Sputum Neurturin Levels in Adult Asthmatic Subjects.

Background: Neurturin (NRTN) is a neurotrophic factor that was originally identified in the development and maintenance of neural cells. Recent studies involving NRTN knockout mice have reported its anti-inflammatory effects in allergic airway conditions. However, the role of NRTN in human asthma has not yet been identified. Objective: The purposes of the present study were to confirm the presence of NRTN in the airways and to investigate the clinical and pathogenetic roles of NRTN in asthma. Methods: The NRTN levels in the induced sputum were measured by enzyme-linked immunosorbent assay (ELISA). Relationships between NRTN and clinical characteristics, asthma control status, and airway inflammation were assessed. Results: Sixty-four asthmatic subjects were enrolled in the study. All asthmatic subjects had detectable sputum NRTN levels, with a mean (SD) level of 2.03 (1.29) ng/mL. The sputum NRTN levels had significant positive correlations with sputum eosinophil and exhaled nitric oxide levels and were significantly higher in the atopic subjects than in the non-atopic subjects. No significant difference in sputum NRTN levels were observed for asthma control status and asthma exacerbation. In sputum inflammatory analyses, sputum NRTN level was positively correlated with interleukin (IL)-5 and IL-13 levels, and negatively correlated with matrix metalloproteinase (MMP)-9 level. Conclusion: It is plausible that sputum NRTN could serve as a new marker for Type 2 airway inflammation, implicating its role in the process of airway remodeling in asthma. Future studies should investigate the clinical relevance of sputum NRTN level in prospective analyses.

Comparison of fractional exhaled nitric oxide levels measured by different analyzers produced by different manufacturers.

Objective: Fractional exhaled nitric oxide (FeNO) is widely used as a biomarker of allergic airway inflammation. At present, both stationary chemiluminescence and portable electrochemical analyzers produced by different manufacturers are available. However, it remains debatable whether those analyzers are comparable to each other. We compare FeNO levels obtained by different analyzers.Methods: For the first study, 153 subjects were enrolled to compare differences in FeNO levels measured using three analyzers (NA623NP®, NObreath®, and NIOX MINO®) which were produced by different manufacturers. For the second study, 30 subjects were recruited to compare FeNO levels obtained by the two analyzers (NIOX MINO® and NIOX VERO®) produced by the same manufacturer. FeNO was measured twice using each analyzer in random order.Results: FeNO levels obtained using the NIOX MINO® and NObreath® were more variable than those measured using the NA623NP®. There were strong positive correlations in FeNO levels measured by the NA623NP®, NIOX MINO®, and NObreath® (p < 0.001). The NA623NP® and NIOX MINO® provided the highest and lowest FeNO levels, respectively; whereas, those obtained by NObreath® were intermediate. No significant differences were observed in FeNO levels obtained using the NIOX MINO® and NIOX VERO®.Conclusions: FeNO levels measured by the NIOX MINO® and NIOX VERO®, both of which were produced by the same manufacturer, have comparability. However, significant differences in FeNO levels exist when measured by analyzers manufactured by different manufacturers. This should be taken into account for FeNO measurement.

Syndecan-4 Inhibits the Development of Pulmonary Fibrosis by Attenuating TGF-ß Signaling.

Syndecan-4 is a transmembrane heparan sulfate proteoglycan expressed in a variety of cells, and its heparan sulfate glycosaminoglycan side chains bind to several proteins exhibiting various biological roles. The authors have previously demonstrated syndecan-4's critical roles in pulmonary inflammation. In the current study, however, its role in pulmonary fibrosis was evaluated. Wild-type and syndecan-4-deficient mice were injected with bleomycin, and several parameters of inflammation and fibrosis were analyzed. The mRNA expression of collagen and α-smooth muscle action (α-SMA) in lung tissues, as well as the histopathological lung fibrosis score and collagen content in lung tissues, were significantly higher in the syndecan-4-deficient mice. However, the total cell count and cell differentiation in bronchoalveolar lavage fluid were equivalent between the wild-type and syndecan-4-deficient mice. Although there was no difference in the TGF-ß expression in lung tissues between the wild-type and syndecan-4-deficient mice, significantly more activation of Smad3 in lung tissues was observed in the syndecan-4-deficient mice compared to the wild-type mice. Furthermore, in the in vitro experiments using lung fibroblasts, the co-incubation of syndecan-4 significantly inhibited TGF-ß-induced Smad3 activation, collagen and α-SMA upregulation. Moreover, syndecan-4 knock-down by siRNA increased TGF-ß-induced Smad3 activation and upregulated collagen and α-SMA expression. These findings showed that syndecan-4 inhibits the development of pulmonary fibrosis, at least in part, through attenuating TGF-ß signaling.

Serum decorin is a potential prognostic biomarker in patients with acute exacerbation of idiopathic pulmonary fibrosis.

BACKGROUND: Decorin is a small leucine-rich repeat proteoglycan that plays a critical role in collagen fibrillogenesis, and regulates inflammation, wound healing and angiogenesis. In idiopathic pulmonary fibrosis (IPF), decorin is expressed in fibrotic lesions; furthermore, intratracheal gene transfer of decorin has been demonstrated to inhibit bleomycin-induced pulmonary fibrosis. Although these results suggest the critical role of decorin in pulmonary fibrosis, the role of decorin in the acute exacerbation of idiopathic interstitial pneumonia (AE-IIP) has not been clarified in detail. Thus, the goal of this study was to determine the role of decorin in AE-IIP. METHODS: We retrospectively analyzed AE-IIP patients who had been admitted to our hospital. First, serum decorin levels were compared among patients with AE-IIP, patients with stable idiopathic interstitial pneumonia (SD-IIP), and healthy subjects. Next, the relationship between serum decorin levels and clinical parameters was analyzed in AE-IIP patients. Finally, the association between serum decorin levels and prognosis was evaluated in AE-IIP patients. IIP was divided into IPF and non-IPF, according to the published guidelines. RESULTS: The serum decorin levels of AE-IIP patients were significantly lower than those of both healthy subjects and SD-IIP patients. Serum decorin levels were not related with the clinical parameters and prognosis, when all IIP patients were analyzed. In IPF patients, serum decorin levels had a significant correlation with oxygenation, and IPF patients with low serum decorin levels had a significantly higher survival rate than those with high serum decorin levels. CONCLUSIONS: Serum decorin levels are a potential prognostic biomarker in AE-IPF.

Involvement of midkine in the development of pulmonary fibrosis.

Midkine is a low-molecular-weight heparin-binding protein that is strongly expressed mainly in the midgestation period and has various physiological activities such as in development and cell migration. Midkine has been reported to be strongly expressed in cancer cells and in inflammation and repair processes, and to be involved in the pathogenesis of various diseases. However, its role in the lung is poorly understood. In this study, we analyzed the clinical characteristics of idiopathic pulmonary fibrosis patients in relation to midkine expression and used a mouse bleomycin-induced pulmonary fibrosis model to investigate the role of midkine in pulmonary fibrosis. In the idiopathic pulmonary fibrosis patients, the serum midkine level was significantly higher than in healthy subjects, and midkine levels in the serum and bronchoalveolar lavage (BAL) fluid correlated positively with the percentage of inflammatory cells in the BAL fluid. In wild-type mice, intratracheal bleomycin administration increased midkine expression in lung tissue. Additionally, compared with wild-type mice, midkine-deficient mice showed low expression of both collagen and α-smooth muscle actin, as well as a low value for the pathological lung fibrosis score after bleomycin administration. Furthermore, the total cell count and lymphocyte percentage in the BAL fluid, as well as TNF-α and transforming growth factor-ß expression in lung tissue, were significantly lower in the midkine-deficient mice compared with wild-type mice. These results suggest that midkine is involved in the development of pulmonary fibrosis by regulating inflammatory cell migration into the lung, and TNF-α and transforming growth factor-ß expression.

Increased detection of clinically significant antibodies and decreased incidence of delayed haemolytic transfusion reaction with the indirect antiglobulin test potentiated by polyethylene glycol compared to albumin: a Japanese study.

BACKGROUND: The indirect antiglobulin test (IAT) can be potentiated by agents such as polyethylene glycol (PEG-IAT) and albumin (Alb-IAT). PEG-IAT is generally regarded as superior to Alb-IAT for the detection of clinically significant red blood cell (RBC) antibodies. However, supporting data come from Caucasian-dominant populations. Non-Caucasian populations should be investigated as well. MATERIAL AND METHODS: In this single-centre, retrospective, sequential study, Alb-IAT was used from 1989 to 1996 (8 years) and PEG-IAT from 1997 to 2008 (12 years). Pre-transfusion RBC alloantibody detection rates and specificity, post-transfusion alloantibody production, and the incidence of delayed haemolytic transfusion reaction were assessed and compared for the two periods. RESULTS: Although overall RBC alloantibody detection rates were comparable, PEG-IAT more frequently detected clinically significant antibodies such as anti-E, anti-Fy(b), and anti-Jk(a), and less frequently detected insignificant antibodies such as anti-Le(b) and anti-P(1). New alloantibodies emerged comparably during the two periods. Delayed haemolytic transfusion reaction was less frequent during the PEG-IAT period (0.30% versus 0.12%, p<0.05). CONCLUSION: PEG-IAT was superior in the detection of clinically significant antibodies, reduced the detection of insignificant antibodies, and prevented delayed haemolytic transfusion reaction better than Alb-IAT among Japanese transfusion recipients in this retrospective survey of limited power.