Benralizumab treatment reduces exacerbations and improves symptom control and quality of life in patients with severe eosinophilic asthma. However, the determination of biomarkers that predict therapeutic effectiveness is required for precision medicine. Herein, we elucidated the dynamics of various parameters before and after treatment as well as patient characteristics predictive of clinical effectiveness after 1 year of benralizumab treatment in severe asthma in a real-world setting. Thirty-six patients with severe asthma were treated with benralizumab for 1 year. Lymphocyte subsets in peripheral blood samples were analyzed using flow cytometry. Treatment effectiveness was determined based on the ACT score, forced expiratory volume in 1 s (FEV1), and the number of exacerbations. Benralizumab provided symptomatic improvement in severe asthma. Benralizumab significantly decreased peripheral blood eosinophil and basophil counts and the frequencies of regulatory T cells (Tregs), and increased the frequencies of Th2 cells. To our knowledge, this is the first study to show benralizumab treatment increasing circulating Th2 cells and decreasing circulating Tregs. Finally, the ROC curve to discriminate patients who achieved clinical effectiveness of benralizumab treatment revealed that the frequency of circulating Th17 cells and FeNO levels might be used as parameters for predicting the real-world response of benralizumab treatment in patients with severe asthma.

The mitogen-activated protein kinase (MAPK) signaling pathway is involved in the epithelial–mesenchymal transition (EMT) and asthma; however, the role of mitogen-activated protein kinase kinase kinase 19 (MAP3K19) remains uncertain. Therefore, we investigated the involvement of MAP3K19 in in vitro EMT and ovalbumin (OVA)-induced asthma murine models. The involvement of MAP3K19 in the EMT and the production of cytokines and chemokines were analyzed using a cultured bronchial epithelial cell line, BEAS-2B, in which MAP3K19 was knocked down using small interfering RNA. We also evaluated the involvement of MAP3K19 in the OVA-induced asthma murine model using Map3k19-deficient (MAP3K19^−/−) mice. Transforming growth factor beta 1 (TGF-β1) and tumor necrosis factor-like weak inducer of apoptosis (TWEAK) induced the MAP3K19 messenger RNA (mRNA) expression in the BEAS-2B cells. The knockdown of MAP3K19 enhanced the reduction in E-cadherin mRNA and the production of regulated upon activation normal T cell express sequence (RANTES) via stimulation with TWEAK alone or with the combination of TGF-β1 and TWEAK. Furthermore, the expression of MAP3K19 mRNA was upregulated in both the lungs and tracheas of the mice in the OVA-induced asthma murine model. The MAP3K19^−/− mice exhibited worsened eosinophilic inflammation and an increased production of RANTES in the airway epithelium compared with the wild-type mice. These findings indicate that MAP3K19 suppressed the TWEAK-stimulated airway epithelial response, including adhesion factor attenuation and RANTES production, and suppressed allergic airway inflammation in an asthma mouse model, suggesting that MAP3K19 regulates allergic airway inflammation in patients with asthma.

Diffuse interstitial lung diseases (ILD) include conditions with identifiable causes such as chronic eosinophilic pneumonia (CEP), sarcoidosis (SAR), chronic hypersensitivity pneumonitis (CHP), and connective tissue disease-associated interstitial pneumonia (CTD), as well as idiopathic interstitial pneumonia (IIP) of unknown origin. In non-IIP diffuse lung diseases, bronchoalveolar lavage (BAL) fluid appearance is diagnostic. This study examines lymphocyte subsets in BAL fluid and peripheral blood of 56 patients with diffuse ILD, excluding idiopathic pulmonary fibrosis (IPF), who underwent BAL for diagnostic purposes. Patients were classified into CEP, SAR, CHP, CTD, and IIP groups, and clinical data, BAL cell analysis, and peripheral blood mononuclear cell analysis were compared. Eosinophils and type 3 innate lymphocytes (ILC3s) were significantly increased in the BAL fluid of the CEP group. Receiver operating characteristic curve analysis identified eosinophils ≥ 8% in BAL cells and ILC3s ≥ 0.0176% in the BAL lymphocyte fraction as thresholds distinguishing CEP. SAR patients exhibited significantly elevated CD4/CD8 ratios in the BAL fluid, with a ratio of 3.95 or higher and type 1 innate lymphoid cell frequency ≥ 0.254% as differentiation markers. High Th1 cell frequency (≥17.4%) in BAL lymphocytes in IIP, elevated serum KL-6 (≥2081 U/mL) and SP-D (≥261 ng/mL) in CHP, and increased BAL neutrophils (≥2.0%) or a low CD4/CD8 ratio (≤1.2) in CTD serve as distinguishing markers for each ILD. Excluding CEP and SAR, CD4⁺ T cell frequencies, including Th1, Th17, and Treg cells in peripheral blood, may differentiate IIP, CHP, and CTD.

Allergen immunotherapy is a promising treatment for allergic diseases that induce immune tolerance through the administration of specific allergens. In this study, we investigate the efficacy of sublingual immunotherapy (SLIT) in asthmatic patients with SAR-JCP and the dynamics of the parameters before and after treatment in a real-world setting. This was a prospective single-center observational study. Patients with asthma and SAR-JCP (n = 24) were recruited for this study and assessed using symptom questionnaires before SLIT and a year after the SLIT. In addition, a respiratory function test, forced oscillation technique, and blood sampling test were performed during the off-season before and after SLIT. The one-year SLIT for asthma patients with SAR-JCP significantly improved not only allergic rhinitis symptoms, but also asthma symptoms during the JCP dispersal season, and significantly improved airway resistance during the off-season. The change in the asthma control test and the visual analog scale score during the season before and after SLIT was negatively and positively correlated with the change in peripheral blood γδ T cells off-season before and after SLIT, respectively. It was suggested that improvement in asthma symptoms during the JCP dispersal season after SLIT was associated with reduced peripheral blood γδ T cells.

Background: Eosinophilic granulomatosis with polyangiitis (EGPA) is a rare systemic vasculitis characterized by eosinophilic inflammation and involvement of small- to medium-sized vessels. Given its heterogeneous clinical presentation, early diagnosis and appropriate management are critical. Although systemic corticosteroids remain the mainstay of therapy, concerns regarding their long-term adverse effects underscore the growing need for alternative treatment strategies. Case Presentation: A 70-year-old man with a medical history of sinusitis, eosinophilic pneumonia, and bronchial asthma was referred for assessment of pleural effusion, which resolved spontaneously at the time of presentation. The patient was observed without intervention, while continuing asthma management. Approximately 6 months later, the patient experienced exacerbation of asthma and recurrence of pleural effusion. Thoracentesis was performed for symptom relief and benralizumab (30 mg) was initiated, resulting in temporary clinical improvement. However, after the third dose, the patient developed abdominal pain, peripheral neuropathy, and a skin rash. Laboratory studies revealed peripheral eosinophilia and elevated levels of rheumatoid factor (RF), myeloperoxidase–anti-neutrophil cytoplasmic antibody (MPO–ANCA), and total immunoglobulin E (IgE). A second skin biopsy revealed granulomatous inflammation, confirming the diagnosis of EGPA. Mepolizumab treatment (300 mg) was initiated, resulting in clinical resolution. Conclusion: This case highlights that EGPA may develop during anti-IL-5 therapy. Close monitoring of clinical signs, along with biomarkers such as eosinophil count, RF, MPO–ANCA, and IgE, is essential for timely diagnosis. Furthermore, successful disease control by switching to mepolizumab monotherapy suggests the potential for managing EGPA using appropriate biologic regimens to minimize corticosteroid-related adverse effects. Further accumulation of similar cases and larger studies is warranted to inform future clinical practice.

Cancer patients are considered highly susceptible to severe acute respiratory syndrome coronavirus 2 (SARS‐CoV‐2) infection. However, it is not well known when chemotherapy can be safely restarted in cancer patients after coronavirus disease 2019 (COVID‐19). Here, we describe the case of an 18‐year‐old man diagnosed with primary mediastinal nonseminomatous germ cell tumor (PMNSGCT) in which chemotherapy could be safely restarted after COVID‐19. On day 11 of the third cycle of bleomycin, etoposide, plus cisplatin (BEP), he was diagnosed with mild COVID‐19. On day 16 after the onset of COVID‐19 (day 26 of third cycle of BEP), chemotherapy for his PMNSGCT was restarted. He received surgery after the fourth cycle of BEP without recurrence of COVID‐19. Chemotherapy could be restarted and followed by surgery in this post‐COVID‐19 patient who had experienced mild illness after the discharge criteria were met and all symptoms had disappeared. We report this case with a review of the literature on restarting chemotherapy after SARS‐CoV2 infection.