Co-localization of iron binding on silica with p62/sequestosome1 (SQSTM1) in lung granulomas of mice with acute silicosis.

The cellular mechanisms involved in the development of silicosis have not been fully elucidated. This study aimed to examine influence of silica-induced lung injury on autophagy. Suspensions of crystalline silica particles were administered transnasally to C57BL/6j mice. Immunohistochemical examination for Fas and p62 protein expression was performed using lung tissue specimens. Two-dimensional and quantitative analysis of silica deposits in the lungs were performed in situ using lung tissue sections by an in-air microparticle induced X-ray emission (in-air micro-PIXE) analysis system, which was based on irrradiation of specimens with a proton ion microbeam. Quantitative analysis showed a significant increase of iron levels on silica particles (assessed as the ratio of Fe relative to Si) on day 56 compared with day 7 (p<0.05). Fas and p62 were expressed by histiocytes in granulomas on day 7, and the expressions persisted for day 56. Fas- and p62-expressing histiocytes were co-localized in granulomas with silica particles that showed an increase of iron levels on silica particles in mouse lungs. Iron complexed with silica induces apoptosis, and may lead to dysregulations of autophagy in histiocytes of granulomas, and these mechanisms may contribute to granuloma development and progression in silicosis.

Safety and efficacy of high-dose leukocytapheresis in patients with refractory asthma.

OBJECTIVE AND DESIGN: An open-label, non-randomized, single-arm study was performed to investigate the safety and efficacy of high-dose leukocytapheresis (pulse LCAP) for refractory asthma. SUBJECTS: Six patients who fulfilled the ATS workshop criteria for refractory asthma were enrolled and completed this clinical study. TREATMENT: After 4 weeks of observation, pulse LCAP using a large LCAP filter, Cellsorba(®) CS-180S, was performed twice with a 1-week interval at a target dose of 5 L per treatment session. METHODS: The clinical response was assessed by monitoring the peak expiratory flow rate (PEFR) twice a day. The asthma control test (ACT) was used to evaluate the condition of asthma symptoms. The fraction of exhaled nitric oxide (FeNO) as a biomarker for eosinophilic airway inflammation was measured using a chemiluminescence analyzer. RESULTS: PEFR in the morning or the evening and the sum total of the score on the ACT were increased after two consecutive sessions of pulse LCAP. FeNO decreased after pulse LCAP. CONCLUSIONS: The results suggest the efficacy of pulse LCAP for refractory asthma.

Lysophosphatidic acid inhibits CC chemokine ligand 5/RANTES production by blocking IRF-1-mediated gene transcription in human bronchial epithelial cells.

Lysophosphatidic acid (LPA) is a phospholipid mediator that exerts a variety of biological responses through specific G-protein-coupled receptors (LPA(1)-LPA(5) and P2Y5). LPA is thought to be involved in airway inflammation by regulating the expression of anti-inflammatory and proinflammatory genes. Chemokines such as CCL5/RANTES are secreted from airway epithelium and play a key role in allergic airway inflammation. CCL5/RANTES is a chemoattractant for eosinophils, T lymphocytes, and monocytes and seems to exacerbate asthma. We stimulated CCL5/RANTES production in a human bronchial epithelial cell line, BEAS-2B, with IFN-γ and TNF-α. When LPA was added, CCL5/RANTES mRNA expression and protein secretion were inhibited, despite the presence of IFN-γ and TNF-α. The LPA effect was attenuated by Ki16425, a LPA(1)/LPA(3) antagonist, but not by dioctylglycerol pyrophosphate 8:0, an LPA(3) antagonist. Pertussis toxin, the inhibitors for PI3K and Akt also attenuated the inhibitory effect of LPA on CCL5/RANTES secretion. We also identify the transcription factor IFN regulatory factor-1 (IRF-1) as being essential for CCL5/RANTES production. Interestingly, LPA inhibited IFN-γ and TNF-α-induced IRF-1 activation by blocking the binding of IRF-1 to its DNA consensus sequence without changing IRF-1 induction and its nuclear translocation. Ki16425, pertussis toxin, and PI3K inhibitors attenuated the inhibitory effect of LPA on IRF-1 activation. Our results suggest that LPA inhibits IFN-γ- and TNF-α-induced CCL5/RANTES production in BEAS-2B cells by blocking the binding of IRF-1 to the CCL5/RANTES promoter. LPA(1) coupled to G(i) and activation of PI3K is required for this unique effect.

COVID-19 mRNA Vaccine-induced Pneumonitis.

A 65-year-old man experienced cough and shortness of breath 3 days after receiving the first dose of the Pfizer-BioNTech coronavirus disease 2019 (COVID-19) vaccine. Chest X-ray revealed bilateral infiltrates, and the desaturation deteriorated rapidly. The symptoms and radiographic abnormalities rapidly improved after the initiation of corticosteroid therapy. Intradermal testing of the Pfizer-BioNTech COVID-19 vaccine showed a delayed positive reaction. Based on these findings, the patient was diagnosed with COVID-19 vaccine-induced pneumonitis. The timing of the onset of pneumonitis after vaccination and the results of intradermal testing suggest that Type IV hypersensitivity against COVID-19 vaccine may have been responsible for this clinical condition.

Extracellular acidification induces connective tissue growth factor production through proton-sensing receptor OGR1 in human airway smooth muscle cells.

Asthma is characterized by airway inflammation, hyper-responsiveness and remodeling. Extracellular acidification is known to be associated with severe asthma; however, the role of extracellular acidification in airway remodeling remains elusive. In the present study, the effects of acidification on the expression of connective tissue growth factor (CTGF), a critical factor involved in the formation of extracellular matrix proteins and hence airway remodeling, were examined in human airway smooth muscle cells (ASMCs). Acidic pH alone induced a substantial production of CTGF, and enhanced transforming growth factor (TGF)-ß-induced CTGF mRNA and protein expression. The extracellular acidic pH-induced effects were inhibited by knockdown of a proton-sensing ovarian cancer G-protein-coupled receptor (OGR1) with its specific small interfering RNA and by addition of the G(q/11) protein-specific inhibitor, YM-254890, or the inositol-1,4,5-trisphosphate (IP(3)) receptor antagonist, 2-APB. In conclusion, extracellular acidification induces CTGF production through the OGR1/G(q/11) protein and inositol-1,4,5-trisphosphate-induced Ca(2+) mobilization in human ASMCs.

Elemental analysis of lung tissue particles and intracellular iron content of alveolar macrophages in pulmonary alveolar proteinosis.

BACKGROUND: Pulmonary alveolar proteinosis (PAP) is a rare disease occurred by idiopathic (autoimmune) or secondary to particle inhalation. The in-air microparticle induced X-ray emission (in-air micro-PIXE) system performs elemental analysis of materials by irradiation with a proton microbeam, and allows visualization of the spatial distribution and quantitation of various elements with very low background noise. The aim of this study was to assess the secondary PAP due to inhalation of harmful particles by employing in-air micro-PIXE analysis for particles and intracellular iron in parafin-embedded lung tissue specimens obtained from a PAP patient comparing with normal lung tissue from a non-PAP patient. The iron inside alveolar macrophages was stained with Berlin blue, and its distribution was compared with that on micro-PIXE images. RESULTS: The elements composing particles and their locations in the PAP specimens could be identified by in-air micro-PIXE analysis, with magnesium (Mg), aluminum (Al), silicon (Si), phosphorus (P), sulfur (S), scandium (Sc), potassium (K), calcium (Ca), titanium (Ti), chromium (Cr), copper (Cu), manganase (Mn), iron (Fe), and zinc (Zn) being detected. Si was the major component of the particles. Serial sections stained by Berlin blue revealed accumulation of sideromacrophages that had phagocytosed the particles. The intracellular iron content of alveolar macrophage from the surfactant-rich area in PAP was higher than normal lung tissue in control lung by both in-air micro-PIXE analysis and Berlin blue staining. CONCLUSION: The present study demonstrated the efficacy of in-air micro-PIXE for analyzing the distribution and composition of lung particles. The intracellular iron content of single cells was determined by simultaneous two-dimensional and elemental analysis of paraffin-embedded lung tissue sections. The results suggest that secondary PAP is associated with exposure to inhaled particles and accumulation of iron in alveolar macrophages.

PI3K p110beta positively regulates lipopolysaccharide-induced IL-12 production in human macrophages and dendritic cells and JNK1 plays a novel role.

The PI3K family is thought to participate in TLR signaling, and it has been reported to be a negative regulator of TLR-mediated production of IL-12, a key inducer of Th1 responses. However, the role of individual PI3K subtypes in IL-12 production remains obscure. We defined the distinct regulation of LPS-mediated IL-12 production by p110alpha and p110beta catalytic subunits of PI3K in human APCs. We observed that knockdown of PI3K p110beta by small interfering RNA (siRNA) suppressed both LPS-induced IL-12 protein production and mRNA expression in monocyte-derived macrophages and dendritic cells (DCs). Knockdown of PI3K p110alpha by siRNA reduced LPS-induced IL-12 protein production in both cell types. Conversely, knockdown of PI3K p110alpha suppressed LPS-induced IL-12 mRNA expression in monocyte-derived macrophages but minimally affected monocyte-derived DCs. PI3K p110beta siRNA inhibited JNK activation, but not p38 MAPK or ERK activation, stimulated by LPS, while PI3K p110alpha siRNA did not affect LPS-induced JNK, p38 MAPK, or ERK activation in both cell types. Transfection of siRNA against JNK1, JNK2, and both decreased LPS-induced IL-12 production. Furthermore, PI3K p110beta siRNA attenuated LPS-induced JNK1 phosphorylation, while not affecting JNK2 phosphorylation. Our findings indicate that PI3K p110beta positively controls LPS-induced IL-12 production through the JNK1-dependent pathway in human macrophages and DCs.

Prevalence of asthma symptoms based on the European Community Respiratory Health Survey questionnaire and FENO in university students: gender differences in symptoms and FENO.

BACKGROUND: The fractional concentration of nitric oxide in exhaled air (FENO) is used as a biomarker of eosinophilic airway inflammation. FENO is increased in patients with asthma. The relationship between subjective asthma symptoms and airway inflammation is an important issue. We expected that the subjective asthma symptoms in women might be different from those in men. Therefore, we investigated the gender differences of asthma symptoms and FENO in a survey of asthma prevalence in university students. METHODS: The information about asthma symptoms was obtained from answers to the European Community Respiratory Health Survey (ECRHS) questionnaire, and FENO was measured by an offline method in 640 students who were informed of this study and consented to participate. RESULTS: The prevalence of asthma symptoms on the basis of data obtained from 584 students (266 men and 318 women), ranging in age from 18 to 24 years, was analyzed. Wheeze, chest tightness, an attack of shortness of breath, or an attack of cough within the last year was observed in 13.2% of 584 students. When 38.0 ppb was used as the cut-off value of FENO to make the diagnosis of asthma, the sensitivity was 86.8% and the specificity was 74.0%. FENO was ≥ 38.0 ppb in 32.7% of students. FENO was higher in men than in women. The prevalence of asthma symptoms estimated by considering FENO was 7.2%; the prevalence was greater in men (9.4%) than women (5.3%). A FENO ≥ 38.0 ppb was common in students who reported wheeze, but not in students, especially women, who reported cough attacks. CONCLUSIONS: The prevalence of asthma symptoms in university students age 18 to 24 years in Japan was estimated to be 7.2% on the basis of FENO levels as well as subjective symptoms. Gender differences were observed in both FENO levels and asthma symptoms reflecting the presence of eosinophilic airway inflammation. TRIAL REGISTRATION NUMBER: UMIN000003244.

JNK1 and JNK2 differently regulate IL-12 production in THP-1 macrophage cells.

Macrophages play a key role in initiating the innate responses to infection by secreting cytokines such as interleukin-12 (IL-12). This study defined the distinct regulation of lipopolysaccharide (LPS)-mediated IL-12 production by c-jun NH(2)-terminal kinase (JNK)1 and JNK2 isoforms in human macrophages. Knockdown of JNK1 and JNK2 by small interference RNA (siRNA) reduced and enhanced LPS-induced IL-12 p40 production in THP-1 macrophage cells, respectively. The simultaneous knockdown of JNK1 and JNK2 augmented LPS-induced IL-12 production as well as a specific JNK inhibitor. In addition, transfection of siRNA against phosphoinositide 3-kinase (PI3K) p110beta attenuated LPS-induced IL-12 production and JNK1 phosphorylation, while not affecting JNK2 phosphorylation. These findings indicate that JNK1- and JNK2-mediated signaling plays a positive and a negative role, respectively, in LPS-induced IL-12 production and PI3K p110beta controls LPS-induced JNK1 activation, not JNK2 activation, resulting in the positive regulation of IL-12 production in THP-1 macrophage cells.

Primary Sjogren's syndrome complicated by bilateral pleural effusion.

Sjogren's syndrome can cause many organic changes, but is rarely accompanied by pleuritis. We report a 65-year-old patient with primary Sjogren's syndrome who developed bilateral pleuritis with moderately large effusions. He was diagnosed as having Sjogren's syndrome, based on xerophthalmia, xerostomia, positive results for anti-Sjogren's syndrome (anti-SS-A/SS-B) antibodies, the Schirmer test and biopsy findings in the minor salivary glands. The pleural fluid was lymphocyte rich and contained high levels of anti-SS-A/SS-B antibodies. There was no evidence of infection, malignancy or other collagen diseases which cause pleuritis. We conclude that this case adds to the eight previously published reports of primary Sjogren's syndrome complicated by pleural effusion.

In-air microparticle induced X-ray emission analysis of particles in interstitial pneumonia lung tissue obtained by transbronchial biopsy.

Interstitial pneumonia develops in association with inhaled particles. In-air microparticle induced X-ray emission (in-air micro) analysis was previously employed to assess the spatial distribution and content of particles in surgical lung biopsy specimens. The aim of this study was to assess the efficacy of in-air micro-analysis for transbronchial lung biopsy specimens in patients with or without occupational exposure. The elements composing lung particles and their locations could be identified by in-air micro-analysis. Silicon was the major component of particles. Quantitative analysis revealed that the elements composing lung particles varied between patients. In a patient with suspected nickel exposure, aluminium, vanadium, and calcium were detected, but was not detected. In a patient without a work history (housewife), various elements were detected. In-air micro-analysis was useful for assessing the spatial distribution and content of particles in specimens from patients. Occupational exposure was not necessarily associated with deposition of particles in the lungs. Therefore, in the diagnosis of, elemental analysis of specimens by in-air micro-analysis could be useful for assessing exposure to particles objectively.