue and circulating levels of HMGB1 are increased further in the absence of HO-1 during endotoxemia, and whether this increase may contribute to the pathobiology of endotoxemia. Lung inflammation, HMGB1 protein levels, and expression of HMGB1 in inflammatory cells were increased in HO-1(-/-) mice compared with HO-1+/+ mice. After the administration of LPS, tissue levels of HMGB1 were not increased further in HO-1(-/-) mice; however, circulating levels of HMGB1 were higher when compared with HO-1+/+ mice. HO-1(-/-) mice treated with a carbon monoxide-releasing molecule or biliverdin showed a reduction in plasma HMGB1, which was associated with a marked improvement in survival. HO-1(-/-) mice given HMGB1-neutralizing antibody showed improvement in survival compared with control antibody. These data suggest that exaggerated circulating levels of HMGB1 contribute to endotoxin-induced mortality in the absence of HO-1.

Serodiagnostic contributions of antibody titers against mycobacterial lipid antigens in Mycobacterium avium complex pulmonary disease.

BACKGROUND: Although the incidence of pulmonary tuberculosis is decreasing, the number of immunocompetent patients with Mycobacterium avium complex (MAC) pulmonary disease is steadily increasing. Therefore, albeit not contagious, MAC pulmonary disease needs to be diagnosed rapidly and accurately. We examined the serodiagnostic contributions of serum immunoglobulin G antibody titers against the species-specific and -common mycobacterial lipid antigens in the diagnosis of MAC pulmonary disease. METHODS: Serum samples were obtained from 65 patients with MAC pulmonary disease, 15 patients with suspected MAC disease, 25 patients with pulmonary tuberculosis, 10 patients with Mycobacterium kansasii disease, and 100 healthy volunteers (control subjects). We measured the serum immunoglobulin G antibody titers against trehalose monomycolate (TMM-M) and apolar-glycopeptidolipid (GPL), lipid antigens extracted from MAC. RESULTS: In patients with MAC pulmonary disease, the antibody titers against TMM-M and apolar-GPL were significantly higher than those in the other patient groups or in the control subjects. By receiver operator characteristic curve analysis, an optical density of 0.27, corresponding to the optimal cutoff antibody titer against TMM-M, was associated with a sensitivity of 89.2% and a specificity of 97.0%, and an optical density of 0.33, corresponding to the optimal cutoff antibody titer against apolar-GPL, was associated with a sensitivity of 89.2% and a specificity of 94.0%. CONCLUSIONS: Measurements of antibody titers against TMM-M and apolar-GPL would be useful in the diagnosis of MAC pulmonary disease and in the differential diagnosis of mycobacterial pulmonary disease.

Comparison of the pharmacodynamics of biapenem in bronchial epithelial lining fluid in healthy volunteers given half-hour and three-hour intravenous infusions.

The time above the MIC (T>MIC) is the pharmacokinetic/pharmacodynamic (PK/PD) parameter that correlates with the therapeutic efficacy of beta-lactam antibiotics. A prolonged infusion can provide plasma drug concentrations that remain above the MIC for a long period. The objective of this study was to compare the PK/PD parameters in bronchial epithelial lining fluid (ELF) of biapenem given as 0.5-h and 3-h infusions by using bronchoscopic microsampling (BMS). Six healthy adult volunteers received 0.5-h and 3-h infusions of 0.3 g of biapenem with a washout interval. BMS was performed repeatedly from 0.5 to 24 h after biapenem administration in order to determine the pharmacokinetics in bronchial ELF. The subjects received intravenous biapenem with the same regimens again and then underwent bronchoalveolar lavage (BAL) at the end of infusion in order to determine the concentration of the drug in alveolar ELF. The percentages (means +/- standard deviations) of T>MIC in bronchial ELF at MICs from 0.25 to 4 microg/ml ranged from zero to 34.6% +/- 5.2% after the 0.5-h infusion and from 5.1% +/- 5.6% to 52.2% +/- 17.0% after the 3-h infusion. The percentage of T>MIC in bronchial ELF after the 3-h infusion tended to be higher than that after the 0.5-h infusion. The concentrations of the drug in alveolar ELF after 0.5-h and 3-h infusions were 3.5 +/- 1.2 microg/ml and 1.3 +/- 0.3 microg/ml, respectively. The present results support the use of prolonged infusions of beta-lactam antibiotics and may provide critical information for successful treatment of lower respiratory tract infections based on PK/PD parameters in bronchial ELF.

Tumor necrosis factor-alpha mediates hyperglycemia-augmented gut barrier dysfunction in endotoxemia.

OBJECTIVE: To examine whether hyperglycemia would augment gut barrier dysfunction and inflammatory responses in endotoxemic rats, and simultaneously to clarify the roles of tumor necrosis factor (TNF)-alpha in alterations of gut mucosal permeability associated with hyperglycemia. DESIGN: Prospective randomized animal study. SETTING: University research laboratory. SUBJECTS: : Male Wistar rats treated with lipopolysaccharide (LPS) injection. INTERVENTIONS: After LPS injection (4 mg/kg), rats were randomly allocated into group S (n = 6), group G (n = 7), or group GI (n = 8) with continuous infusion of different fluid solutions: normal saline, 40% glucose or 10% glucose mixed with insulin, respectively. Blood glucose, insulin, and proinflammatory cytokines, accompanied by gut mucosal permeability using an in situ loop preparation of gut with fluorescence isothiocyanate-conjugated dextran, were measured. Bacterial growth or alterations in mesenteric lymph nodes and cecal contents were also assessed. We further determined the roles of TNF-alpha using an inhibitor of TNF-alpha converting enzyme in gut barrier dysfunction under the same experimental settings. MEASUREMENTS AND MAIN RESULTS: Hyperglycemia over 400 mg/dL was achieved and kept in group G during the study period whereas normoglycemia was preserved in group S and GI, the latter of which showed the similar extent of hyperinsulinemia to group G. Plasma concentrations of fluorescence-labeled dextran and TNF-alpha in group G were significantly higher vs. group S and GI, and the number of bacteria found in mesenteric lymph nodes in group G was greater compared with group S. Intestinal environments including microflora and organic acids were not altered by blood glucose or insulin level. Inhibiting conversion of membrane-bound to soluble type of TNF-alpha restored gut mucosal permeability augmented by hyperglycemia. CONCLUSIONS: These findings indicate that hyperglycemia deteriorates LPS-elicited gut barrier dysfunction and bacterial translocation independently of plasma insulin level, and that TNF-alpha mediates such mucosal dysfunction of gut in endotoxemia.

Macrophage derived chemokine (CCL22), thymus and activation-regulated chemokine (CCL17), and CCR4 in idiopathic pulmonary fibrosis.

BACKGROUND: Idiopathic pulmonary fibrosis (IPF) is a chronically progressive interstitial lung disease of unknown etiology. Previously, we have demonstrated the selective upregulation of the macrophage-derived chemokine CCL22 and the thymus activation-regulated chemokine CCL17 among chemokines, in a rat model of radiation pneumonitis/pulmonary fibrosis and preliminarily observed an increase in bronchoalveolar (BAL) fluid CCL22 levels of IPF patients. METHODS: We examined the expression of CCR4, a specific receptor for CCL22 and CCL17, in bronchoalveolar lavage (BAL) fluid cells, as well as the levels of CCL22 and CCL17, to elucidate their pathophysiological roles in pulmonary fibrosis. We also studied their immunohistochemical localization. RESULTS: BAL fluid CCL22 and CCL17 levels were significantly higher in patients with IPF than those with collagen vascular diseases and healthy volunteers, and there was a significant correlation between the levels of CCL22 and CCL17 in patients with IPF. CCL22 levels in the BAL fluid did not correlate with the total cell numbers, alveolar lymphocytes, or macrophages in BAL fluid. However, the CCL22 levels significantly correlated with the numbers of CCR4-expressing alveolar macrophages. By immunohistochemical and immunofluorescence analysis, localization of CCL22 and CCR4 to CD68-positive alveolar macrophages as well as that of CCL17 to hyperplastic epithelial cells were shown. Clinically, CCL22 BAL fluid levels inversely correlated with DLco/VA values in IPF patients. CONCLUSION: We speculated that locally overexpressed CCL22 may induce lung dysfunction through recruitment and activation of CCR4-positive alveolar macrophages.