High concentrations of beta-chemokines in BAL fluid of patients with diffuse panbronchiolitis

HLA-B54 is an independent risk factor for pneumonia in Japanese patients with interstitial lung disease: A multicenter retrospective cohort study

PURPOSE

Pneumonia is a major cause of respiratory-related hospitalization and an important prognostic factor in patients with chronic interstitial lung disease (ILD). However, the relationship between the incidence of pneumonia and human leukocyte antigen (HLA) serotype has not been fully elucidated. Therefore, this study aimed to determine if there is a relationship between HLA serotype and the incidence of pneumonia in Japanese patients with ILD.

METHODS

The medical records of patients with ILD treated at any of three centers in Japan were reviewed to determine their HLA-A and HLA-B serotypes. The characteristics of patients with and without pneumonia were compared. Cox regression analysis was performed to identify risk factors for pneumonia and death in these patients.

RESULTS

One hundred and forty-four patients with ILD (pneumonia group, n = 27; non-pneumonia group, n = 117) and complete HLA serology data available were included. HLA-B54 positivity was significantly more common in the pneumonia group than in the non-pneumonia group (37.0% vs. 15.4%, p = 0.010). HLA-B54 positivity was also a significant risk factor for pneumonia (hazard ratio [HR] 4.166, 95% confidence interval [CI] 1.862-9.320, p = 0.001) and death (HR 4.050, 95% CI 1.581-10.374, p = 0.004) in patients with ILD. Furthermore, HLA-B54 positivity was a significant risk factor for pneumonia (HR 3.964, 95% CI 1.392-11.090, p = 0.010) and death (HR 8.131, 95% CI 1.763-37.494, p = 0.007) in patients with idiopathic pulmonary fibrosis.

CONCLUSION

HLA-B54 positivity was a significant risk factor for pneumonia and death in patients with ILD, including those with idiopathic pulmonary fibrosis.

Azithromycin treats diffuse panbronchiolitis by targeting T cells via inhibition of mTOR pathway

Azithromycin (AZM), that is a macrolide antibiotic, has been found to treat diffuse panbronchiolitis (DPB) effectively. However, the mechanism of action underlying the therapeutic effects remains unclear. We selected 64 patients with DPB from 305 patients who were diagnosed with DPB at the outpatient clinic in Shanghai Pulmonary Hospital from Jan 2010 to Oct 2014. The primary PBLs, CD4 + T cells, and Jurkat T cells were treated with AZM or erythromycin (EM), and the effects of AZM and EM on IL-17A and CXCL-2 production, proliferation, apoptosis and autophagy were evaluated. AZM and EM significantly inhibited IL-17A and CXCL-2 production in patients' PBLs (all P < 0.05). AZM significantly inhibited proliferation and promoted apoptosis of T cells from DPB patients. AZM can enhance autophagosome formation of T cells by suppressing S6RP phosphorylation, which is a downstream target of mTOR pathway (all P < 0.05). AZM and EM significantly decreased secreted IL-17A levels (P < 0.05) in the primary CD4 + T cells of patients with DPB. AZM may treat DPB patients by targeting cytokine production, proliferation, apoptosis and autophagy of T cell. The mechanism of therapeutic effects of AZM on DPB may be associated with a specific inhibition of mTOR pathway in the T lymphocytes.

Diffuse panbronchiolitis after humanized anti-CCR4 monoclonal antibody therapy for relapsed adult T-cell leukemia/lymphoma

We present the case of a 62-year-old Japanese woman with relapsed adult T-cell leukemia/lymphoma (ATLL) who was treated with humanized anti-CCR4 monoclonal antibody (KW-0761). Although this antibody was highly effective against refractory ATLL, 6 months after the final KW-0761 infusion, the patient complained of hypoxia due to diffuse panbronchiolitis. Physicians should remain vigilant to the possibility of such previously unreported late-onset adverse effects associated with KW-0761 therapy.

Diffuse Panbronchiolitis

Diffuse panbronchiolitis (DPB) is characterized by chronic sinobronchial infection and diffuse bilateral micronodular pulmonary lesions consisting of inflammatory cells. Studies on disease etiology point to a genetic predisposition unique to Asians. Early therapy for DPB was largely symptomatic. The advent of macrolide antibiotics, including erythromycin, roxithromycin and clarithromycin, has strikingly changed disease prognosis. Low-dose, long-term macrolide therapy for DPB originated from detailed observations of response to therapy in a single patient. The bactericidal activity of macrolides, particularly erythromycin, is not a significant factor for their clinical efficacy in DPB. Firstly, irrespective of bacterial clearance, clinical improvement is observed in patients treated with erythromycin. Secondly, even in cases with bacterial superinfection with Pseudomonas aeruginosa resistant to macrolides, treatment has proved effective. Thirdly, the recommended dosage of macrolides produces peak levels in tissue that are below the minimum inhibitory concentrations for major pathogenic bacteria that colonize the airway. In the last two decades, the possible mechanism underlying the effectiveness of macrolide therapy has been extensively studied. The proposed mechanism of action includes inhibition of excessive mucus and water secretion from the airway epithelium, inhibition of neutrophil accumulation in the large airway, inhibition of lymphocyte and macrophage accumulation around the small airway, and modulation of bacterial virulence. The great success of macrolide therapy in diffuse panbronchiolitis may extend its application to the treatment of other chronic inflammatory disorders. If the anti-inflammatory activity of macrolides is independent of their bactericidal effect, new anti-inflammatory macrolides without antimicrobial activity should be developed to minimize emergence of macrolide-resistant micro-organisms.

Role of macrolide therapy in chronic obstructive pulmonary disease

Chronic obstructive pulmonary disease (COPD) is a leading cause of death and disability worldwide. The Global Burden of Disease study has concluded that COPD will become the third leading cause of death worldwide by 2020, and will increase its ranking of disability-adjusted life years lost from 12th to 5th. Acute exacerbations of COPD (AECOPD) are associated with impaired quality of life and pulmonary function. More frequent or severe AECOPDs have been associated with especially markedly impaired quality of life and a greater longitudinal loss of pulmonary function. COPD and AECOPDs are characterized by an augmented inflammatory response. Macrolide antibiotics are macrocyclical lactones that provide adequate coverage for the most frequently identified pathogens in AECOPD and have been generally included in published guidelines for AECOPD management. In addition, they exert broad-ranging, immunomodulatory effects both in vitro and in vivo, as well as diverse actions that suppress microbial virulence factors. Macrolide antibiotics have been used to successfully treat a number of chronic, inflammatory lung disorders including diffuse panbronchiolitis, asthma, noncystic fibrosis associated bronchiectasis, and cystic fibrosis. Data in COPD patients have been limited and contradictory but the majority hint to a potential clinical and biological effect. Additional, prospective, controlled data are required to define any potential treatment effect, the nature of this effect, and the role of bronchiectasis, baseline colonization, and other cormorbidities.

Clarithromycin and azithromycin induce apoptosis of activated lymphocytes via down-regulation of Bcl-xL

To evaluate the anti-inflammatory action of macrolide antibiotics, we examined whether macrolide antibiotics could induce apoptosis of activated lymphocytes. The proportion of apoptotic cells was augmented by clarithromycin (CLR) and azithromycin (AZM) compared with control. There was no significant difference in Fas and Fas-ligand expression between the control and macrolide-treated groups. CLR and AZM inhibited the expression of Bcl-xL compared with that of control. Our results suggest that CLR and AZM enhance apoptosis of activated lymphocytes by down-regulation of Bcl-xL.

Differential effects of alpha- and beta-defensin on cytokine production by cultured human bronchial epithelial cells

Defensins are cysteine-rich cationic antimicrobial peptides that play an important role in innate immunity and are known to contribute to the regulation of host adaptive immunity. In addition to direct antimicrobial activities, it has been recently reported that alpha-defensins, mainly present in neutrophils in the lung, have a cytotoxic effect and induce IL-8 production from airway epithelial cells. Although beta-defensins are expressed in epithelial cells in various tissues, including lung, there are no reports of their effects on cytokine synthesis in airway epithelial cells. The aim of the present study was to determine the effects of both alpha- and beta-defensins on the cytokine production, transcription factor binding activity, and cytotoxicity in primary cultured human bronchial epithelial cells (HBECs). We used human neutrophil peptide-1 (HNP-1; alpha-defensin) and human beta-defensin-2 (HBD-2) to stimulate HBECs. The results showed that treatment of HBECs with HNP-1, but not HBD-2, increased IL-8 and IL-1beta mRNA expression in a dose-dependent manner and also enhanced IL-8 protein secretion and NF-kappaB DNA binding activity. The 24-h treatments with >20 microg/ml of HNP-1 or >50 microg/ml of HBD-2 were cytotoxic to HBECs. These results suggest that alpha- and beta-defensins have different effects on cytokine synthesis by airway epithelial cells, and we speculate that they play different roles in inflammatory lung diseases.

Applying lessons learned in the treatment of diffuse panbronchiolitis to other chronic inflammatory diseases

In addition to having antibacterial effects, macrolides modulate inflammatory responses. Their effectiveness in treating chronic inflammatory airway disease is well documented in patients with diffuse panbronchiolitis (DPB), a chronic condition characterized by inflammation of the airways that, if left untreated, progressively leads to respiratory failure and death. Long-term treatment with certain macrolides has dramatically improved the survival of patients with DPB. The mechanisms of action for the anti-inflammatory properties of macrolides are still being studied. The effects of macrolides on inflammation include decreasing chemotaxis of neutrophils to the respiratory tract and inhibiting the expression of adhesion molecules, with decreased infiltration of neutrophils into the respiratory epithelium. Macrolides also inhibit expression of transcription factors and formation of proinflammatory cytokines, and directly and indirectly block mucus secretion. Even with long-term use, macrolides are safe and well tolerated. The effectiveness of macrolides for treating DPB has led to interest in their use in treating other chronic inflammatory airway diseases. As discussed in this article, because of the similarities between the clinical presentation of cystic fibrosis and chronic bronchitis and DPB, the effects of macrolides in patients with these diseases are currently being studied with particular interest.

High-BAL fluid concentrations of RANTES in nonspecific interstitial pneumonia compared with usual interstitial pneumonia

Chemokines such as regulated on activation, normal T-cell expressed and secreted (RANTES), monocyte chemoattractant protein (MCP)-1, monocyte inflammatory protein (MIP)-lalpha have been reported to play an important role in the pathogenesis of interstitial lung diseases. Among idiopathic interstitial pneumonia (IIP), nonspecific interstitial pneumonia (NSIP) has elevated percentages of Lymphocytes in bronchoalveolar lavage (BAL) fluid compared with usual interstitial pneumonia (UIP). These chemokines are candidate mediators for lymphocyte attraction to the lung in NSIR Therefore, we measured the BAL fluid levels of RANTES, MCP-1 and MIP1-alpha in 15 patients with idiopathic NSIP, 20 with idiopathic UIP, 22 with sarcoidosis and 12 healthy volunteers to evaluate the contribution of these chemokines using enzyme-linked immunosorbent assays. The levels of RANTES in BAL fluid were significantly higher in patients with NSIP compared with healthy volunteers (P < 0.01), UIP and sarcoidosis (P < 0.05). In MCP-1, the levels in BAL fluid of NSIP and UIP patients were significantly elevated compared with healthy volunteers and sarcoidosis patients (P < 0.01). These results suggest that RANTES and MCP-1 in BAL fluid may play an important role in inflammatory cell recruitment to the lung in idiopathic NSIP as well as other interstitial lung diseases.

Influence of human T lymphotrophic virus type I on diffuse pan-bronchiolitis

Human T lymphotrophic virus type-I (HTLV-I), a human retrovirus, infects CD4(+) lymphocytes and is thought to modify their function and a possible association with pulmonary diseases has also been suggested. However, little is known about the influence of HTLV-I on diffuse pan-bronchiolitis (DPB), a chronic inflammatory lung disease with infiltration of lymphocytes and hyperplasia of the bronchus-associated lymphoid tissue. In this study, 35 DPB patients with and without HTLV-I infection were examined. HTLV-I positive DPB patients were likely to have a larger affected area with lower FEV(1). The CD3(+)/CD25(+) lymphocyte percentage was significantly higher in the BALF of HTLV-I positive patients than in negative patients. MIP-1 alpha, IP-10 and levels in BALF were also significantly higher in HTLV-I positive patients than in negative patients. The levels of MCP-1 and IL-8 were not significantly different. In HTLV-I positive patients, the MIP-1 alpha and IP-10 levels showed a significant positive correlation with the percentage of CD3(+)/CD25 lymphocytes. BALF cells of all HTLV-I positive DPB patients showed expression of p40(tax) mRNA. We suggest that HTLV-I infection may modify DPB pathogenesis via activation of T cells. We also found that the frequency of ATL development in HTLV-I positive DPB patients was significantly higher than in all HTLV-I positive patients (OR = 8.22, 95% CI = 2.61-25.9, P < 0.01). The levels of TGF-beta in patients who developed ATL were significantly lower than in patients who did not develop ATL. Sensitivity and specificity were 80% and 85.7%, respectively (cut-off = 20 pg/ml). We also propose that these features should be taken into consideration in the treatment of DPB in HTLV-I infected individuals.

Clinical similarities and differences between human T-cell lymphotropic virus type 1-associated bronchiolitis and diffuse panbronchiolitis

STUDY OBJECTIVES

Human T-cell lymphotropic virus type 1 (HTLV-1)-associated bronchiolitis and diffuse panbronchiolitis might overlap. We examined whether these conditions can be differentiated by comparing their clinical features and the effect of long-term macrolide treatment.

PATIENTS AND METHODS

Fifty-eight Japanese patients, including 15 with HTLV-1-associated bronchiolitis and 43 with diffuse panbronchiolitis. Both conditions were clinically compared using the clinical criteria for diffuse panbronchiolitis, including findings from CT scans and BAL fluid testing. Pulmonary function, blood gas levels, and cold hemagglutinin (CHA) levels were assessed before and after long-term treatment with macrolides. Interleukin-2 receptor (IL-2R) expression in T cells obtained from the BAL fluid of patients with HTLV-1-associated bronchiolitis or diffuse panbronchiolitis was analyzed by flow cytometry.

RESULTS

Clinical, laboratory, radiologic, and bacterial features were strikingly similar in both groups, except for the fact that patients with HTLV-1-associated bronchiolitis had a higher ratio of IL-2R-positive cells in the BAL fluid. The histopathologic features were also similar. Long-term treatment with macrolides improved PaO(2), FEV(1), and CHA in patients with HTLV-1-associated bronchiolitis to a lesser extent than in those with diffuse panbronchiolitis, and PaO(2) and FEV(1) in the group of patients with HTLV-1-associated bronchiolitis who had high IL-2R levels did not respond after therapy.

CONCLUSIONS

These findings showed that the clinicopathologic features of the two conditions are quite similar, suggesting that diffuse panbronchiolitis is a chronic pulmonary manifestation of HTLV-1 infection. However, HTLV-1-associated bronchiolitis might be associated with conditions that are distinct from those of diffuse panbronchiolitis based on the different responses to macrolide treatment and the difference in the number of activated T cells bearing IL-2R in the lungs.

Immunomodulatory activity and effectiveness of macrolides in chronic airway disease

The use of troleandomycin as adjunctive therapy for the treatment of patients with corticosteroid-dependent asthma first suggested an immunomodulatory effect of the macrolide antibiotics. This led to studies of the macrolides in other chronic airway diseases, such as diffuse panbronchiolitis (DPB), a disease occurring primarily in East Asia. The use of macrolides for the therapy of patients with DPB has led to dramatic improvements in pulmonary function and prolonged survival. Similar benefits have been documented in Japanese studies of bronchiectasis, chronic bronchitis, and sinobronchial syndrome. Clinical and pathologic similarities between DPB and cystic fibrosis (CF) led to the investigation of macrolides for the treatment of CF. Data now suggest that persons with CF will benefit from macrolide therapy. In vitro and in vivo studies suggest that macrolides may inhibit the pulmonary influx of neutrophils, inhibit the release of proinflammatory cytokines, protect the epithelium from bioactive phospholipids, and improve the transportability of airway secretions. The immunomodulatory effects of the macrolides also may be beneficial for the treatment of other chronic inflammatory conditions.

Bronchiolar disorders

Bronchiolar abnormalities are relatively common and occur in a variety of clinical settings. Various histopathologic patterns of bronchiolar injury have been described and have led to confusing nomenclature with redundant and overlapping terms. Some histopathologic patterns of bronchiolar disease may be relatively unique to a specific clinical context but others are nonspecific with respect to either etiology or pathogenesis. Herein, we present a scheme separating (1) those disorders in which the bronchiolar disease is the predominant abnormality (primary bronchiolar disorders) from (2) parenchymal disorders with prominent bronchiolar involvement and (3) bronchiolar involvement in large airway diseases. Primary bronchiolar disorders include constrictive bronchiolitis (obliterative bronchiolitis, bronchiolitis obliterans), acute bronchiolitis, diffuse panbronchiolitis, respiratory bronchiolitis, mineral dust airway disease, follicular bronchiolitis, and a few other rare variants. Prominent bronchiolar involvement may be seen in several interstitial lung diseases, including hypersensitivity pneumonitis, respiratory bronchiolitis-associated interstitial lung disease, cryptogenic organizing pneumonia (idiopathic bronchiolitis obliterans organizing pneumonia), and pulmonary Langerhans' cell histiocytosis. Large airway diseases that commonly involve bronchioles include bronchiectasis, asthma, and chronic obstructive pulmonary disease. The clinical relevance of a bronchiolar lesion is best determined by identifying the underlying histopathologic pattern and assessing the correlative clinico-physiologic-radiologic context.

Increased macrophage inflammatory protein-1alpha and -1beta in BAL fluid of bronchiolitis obliterans organizing pneumonia

OBJECTIVE

CC chemokines are mainly chemotactic for monocytes and lymphocytes. The aim of this study was to evaluate the involvement of the CC chemokines, macrophage inflammatory protein (MIP)-1alpha and MIP-1beta, in the pathogenesis of bronchiolitis obliterans organizing pneumonia (BOOP).

METHODOLOGY

The concentrations of MIP-1alpha and MIP-1beta in BAL fluid (BALF) obtained from patients with BOOP (n = 13) and control patients (CP, n= 18) were measured by enzyme-linked immunosorbent assay.

RESULTS

MIP-1alpha in BALF was significantly higher in patients with BOOP (mean +/- SD; 123.8 +/- 98.0 pg/mL) than in CP (62.5 +/- 46.1 pg/mL). Significantly higher MIP-1beta was also detected in patients with BOOP (51.6 +/- 72.5 pg/mL) than in CP (6.4 +/- 3.7 pg/mL). The concentration of MIP-1alpha significantly correlated with the percentage of lymphocytes in BALF, and the concentration of MIP-1beta significantly correlated with the numbers of lymphocytes, neutrophils and eosinophils in BALF. Both MIP-1alpha and MIP-1beta in BALF were decreased after corticosteroid therapy and this was accompanied by decreased lymphocytes in BALF.

CONCLUSION

This study suggests that MIP-1alpha and MIP-1beta may play important roles in the recruitment of immuno-inflammatory cells into the lungs, and may contribute to the pathogenesis of BOOP.

Increased concentrations of human beta-defensins in plasma and bronchoalveolar lavage fluid of patients with diffuse panbronchiolitis

BACKGROUND

Human beta-defensin (HBD)-1 and -2 are antimicrobial peptides present in the respiratory tract. Recent reports have indicated reduced activity of beta-defensins in cystic fibrosis, suggesting that beta-defensins may play an important role in the pathological process of chronic respiratory tract infection. Diffuse panbronchiolitis (DPB) is a progressive disease characterised by frequent episodes of superimposed infection, typically caused by Pseudomonas aeruginosa. The aim of this study was to elucidate the role of these antimicrobial peptides in this disease.

METHODS

The concentrations of HBD-1 and HBD-2 in plasma and bronchoalveolar lavage (BAL) fluid from 33 patients with DPB and 30 normal adults were measured by radioimmunoassay. Localisation of HBD-2 was investigated immunohistochemically in an open lung biopsy specimen obtained from a patient with DPB.

RESULTS

High concentrations of HBD-1 and HBD-2 were noted in BAL fluid from DPB patients. Increased plasma concentrations of HBD-2, but not HBD-1, were found in patients with DPB compared with control subjects. In patients with DPB the HBD-2 concentration in BAL fluid correlated significantly with the numbers of cells recovered from the BAL fluid (total cells, neutrophils, and lymphocytes) and with the BAL fluid concentration of IL-1beta. Synthetic HBD-2, but not HBD-1, had dose dependent bactericidal activity against P aeruginosa. Treatment of 14 patients with macrolides significantly reduced BAL fluid concentrations of HBD-2 but not HBD-1 or plasma concentrations of HBD-1 and HBD-2. Immunohistochemistry of lung tissue showed localisation of HBD-2 in the epithelia of the distal bronchioles.

CONCLUSIONS

These results indicate that beta-defensins, particularly HBD-2, participate in antimicrobial defence in the respiratory tract in DPB, and that the BAL fluid concentration of HBD-2 may be a useful marker of airway inflammation in patients with DPB.