Seitaro Fujishima

Neutrophil-mediated tissue injury and its modulation.

Neutrophils play a key role in the development of the systemic inflammatory response syndrome (SIRS) and multiple organ dysfunction syndrome (MODS). Since the lungs are the main target in these syndromes, with adult respiratory distress syndrome (ARDS) as the outcome, extensive research has been undertaken to prevent or mitigate ARDS. As evidence of the involvement of neutrophils in ARDS has accumulated, modulation of their function has become a major goal in terms of a therapeutic approach. In this short review, we sought to update our knowledge about neutrophils. Firstly, we summarized the various stimuli which activate neutrophils. Secondly, we described the different mediators, including cytokines, which are released by neutrophils. Lastly, we discussed the possible modulation of their function. Although we cannot assess the clinical usefulness of biochemical substances merely on the basis of their in vitro effects, understanding these mechanisms is fundamental to the success of the new therapeutic approach which is currently under way.

Genetic variants of NRAMP1 and active tuberculosis in Japanese populations

To the Editor: Tuberculosis is a major public health concern worldwide. Approximately 30% of world’s population is infected with Mycobacterium tuberculosis, and 3000000 people die as a consequence each year. While significant exposure and socioeconomic factors are key elements in the development of tuberculosis, intrinsic host factors, especially genetic susceptibility to this pathogen, are important. Studies of mycobacterial infections in animal models provide compelling evidence for a genetic component of host resistance/susceptibility to this bacillus (1). Early animal experiments identified a single dominant gene, designated Bcg (2). A candidate gene was identified and designated as the natural-resistance-associated-macrophage protein 1 gene (Nramp1) (2). The human homologue of NRAMP1 has been cloned (3, 4) and it is localised on chromosome 2q35 (4). To date, 11 variants including five coding regions, three in the introns, and two in the 3% non-coding region have been identified (5, 6). Early attempts to find a genetic linkage between NRAMP1 and tuberculosis failed (7), but a significant genetic association was found between four variants of NRAMP1 and active M. tuberculosis in west Africans (8). To test whether variants of NRAMP1 relate to active tuberculosis in Japanese populations, we conducted a genetic association study using two independent populations from Tokyo and Osaka. Controls were randomly selected from clients in a commercial medical examination company (9). All patients were newly diagnosed cases of pulmonary tuberculosis, with positive acid-fast bacilli showing in sputum smear specimens; none of them was HIV-positive. We first genotyped 30 patients from each of the two populations for 5% promoter (GT)n (8), INT4 (intron 4) (5), Asn543Asp (5), and 3% untranslated region (UTR) variants (8), previously tested by Bellamy et al. (8); we found that the former two and the latter two were in perfect linkage disequilibrium in our populations, as described (5, 8). We thus focused on genotyping the 5% promoter (GT)n and Asn543Asp variants (5, 8); three alleles, 199bp (designated as allele 1), 201bp (allele 2), and 203bp (allele 3) (10) were identified and imaged by automated sequencer (ABI 310) (5). A weak association was found between Asn543Asp and tuberculosis in the Tokyo population; in contrast, there was a significant association with the 5% promoter (GT)n in both populations (Table 1). Of the four (GT)n alleles, allele 3 has been shown to drive promoter activity after stimulation with lipopoysaccharide, or interferon-g, while alleles 1 and 2 reduce it (10); poor promoter alleles (1 and 2), especially allele 1, thus showed a significantly stronger association with tuberculosis in both populations (Table 1); furthermore, the frequencies of homozygous allele 3 were significantly lower in both tuberculosis populations (Table 1). Since there was no significant difference in genotype frequencies between the two populations, we conducted a combined multivariate analysis on the total of 496 subjects; simple factorial analysis of variance (ANOVA) confirmed that there was no interaction between Asn543 and the 5% promoter (GT)n, and that allele 3 is a significant independent genetic marker for resistance to tuberculosis (f-value=3.24, df=2, p=0.039); by comparison, heterozygosity at the INT4 and 3% UTR loci was the highest risk factor in west Africans (8). In conclusion, we show that variants of NRAMP1 are associated with active tuberculosis in Japanese populations (combined odds ratio= 2.07, 95% confidence interval: 1.32–2.61, p= 0.0003); these findings support the first report in west Africans (8). However, the pattern of allelic association with tuberculosis is different in the

A multicenter, prospective validation study of the Japanese Association for Acute Medicine disseminated intravascular coagulation scoring system in patients with severe sepsis

IntroductionTo validate the Japanese Association for Acute Medicine (JAAM) disseminated intravascular coagulation (DIC) scoring system in patients with severe sepsis, we conducted a multicenter, prospective study at 15 critical care centers in tertiary care hospitals.MethodsThis study included 624 severe sepsis patients. JAAM DIC was scored on the day of diagnosis of severe sepsis (day 1) and day 4. Scores for disease severity and organ dysfunction were also evaluated.ResultsThe prevalence of JAAM DIC was 46.8% (292/624), and 21% of the DIC patients were scored according to the reduction rate of platelets. The JAAM DIC patients were more seriously ill and exhibited more severe systemic inflammation, a higher prevalence of multiple organ dysfunction syndrome (MODS) and worse outcomes than the non-DIC patients. Disease severity, systemic inflammation, MODS and the mortality rate worsened in accordance with an increased JAAM DIC score on day 1. The Kaplan-Meier curves demonstrated lower 1-year survival in the JAAM DIC patients than in those without DIC (log-rank test P <0.001). The JAAM DIC score on day 1 (odds ratio = 1.282, P <0.001) and the Delta JAAM DIC score (odds ratio = 0.770, P <0.001) were independent predictors of 28-day death. Dynamic changes in the JAAM DIC score from days 1 to 4 also affected prognoses. The JAAM DIC scoring system included all patients who met the International Society on Thrombosis and Haemostasis overt DIC criteria on day 1. The International Society on Thrombosis and Haemostasis scoring system missed a large number of nonsurvivors recognized by the JAAM scoring system.ConclusionsThe JAAM DIC scoring system exhibits good prognostic value in predicting MODS and poor prognosis in patients with severe sepsis and can detect more patients requiring treatment. Conducting repeated daily JAAM scoring increases the ability to predict the patients prognosis.

The impact of body temperature abnormalities on the disease severity and outcome in patients with severe sepsis: an analysis from a multicenter, prospective survey of severe sepsis

IntroductionAbnormal body temperatures (Tb) are frequently seen in patients with severe sepsis. However, the relationship between Tb abnormalities and the severity of disease is not clear. This study investigated the impact of Tb on disease severity and outcomes in patients with severe sepsis.MethodsWe enrolled 624 patients with severe sepsis and grouped them into 6 categories according to their Tb at the time of enrollment. The temperature categories (≤35.5°C, 35.6–36.5°C, 36.6–37.5°C, 37.6–38.5°C, 38.6–39.5°C, ≥39.6°C) were based on the temperature data of the Acute Physiology and Chronic Health Evaluation II (APACHE II) scoring. We compared patient characteristics, physiological data, and mortality between groups.ResultsPatients with Tb of ≤36.5°C had significantly worse sequential organ failure assessment (SOFA) scores when compared with patients with Tb >37.5°C on the day of enrollment. Scores for APACHE II were also higher in patients with Tb ≤35.5°C when compared with patients with Tb >36.5°C. The 28-day and hospital mortality was significantly higher in patients with Tb ≤36.5°C. The difference in mortality rate was especially noticeable when patients with Tb ≤35.5°C were compared with patients who had Tb of >36.5°C. Although mortality did not relate to Tb ranges of ≥37.6°C as compared to reference range of 36.6–37.5°C, relative risk for 28-day mortality was significantly greater in patients with 35.6–36.5°C and ≤35.5°C (odds ratio; 2.032, 3.096, respectively). When patients were divided into groups based on the presence (≤36.5°C, n = 160) or absence (>36.5°C, n = 464) of hypothermia, disseminated intravascular coagulation (DIC) as well as SOFA and APACHE II scores were significantly higher in patients with hypothermia. Patients with hypothermia had significantly higher 28-day and hospital mortality rates than those without hypothermia (38.1% vs. 17.9% and 49.4% vs. 22.6%, respectively). The presence of hypothermia was an independent predictor of 28-day mortality, and the differences between patients with and without hypothermia were observed irrespective of the presence of septic shock.ConclusionsIn patients with severe sepsis, hypothermia (Tb ≤36.5°C) was associated with increased mortality and organ failure, irrespective of the presence of septic shock.Trial registrationUMIN-CTR IDUMIN000008195

Clinical and immunoregulatory effects of roxithromycin therapy for chronic respiratory tract infection.

The clinical and immunoregulatory effects of long-term macrolide antibiotic therapy for patients with chronic lower respiratory tract infections (CLRTI) were investigated. Clinical parameters and neutrophil chemotactic mediators in the epithelial lining fluid (ELF) of CLRTI patients (n = 10) were examined before and after 3 months oral administration of roxithromycin (RXM). The in vitro effects of RXM were also examined on the release of these mediators from alveolar macrophages (AM) and neutrophils. Arterial oxygen tension (p<0.05), vital capacity (VC) (p<0.001), %VC (p<0.05) and forced expiratory volume in one second (p<0.01) were improved after RXM treatment, but airway bacteria were not eradicated. Among the mediators, the levels of interleukin (IL)-8, neutrophil elastase (NE) and leukotriene B4 (LTB4) were higher in ELF than in plasma of CLRTI patients and they decreased after RXM treatment (n = 7, p<0.05 for each). RXM concentrations were significantly increased in the bronchoalveolar lavage cells of the treated patients. In in vitro experiments, RXM showed inhibitory effects on IL-8 release from AM and neutrophils. In conclusion, interleukin-8, neutrophil elastase and leukotriene B4 contribute to the neutrophilic inflammation in the airways of chronic lower respiratory tract infection patients and the clinical effects of roxithromycin may, in part, be attributable to the suppression of excess release of the chemotactic mediators from inflammatory cells.

Production and Activation of Matrix Metalloproteinase 7 (Matrilysin 1) in the Lungs of Patients With Idiopathic Pulmonary Fibrosis

CONTEXT Idiopathic pulmonary fibrosis (IPF) is characterized by diffuse interstitial inflammation and fibroblast proliferation with accelerated remodeling of extracellular matrix, which result in irreversible destruction of the lungs architecture. OBJECTIVE To elucidate the production levels, tissue localization, and activation of matrix metalloproteinase 7 (MMP-7) in the lungs of patients with IPF. DESIGN Bronchoalveolar lavage analysis was performed in 17 IPF patients and 6 healthy volunteers. Levels of MMP-7 in blood were assayed in 23 IPF patients and 20 controls. Histologic and immunohistochemical analyses were performed on paraffin sections of the lung tissues from patients with IPF, interstitial pneumonia associated with rheumatoid arthritis, or nonspecific interstitial pneumonia. RESULTS The proMMP-7 levels in bronchoalveolar lavage fluids from IPF patients were significantly higher than those from healthy controls, although there was no difference in the serum levels between the 2 groups. By immunohistochemistry, proMMP-7 was localized mainly to the hyperplastic alveolar and metaplastic bronchiolar epithelial cells in the lung tissues from IPF patients. Active MMP-7 was immunolocalized on alveolar macrophages and hyperplastic epithelial cells, which were also immunostained with antibody against CD151, a molecule associated with activation of proMMP-7. Immunoblot analysis indicated the overproduction of proMMP-7 together with a small amount of active MMP-7 in bronchoalveolar lavage fluids from IPF patients. The MMP-7 activity was detected in a cross-linked carboxymethylated transferrin film assay. CONCLUSIONS proMMP-7 is excessively produced by hyperplastic alveolar and metaplastic bronchiolar epithelial cells and activated locally in the lungs of IPF patients, suggesting that MMP-7 may contribute to the pathology of IPF.

Usefulness of procalcitonin serum level for the discrimination of severe sepsis from sepsis: a multicenter prospective study

Procalcitonin serum level has been recommended as a new marker of bacterial infectious diseases. The aim of this prospective, multicenter study was to determine the clinical usefulness of procalcitonin in differentiating patients with sepsis from those with severe sepsis. Eighty-two patients were enrolled: 20 without systemic inflammatory response syndrome (SIRS), 9 with SIRS, 34 with sepsis, and 19 with severe sepsis. The patients with severe sepsis had significantly higher procalcitonin levels (median, 36.1 ng/ml) than those with sepsis (median, 0.6 ng/ml). With a procalcitonin cutoff value of 2.0 ng/ml, sensitivity for the detection of severe sepsis and specificity for the detection of sepsis were 94.7% and 78.1%, respectively. A good correlation was found between the serum procalcitonin level and the Sepsis-Related Organ Failure Assessment (SOFA) score (r = 0.680), although no correlation was found between the C-reactive protein (CRP) level and the SOFA score. In conclusion, the procalcitonin serum level may be useful not only for aiding the diagnosis of sepsis but also for discriminating between sepsis and severe sepsis.

Elevated CC Chemokine Level in Bronchoalveolar Lavage Fluid Is Predictive of a Poor Outcome of Idiopathic Pulmonary Fibrosis

Background: CC chemokines play important roles in the pathogenesis of interstitial lung diseases. Elevated CC chemokine levels have been observed in bronchoalveolar lavage (BAL) fluid of patients with idiopathic pulmonary fibrosis (IPF). Objectives:We aimed to examine whether the levels of four CC chemokines, i.e. monocyte chemoattractant protein-1 (MCP-1/CCL2), macrophage inflammatory protein-1α (MIP-1α/CCL3), thymus- and activation-regulated chemokine (TARC/CCL17), and macrophage-derived chemokine (MDC/CCL22), in BAL fluid are predictive of the prognosis of IPF patients. Methods: We compared the chemokine levels of patients alive 5 years after diagnosis and those who had died. Lung function data, CT scores, and serum markers were also compared. Results: Among 39 patients (29 males, median age, 60 years), 19 patients (48%) died within 5 years after the diagnosis. Whereas percent vital capacity was not different, percent lung diffusion capacity for carbon monoxide was significantly higher in the surviving patients than in the nonsurviving patients (p < 0.01). Median CCL2 levels of surviving and nonsurviving patients were 154.3 (interquartile range, IQR: 67.3–381.8) and 427.2 (IQR: 329.2–1184.1) pg/ml, respectively (p < 0.02). CCL3 levels in BAL fluid did not differ between the surviving and nonsurviving patients. CCL17 was detected in BAL fluid of 7 patients, 6 of whom died within 5 years. CCL22 was detectable in BAL fluid of 10 patients, only 1 of whom survived. Serum levels of KL-6 and lactate dehydrogenase did not differ between the surviving and nonsurviving patients. Conclusion: Elevated levels of CCL2, CCL17 and CCL22 in BAL fluid might be predictive of a poor outcome in patients with IPF.

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

BackgroundIdiopathic 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.MethodsWe 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.ResultsBAL 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.ConclusionWe speculated that locally overexpressed CCL22 may induce lung dysfunction through recruitment and activation of CCR4-positive alveolar macrophages.

CCL22 and CCL17 in rat radiation pneumonitis and in human idiopathic pulmonary fibrosis

Pulmonary fibrosis is caused by various known and unknown aetiologies, but the key pathogenic mechanisms are still ill-defined. Chemokines are a large family of chemotactic cytokines that play pivotal roles in various inflammatory diseases. In the present study, the roles of chemokines in a rat model of radiation pneumonitis/pulmonary fibrosis were examined. Accumulation of inflammatory cells and pneumonitis were observed on day 28, and diffuse alveolar wall thickening with extensive fibrosis was observed on day 56. In addition to the previously reported CCL2 (macrophage chemoattractant protein‐1) induction, selective upregulation of CCL22 (macrophage-derived chemokine) and CCL17 (thymus and activation-regulated chemokine) were demonstrated for the first time in the irradiated lung tissues. Immunohistochemically, it was demonstrated that CCL22 and CCL17 were localised primarily to alveolar macrophages, whereas their receptor CC chemokine receptor 4 (CCR4) was detected on alveolar lymphocytes and macrophages. On further analysis of bronchoalveolar lavage fluid from patients with idiopathic pulmonary fibrosis and sarcoidosis, elevated levels of CCL22, but not of CCL17, were observed in the idiopathic pulmonary fibrosis patients. Since these two chemokines play pivotal roles in various type‐2 T‐helper cell-dominant diseases, it was speculated that CCL22, and probably CCL17, are involved in the pathophysiology of radiation pneumonitis/pulmonary fibrosis and idiopathic pulmonary fibrosis through the recruitment of CC chemokine receptor 4‐positive type‐2 T‐helper cells and alveolar macrophages.