An Interleukin-33-Mast Cell-Interleukin-2 Axis Suppresses Papain-Induced Allergic Inflammation by Promoting Regulatory T Cell Numbers.

House dust mite-derived proteases contribute to allergic disorders in part by disrupting epithelial barrier function. Interleukin-33 (IL-33), produced by lung cells after exposure to protease allergens, can induce innate-type airway eosinophilia by activating natural helper (NH) cells, a member of group 2 innate lymphoid cells (ILC2), to secrete Th2 type-cytokines. Because IL-33 also can induce mast cells (MCs) to secrete Th2 type-cytokines, MCs are thought to cooperate with NH cells in enhancing protease or IL-33-mediated innate-type airway eosinophilia. However, we found that MC-deficient Kit(W-sh/W-sh) mice exhibited exacerbated protease-induced lung inflammation associated with reduced numbers of regulatory T (Treg) cells. Moreover, IL-2 produced by IL-33-stimulated MCs promoted expansion of numbers of Treg cells, thereby suppressing development of papain- or IL-33-induced airway eosinophilia. We have thus identified a unique anti-inflammatory pathway that can limit induction of innate-type allergic airway inflammation mediated by NH cells.

Prolonged SARS-CoV-2 infection associated with long-term corticosteroid use in a patient with impaired B-cell immunity.

Corticosteroids are widely used to treat severe COVID-19, but in immunocompromised individuals, who are susceptible to persistent infection, long term corticosteroid use may delay viral clearance. We present a case of prolonged SARS-CoV-2 infection in a man with significantly impaired B-cell immunity due to non-Hodgkin lymphoma which had been treated with rituximab. SARS-CoV-2 shedding persisted, despite treatment with remdesivir. Viral sequencing confirmed the persistence of the same viral strain, ruling out the possibility of reinfection. Although SARS-CoV-2 IgG, IgA and IgM remained negative throughout the treatment period, after reduction of the corticosteroid dose, PCR became negative. Long-term corticosteroid treatment, especially in immunocompromised individuals, may result in suppression of cell-mediated immunity and prolonged SARS-CoV-2 infection.

Mechanism of Periostin Production in Human Bronchial Smooth Muscle Cells.

BACKGROUND: Asthma is a chronic airway inflammatory disease characterized by airway remodeling, in which the bronchial smooth muscle (BSM) cells play an important role. Periostin, a biomarker that reflects Th2-driven inflammatory diseases such as asthma, may play an important role in the asthmatic airway. Although periostin is mainly produced in airway epithelial cells and fibroblasts after interleukin (IL)-13 stimulation, whether BSM cells produce periostin remains unclear. Therefore, we investigated periostin production in BSM cells and the mechanisms involved. METHODS: Human BSM cells were cultured, and the effect of IL-13 stimulation on periostin production was evaluated using quantitative polymerase chain reaction and enzyme-linked immunosorbent assay (ELISA). We evaluated the phosphorylation of signal transducer and activator of transcription factor 6 (STAT6), extracellular signal-regulated kinase (ERK)1/2, and Akt after IL-13 stimulation. Furthermore, using ELISA, we evaluated the influence of several phosphorylation inhibitors on periostin production. RESULTS: Periostin mRNA expression increased in a dose- and time-dependent manner after IL-13 stimulation; periostin production was induced 24 and 48 h after stimulation. IL-13 stimulation induced the phosphorylation of STAT6, ERK1/2, and Akt. IL-13-induced periostin production was attenuated by inhibiting STAT6 phosphorylation and strongly suppressed by inhibiting mitogen-activated protein kinase kinase 1/2 phosphorylation or phosphatidylinositol 3-kinase (PI3K) phosphorylation. CONCLUSIONS: BSM cells produced periostin after IL-13 stimulation, via the JAK/STAT6, ERK1/2, and PI3K/Akt pathways. Understanding the mechanism of periostin production in BSM cells may help to clarify asthma pathogenesis.

Sensitivity and specificity of QuantiFERON-TB Gold Plus compared with QuantiFERON-TB Gold In-Tube and T-SPOT.TB on active tuberculosis in Japan.

BACKGROUND: The QuantiFERON-TB Gold Plus (QFT-Plus) was introduced in 2015 as a new generation of interferon-gamma release assays (IGRAs) designed to detect Mycobacterium tuberculosis infection (TB). Examination of its diagnostic accuracy is crucial before it is launched in Japan. METHOD: We examined 99 patients with laboratory-confirmed active TB (patients) and 117 healthy volunteers with no risk of TB infection (controls) at a medical center in Tokyo, Japan. Blood samples were collected from both the patients and controls and tested using three types of IGRAs: the QFT-Plus, the QuantiFERON-TB Gold In-Tube (QFT-GIT), and the T-SPOT.TB (T-SPOT). The sensitivity and specificity of each IGRA were examined and compared. RESULTS: The sensitivity of the QFT-Plus was 98.9% (95% confidence interval [CI], 0.934-0.998) and similar to that of the QFT-GIT (97.9%; 95% CI, 0.929-0.998) and T-SPOT (96.9%; 95% CI, 0.914-0.994). The specificity of the QFT-Plus was the same as that of the QFT-GIT and T-SPOT (98.1%; 95% CI, 0.934-0.998). One patient with uncontrolled diabetes mellitus showed negative results on all three IGRAs. CONCLUSIONS: The QFT-Plus showed a high degree of agreement with the QFT-GIT and T-SPOT, with high sensitivity and specificity. Severe diabetes mellitus may influence the results of IGRAs. Larger studies are needed to validate the accuracy of the GFT-Plus and determine whether it can contribute as adjunctive method for the early diagnosis of active TB in Japan.

Effectiveness of clarithromycin in patients with yellow nail syndrome.

BACKGROUND: Yellow nail syndrome (YNS) is a rare disease characterized by the triad of thickened, slow-growing yellow nails, lymphedema, and chronic respiratory manifestations. The cause of YNS is not known; however, it is suggested to be due to a congenital lymph abnormality. Since YNS is accompanied by chronic bronchial infection in more than half of patients, we hypothesized that treatment with clarithromycin (CAM) could be effective. We therefore evaluated the effectiveness of CAM against nail discoloration and respiratory manifestation in patients with YNS. METHODS: We conducted an observational study involving 5 patients with YNS who were treated at our institution between January 2005 and January 2016. CAM was prescribed for every patient. Patient demographic information, comorbidities, medications, chest radiographs, and clinical data such as nail color were extracted to evaluate clinical outcome. RESULTS: Mean patient age was 71.6 years, and 2 patients (40%) were male. Four patients had sinusitis, and 2 had rheumatoid arthritis. Regarding respiratory manifestations, 4 patients had sinobronchial syndrome and 2 had pleural effusion. Nail discoloration improved in every patient after CAM treatment. Four patients also experienced improvement in their respiratory manifestations. CONCLUSIONS: In patients with YNS, the anti-inflammatory activity of macrolides might improve their systemic inflammation. This improvement could help to reduce lymphedema and promote nail growth. TRIAL REGISTRATION: Ethical approval was provided by the institutional review board of the National Center of Global Health and Medicine (NCGM-G-002143-00), in January 2017. This study is retrospectively registered for UMIN Clinical Trial Registry ( UMIN000028514 ) in August 4th, 2017.

Comparison of the clinical effects of combined salmeterol/fluticasone delivered by dry powder or pressurized metered dose inhaler.

The salmeterol/fluticasone combination (SFC) inhaler is currently the most widely used maintenance drug for asthmatics worldwide. Although the effectiveness of SFC as either a dry powder inhaler (DPI) or a pressurized metered dose inhaler (pMDI) is well documented, there is limited data comparing the clinical efficacies of the two devices. To address this issue, we carried out a randomized crossover trial in which asthmatic patients (n = 47; mean age, 62.5 ± 16.5 years old) received a 12-week treatment of SFC DPI (50/250 µg twice daily) or SFC pMDI (four puffs of 25/125 µg daily). After a 4-week washout period, patients received another crossover treatment for 12 weeks. Respiratory resistance and reactance were measured by forced oscillation technique (MostGraph-01), spirometry, fractional exhaled nitric oxide (FeNO), and an asthma control test (ACT) every 4 weeks. The mean forced expiratory volume1.0 at the baseline was 2.16 ± 0.86 (L). Respiratory system resistance at 5 Hz (R5), the difference between R5 and R at 20 Hz (R5 - R20), and FeNO improved in both treatment groups, while reactance at 5 Hz (X5) and ACT score improved only in the pMDI group. In patients >70 years old (n = 21), R5, R5 - R20, ΔX5, and FeNO improved only in the pMDI group. These results suggest that SFC by pMDI produces a stronger anti-inflammatory and bronchodilatory effect even in patients whose asthma is well controlled by SFC delivered by DPI.

TIM-3 is not essential for development of airway inflammation induced by house dust mite antigens.

BACKGROUND: T cell immunoglobulin domain and mucin domain-containing molecule 3 (TIM-3), which is preferentially expressed on Th1 cells rather than Th2 cells, is considered to be a negative regulator of Th1 cell function. This suggests that TIM-3 indirectly enhances Th2-type immune responses by suppressing Th1 cell function. METHODS: To investigate TIM-3's possible involvement in Th2-type acute and chronic airway inflammation, wild-type and TIM-3-deficient (TIM-3-/-) mice were sensitized and challenged with a house dust mite (HDM) extract. Airway inflammation and the number of inflammatory cells in bronchoalveolar lavage fluids (BALFs) in the mice were determined by histological analysis and with a hemocytometer, respectively. Expression of mRNA in the lungs was determined by quantitative PCR, while the levels of cytokines in the BALFs and IgE in sera were determined by ELISA. RESULTS: Despite constitutive expression of TIM-3 mRNA in the lungs, the number of eosinophils in bronchoalveolar lavage fluids (BALFs) and the score of pulmonary inflammation were comparable between wild-type and TIM-3-/- mice during both acute and chronic HDM-induced airway inflammation. On the other hand, the number of lymphocytes in the BALFs of TIM-3-/- mice was significantly increased compared with wild-type mice during HDM-induced chronic, but not acute, airway inflammation, while the levels of Th2 cytokines in the BALFs and HDM-specific IgG1 and IgG2a and total IgE in the sera were comparable in both groups. CONCLUSIONS: Our findings indicate that, in mice, TIM-3 is not essential for development of HDM-induced acute or chronic allergic airway inflammation, although it appears to be involved in reduced lymphocyte recruitment during HDM-induced chronic allergic airway inflammation.

The impact of co-existing seasonal allergic rhinitis caused by Japanese Cedar Pollinosis (SAR-JCP) upon asthma control status.

BACKGROUND: Seasonal Allergic Rhinitis Caused by Japanese Cedar Pollinosis (SAR-JCP) is a most common allergic rhinitis, affecting about 40% in Japan, but the influence from SAR-JCP upon asthma is controversial. The purpose of this study is to investigate the effect of coexistence of SAR-JCP upon control status of asthma using SACRA (Self-Assessment of Allergic Rhinitis and Asthma Questionnaire). METHODS: The design was prospective, single-center, observational study. Asthmatic patients were classified into 3 groups, patients without rhinitis, those with perennial rhinitis or those with SAR-JCP from the results of SACRA. The control status of asthma were evaluated by Visual Analog Scale (VAS) in SACRA and Asthma Control Test (ACT) score. They were evaluated twice, from September to January (nonpollen-season) and February to April (pollen-season) and compared. RESULTS: 451 patients were enrolled and 325 cases (72%) were diagnosed as having comorbidity of rhinitis, among which 173 with only perennial rhinitis, while 152 with SAR-JCP. There was no significant difference in asthma control level measured by VAS and ACT score among 3 groups during nonpollen-season. The asthma control level measured by VAS (1.91-2.95) and ACT score (22.7-21.6) got worse during pollen-season among patients with SAR-JCP, even though 84% received treatment for rhinitis. Although it differed according to criteria, asthma control during pollen-season was impaired in 18-38% asthmatic patients with SAR-JCP. CONCLUSION: It is possible to minimize the influence of AR on asthma control by obtaining an accurate diagnosis and providing sufficient treatment for rhinitis.

A comparison of long-term anti-inflammatory effect of two ICS/LABA combination inhalers; fix-dosed maintenance therapy with budesonide/formoterol and salmeterol/fluticasone.

BACKGROUND: The clinical usefulness of fixed-dose maintenance therapy with salmeterol/fluticasone (SFC) and budesonide/formoterol combination inhaler (BUD/FM) has been established, though evidence of the long-term anti-inflammatory effects of these 2 inhalers are limited. METHODS: Patients with moderate persistent adult asthma who had received SFC 50/250µg bid with well-control status were recruited. After switching to 8-week therapy with fixed-dose BUD/FM 4 puffs (640/18µg) (phase-1), patients chose either SFC or BUD/FM. FeNO and ACT score were evaluated every 8 weeks until the end of the 52-week treatment period for both treatment groups (phase-2). RESULTS: In total, 103 patients were examined: BUD/FM was chosen by 34 patients (BUD/FM group), while SFC was chosen by 23 (SFC group). Thirty-six received SFC consistently from the beginning of the study (control). Patients in the BUD/FM and SFC groups showed significant improvements in ACT scores and FeNO levels in phase-1; these beneficial effects persisted for 52 weeks in the BUD/FM group. On the other hand, in the SFC group, although the FeNO level decreased from 54.3 ± 26.4 ppb to 41.9 ± 18.3 ppb in phase-1, it increased to 54.5 ± 26.2 ppb, a level similar to the baseline prior to the beginning of BUD/FM therapy, at 8 weeks in phase-2, and remained at 50-odd ppb thereafter. CONCLUSIONS: These results suggest that maintenance therapy with fixed-dose BUD/FM is a useful treatment option exerting an airway anti-inflammatory effect for a period as long as 1 year, even for asthmatics who could not accomplish total control with SFC.

Clinical usefulness of a guideline-based screening tool for the diagnosis of allergic rhinitis in asthmatics: the Self Assessment of Allergic Rhinitis and Asthma questionnaire.

BACKGROUND AND OBJECTIVE: Allergic rhinitis (AR) is common in asthmatic patients and may impair asthma control. However, this comorbidity is frequently missed. A simple test is needed to enable physicians to diagnose and evaluate the severity of both diseases. The Self Assessment of Allergic Rhinitis and Asthma (SACRA) questionnaire, which GINA and ARIA Japan committees developed in 2011, consist of questionnaires based on GINA and ARIA guidelines for the diagnosis and severity of AR and asthma, and a visual analogue scale (VAS) to evaluate the severity of both diseases. Our objective was to investigate the clinical usefulness of SACRA as a patient-based screening tool for identifying asthmatic patients with AR. METHODS: SACRA, ACT (Asthma Control Test) and serum IgE RAST were performed in asthmatic patients. The correlation between SACRA and other parameters were analyzed. RESULTS: Four hundred twenty asthmatic patients were enrolled. Among 168 subjects who self-reported no concomitant AR, 76 asthmatics scored one or more symptoms on SACRA. Eventually, 32 of these 76 subjects were diagnosed with AR by physicians based on laboratory data or physical examinations by ear, nose and throat specialists. The sensitivity and specificity of SACRA for the diagnosis of AR were 92% and 66%, respectively. The estimated prevalence of AR among asthmatics was 66%, almost identical to that of the previous nationwide study in Japan. The level of asthma control assessed by the VAS on SACRA and the ACT score showed a strong correlation (r = -0.700, P < 0.001). CONCLUSIONS: SACRA may be a clinically useful tool for identifying bronchial asthma patients with AR.

Asthma control can be maintained after fixed-dose, budesonide/ formoterol combination inhaler therapy is stepped down from medium to low dose.

BACKGROUND: In cases using a budesonide/formoterol combination inhaler, many patients are started on fixed-dose treatment at 640/18µg (4 puffs) daily, but there are no guidelines yet regarding the step-down method when control has been maintained. METHODS: Patients with moderate asthma treated with either budesonide 400µg and salmeterol 100µg (GINA step3 group) or salmeterol/fluticasone 250 at 2 puffs (GINA step4 group) were enrolled and started on therapy of budesonide/formoterol 4 puffs. Thereafter, step-down to 2 puffs was performed if either of the following criteria was met at 8-week intervals: fractional exhaled nitric oxide (FeNO) ≤ 28 ppb plus asthma control test (ACT) score ≥ 22, or ACT score ≥ 24 at 3 consecutive visits regardless of FeNO level. Thereafter, changes in ACT score, the number of acute exacerbations and reliever use, and FeNO level were monitored through 48th week. RESULTS: Fifty-one patients, 27 in step3 group and 24 in step4 group, underwent step-down. ACT scores and the number of reliever use remained stable in both groups even after step-down. In contrast, FeNO levels increased gradually in step4 group, whereas in the step3 group they increased immediately after step-down. Step-down was considered to be safely performed because the numbers of reliever use and those of moderate or more severe exacerbations during the 48-week period has not changed significantly compared to before step-down. CONCLUSIONS: If complete control of asthma, not only of clinical symptoms but also airway inflammation, is achieved by 3-6 months of fixed-dose budesonide/formoterol 4 puffs/day, it should be possible to safely perform step-down to 2 puffs/day.

Asthma Control Can Be Maintained after Fixed-Dose, Budesonide/Formoterol Combination Inhaler Therapy is Stepped Down from Medium to Low Dose.

BACKGROUND: In cases using a budesonide/formoterol combination inhaler, many patients are started on fixed-dose treatment at 640/18 µg (4 puffs) daily, but there are no guidelines yet regarding the step-down method when control has been maintained. METHODS: Patients with moderate asthma treated with either budesonide 400 µg and salmeterol 100 µg (GINA step3 group) or salmeterol/fluticasone 250 at 2 puffs (GINA step4 group) were enrolled and started on therapy of budesonide/formoterol 4 puffs. Thereafter, step-down to 2 puffs was performed if either of the following criteria was met at 8-week intervals: fractional exhaled nitric oxide (FeNO)≤28 ppb plus asthma control test (ACT) score≥22, or ACT score≥24 at 3 consecutive visits regardless of FeNO level. Thereafter, changes in ACT score, the number of acute exacerbations and reliever use, and FeNO level were monitored through 48th week. RESULTS: Fifty-one patients, 27 in step3 group and 24 in step4 group, underwent step-down. ACT scores and the number of reliever use remained stable in both groups even after step-down. In contrast, FeNO levels increased gradually in step4 group, whereas in the step3 group they increased immediately after step-down. Step-down was considered to be safely performed because the numbers of reliever use and those of moderate or more severe exacerbations during the 48-week period has not changed significantly compared to before step-down. CONCLUSIONS: If complete control of asthma, not only of clinical symptoms but also airway inflammation, is achieved by 3-6 months of fixed-dose budesonide/formoterol 4 puffs/day, it should be possible to safely perform step-down to 2 puffs/day.

Clinical usefulness of end-tidal CO2 measured using a portable capnometer in patients with respiratory disease.

INTRODUCTION: This study aimed to evaluate the correlation and agreement between end-tidal CO2 (EtCO2 ) measured with the novel portable capnometer (CapnoEye®) and partial pressure of arterial carbon dioxide (PaCO2 ) levels in patients with respiratory diseases and to compare the efficacy of EtCO2 and PvCO2 in predicting PaCO2 levels. METHODS: We analyzed the correlation and the agreement between EtCO2 and PaCO2 and between PvCO2 and PaCO2 using Pearson's moment correlation coefficient in patients with type 1 and type 2 respiratory failure and both groups overall. RESULTS: A total of 100 samples were included that comprised 67 men (67%). The mean age of the subjects was 77 ± 13 years. Chronic obstructive pulmonary disease (COPD) (43%) was the most common disease. There was a high correlation between EtCO2 and PaCO2 (r = 0.88; p < 0.0001). Sixty-six PvCO2 samples were obtained, and there was a high correlation between PvCO2 and PaCO2 (r = 0.81; p < 0.0001). Regarding type 2 respiratory failure, there was a high correlation between EtCO2 and PaCO2 (r = 0.81). The Bland-Altman analysis between PaCO2 and EtCO2 revealed a bias of 5.7 mmHg, with limits of agreement ranging from -5.1 mmHg to 16.5 mmHg. In contrast, the analysis between PaCO2 and PvCO2 revealed a bias of -6.8 mmHg, and the limits of agreement ranged from -22.13 mmHg to 8.53 mmHg. CONCLUSION: EtCO2 measured by CapnoEye® was significantly correlated to PaCO2 levels in patients with respiratory diseases. Moreover, CapnoEye® may be more useful for predicting hypercapnia conditions in which respiratory diseases are compared with measure PvCO2 .

Unexpected Complications 25 Years after Coil Embolization for Pulmonary Arteriovenous Fistula.

An 87-year-old woman who had undergone coil embolization 25 years ago for pulmonary arteriovenous fistula, which was diagnosed following repeated cerebral infarction, presented with massive hemoptysis. The coils migrated and were excreted in stool following hemoptysis during long-term follow-up. Although the technical success rate of coil embolization for pulmonary arteriovenous malformations is extremely high, and coil embolization-related complications are rare, little is known about the long-term complications. We herein report the clinical course of our case, review previous reports related to coil migration as a long-term complication, and discuss the associated mechanism.

A case of idiopathic multicentric Castleman disease with pulmonary hyalinizing granuloma-like multiple pulmonary nodules.

A 41-year-old man presented with chronic cough and chest pain. Laboratory tests revealed anemia, inflammation, hypoalbuminemia, polyclonal hypergammaglobulinemia, and elevated interleukin-6 levels. Computed tomography revealed diffuse bilateral pulmonary nodules and multicentric lymphadenopathy. Histopathology of the pulmonary nodule resembled pulmonary hyalinizing granuloma (PHG), whereas lymph node histopathology was consistent with idiopathic multicentric Castleman disease (iMCD). The patient was diagnosed with iMCD involving PHG-like pulmonary nodules. Little is known about the association between these two diseases, and the present case provides insights regarding the relationship between PHG and iMCD.