The impact of respiratory reactance in oscillometry on survival in patients with idiopathic pulmonary fibrosis.

BACKGROUND: Idiopathic pulmonary fibrosis (IPF) is a progressive disease with a poor prognosis. Pulmonary function tests (PFTs) aid in evaluating the disease status of IPF. The clinical significance of oscillometry measurements in interstitial lung diseases has recently been reported. Our previous study showed that respiratory reactance (Xrs) measured by oscillometry reflected disease severity and predicted subsequent lung capacity decline in patients with IPF. However, the direct impact of Xrs on survival needs to be determined, and there are currently no reference values in oscillometry to predict prognosis. Therefore, this study aimed to investigate the association between oscillometry measurements, particularly Xrs, and survival in patients with IPF and to determine the cutoff values of Xrs that predict 3-year survival. METHODS: We analyzed the relationship between the measured values of PFT and oscillometry derived from 178 patients with IPF. Univariate and multivariate Cox proportional hazards analyses were performed to investigate the relationships between clinical indices at the time of the first oscillometry and survival. We performed the time-dependent receiver operating characteristic (ROC) curve analysis to set the optimized cutoff values of Xrs for 3-year survival prediction. We examined the discriminating power of cutoff values of Xrs on survival using the Kaplan-Meier method and the log-rank test. RESULTS: Xrs components, especially in the inspiratory phase (In), significantly correlated with the PFT values. In the multivariate analyses, Xrs (all of reactance at 5 Hz [X5], resonant frequency [Fres], and low-frequency reactance area [ALX] in the inspiratory phase) had a significant impact on survival (X5, p = 0.003; Fres, p = 0.016; ALX, p = 0.003) independent of age, sex, and other prognostic factors derived from the univariate analysis. The area under the ROC curve was 0.765, 0.759, and 0.766 for X5 In, Fres In, and ALX In, with cutoff values determined at - 0.98, 10.67, and 5.32, respectively. We found significant differences in survival after dividing patients using each of the cutoff values of Xrs. CONCLUSIONS: In patients with IPF, Xrs measured by oscillometry significantly impacted survival. We also determined the cutoff values of Xrs to discriminate patients with poor prognoses.

Deep-learning algorithm to detect fibrosing interstitial lung disease on chest radiographs.

BACKGROUND: Antifibrotic therapies are available to treat chronic fibrosing interstitial lung diseases (CF-ILDs), including idiopathic pulmonary fibrosis. Early use of these treatments is recommended to slow deterioration of respiratory function and to prevent acute exacerbation. However, identifying patients in the early stages of CF-ILD using chest radiographs is challenging. In this study, we developed and tested a deep-learning algorithm to detect CF-ILD using chest radiograph images. METHOD: From the image archive of Sapporo Medical University Hospital, 653 chest radiographs from 263 patients with CF-ILDs and 506 from 506 patients without CF-ILD were identified; 921 were used for deep learning and 238 were used for algorithm testing. The algorithm was designed to output a numerical score ranging from 0 to 1, representing the probability of CF-ILD. Using the testing dataset, the algorithm's capability to identify CF-ILD was compared with that of doctors. A second dataset, in which CF-ILD was confirmed using computed tomography images, was used to further evaluate the algorithm's performance. RESULTS: The area under the receiver operating characteristic curve, which indicates the algorithm's detection capability, was 0.979. Using a score cut-off of 0.267, the sensitivity and specificity of detection were 0.896 and 1.000, respectively. These data showed that the algorithm's performance was noninferior to that of doctors, including pulmonologists and radiologists; performance was verified using the second dataset. CONCLUSIONS: We developed a deep-learning algorithm to detect CF-ILDs using chest radiograph images. The algorithm's detection capability was noninferior to that of doctors.

Programmed Death-Ligand 1-Positive Squamous Cell Carcinoma Spontaneously Regressed after Percutaneous Needle Biopsy.

Spontaneous lung cancer regression is a very rare course of disease. A 60-year-old male patient was admitted to our hospital with pneumonia and a 19 mm-sized nodule shadow in the S4 of the left lung on chest computed tomography (CT). A percutaneous needle biopsy was performed, and a diagnosis of programmed death-ligand 1-positive squamous cell lung carcinoma was made based on pathological findings. The patient was followed up with imaging because the lesion has reduced in size on chest CT. We report the possibility that cellular immune mechanisms triggered by needle biopsy contributed to spontaneous regression.

Pneumocystis jirovecii Pneumonia Associated with COVID-19 in Patients with Interstitial Pneumonia.

Here, we report two cases of patients with interstitial pneumonia (IP) on steroids who developed Pneumocystis jirovecii pneumonia (PJP) following coronavirus disease 2019 (COVID-19) infection. Case 1: A 69-year-old man on 10 mg of prednisolone (PSL) daily for IP developed new pneumonia shortly after his COVID-19 infection improved and was diagnosed with PJP based on chest computed tomography (CT) findings and elevated serum ß-D-glucan levels. Trimethoprim-sulfamethoxazole (TMP-SMZ) was administered, and the pneumonia resolved. Case 2: A 70-year-old woman taking 4 mg/day of PSL for IP and rheumatoid arthritis developed COVID-19 pneumonia, which resolved mildly, but her pneumonia flared up and was diagnosed as PJP based on CT findings, elevated ß-D-glucan levels, and positive polymerase chain reaction for P. jirovecii DNA in the sputum. The autopsy revealed diffuse alveolar damage, increased collagen fiver and fibrotic foci, mucinous component accumulation, and the presence of a P. jirovecii cyst. In conclusion, steroids and immunosuppressive medications are well-known risk factors for PJP. Patients with IP who have been taking these drugs for a long time are frequently treated with additional steroids for COVID-19; thus, PJP complications should be avoided in such cases.

Serum surfactant protein D as a predictive biomarker for the efficacy of pirfenidone in patients with idiopathic pulmonary fibrosis: a post-hoc analysis of the phase 3 trial in Japan.

BACKGROUND: Idiopathic pulmonary fibrosis (IPF) is a progressive, fatal disorder with a variable disease course. The recent advancement of antifibrotic therapy has increased the need for reliable and specific biomarkers. This study aimed to assess alveolar epithelial biomarkers as predictors for the efficacy of the antifibrotic drug pirfenidone. METHODS: We conducted a post-hoc analysis of the prospective, multicenter, randomized, placebo-controlled, phase 3 trial of pirfenidone in Japan (total, n = 267; pirfenidone, n = 163; placebo, n = 104). Logistic regression analysis was performed to extract parameters that predicted disease progression, defined by a ≥ 10% relative decline in vital capacity (VC) from baseline and/or death, at week 52. For assessment of serum surfactant protein (SP)-D, SP-A and Krebs von den Lungen (KL)-6, all patients were dichotomized by the median concentration of each biomarker at baseline to the high and low biomarker subgroups. Associations of these concentrations were examined with changes in VC at each time point from baseline up to week 52, along with progression-free survival (PFS). Additionally, the effect of pirfenidone treatment on serial longitudinal concentrations of these biomarkers were evaluated. RESULTS: In the multivariate logistic regression analysis, body mass index (BMI), %VC and SP-D in the pirfenidone group, and BMI and %VC in the placebo group were indicated as predictors of disease progression. Pirfenidone treatment reduced the decline in VC with statistical significance in the low SP-D and low SP-A subgroups over most of the treatment period, and also prolonged PFS in the low SP-D and low KL-6 subgroups. Furthermore, SP-D levels over time course were reduced in the pirfenidone group from as early as week 8 until the 52-week treatment period compared with the placebo group. CONCLUSIONS: Serum SP-D was the most consistent biomarker for the efficacy of pirfenidone in the cohort trial of IPF. Serial measurements of SP-D might have a potential for application as a pharmacodynamic biomarker. Trial registration The clinical trial was registered with the Japan Pharmaceutical Information Center (JAPIC) on September 13, 2005 (registration No. JapicCTI-050121; http://Clinicaltrials.jp ).

Correction to: Surfactant protein A as a biomarker of outcomes of anti-fibrotic drug therapy in patients with idiopathic pulmonary fibrosis.

Following publication of the original article [1], the authors have flagged that there is an error in Fig. 3.

Surfactant protein A as a biomarker of outcomes of anti-fibrotic drug therapy in patients with idiopathic pulmonary fibrosis.

BACKGROUND: Idiopathic pulmonary fibrosis (IPF) is a progressive and fibrosing lung disease with poor prognosis. Pirfenidone and nintedanib are anti-fibrotic drugs used for patients with IPF. These drugs reduce the rate of decline in forced vital capacity (FVC). Serum surfactant protein (SP)-A, SP-D, and Krebs von den Lungen-6 (KL-6) are monitoring and prognostic biomarkers in patients with IPF; however, their relationship with the therapeutic outcomes of anti-fibrotic drugs has not been investigated. We aim to clarify whether serum SP-A, SP-D, and KL-6 reflect therapeutic outcomes of pirfenidone and nintedanib administration in patients with IPF. METHODS: We retrospectively investigated patients with IPF who were initiated on pirfenidone or nintedanib administration between January 2014 and June 2018 at our hospital. Changes in clinical parameters and serum SP-A, SP-D, and KL-6 levels were evaluated. Patients with ≥10% decline in FVC or ≥ 15% decline in diffusing capacity of the lung for carbon monoxide (DLco) from baseline to 6 months were classified as progression group, while the other patients were classified as stable group. RESULTS: Forty-nine patients were included (pirfenidone, 23; nintedanib, 26). Stable group comprised 32 patients, while progression group comprised 17 patients. In the stable group, changes in SP-A and KL-6 from baseline to 3 and 6 months significantly decreased compared with the progression group (SP-A: 3 months - 6.0% vs 16.7%, 6 months - 10.2% vs 20.2%, KL-6: 3 months - 9.2% vs 6.7%, 6 months - 15.0% vs 12.1%, p < 0.05). Changes in SP-A and SP-D levels showed significant negative correlations with the change in %FVC (r = - 0.46 and r = - 0.39, p < 0.01, respectively) and %DLco (r = - 0.67 and r = - 0.54, p < 0.01, respectively). Similar results were also seen in subgroup analysis for both pirfenidone and nintedanib groups. On logistic regression analysis, decrease in SP-A from baseline to 3 months and 6 months was found to predict the outcomes at 6 months (odds ratios: 0.89 and 0.88, respectively). CONCLUSIONS: Changes in serum SP-A reflected the outcomes of anti-fibrotic drug therapy. Serum SP-A has a potential as a biomarker of therapeutic outcomes of anti-fibrotic drugs.

Activated circulating T follicular helper cells and skewing of T follicular helper 2 cells are down-regulated by treatment including an inhaled corticosteroid in patients with allergic asthma.

BACKGROUND: CXCR5+ T follicular helper (TFH) cells primarily promote B cells to produce an antigen-specific antibody through germinal centers (GCs). TFH cells exist in circulation, and circulating(c) TFH2 cells, a subset of cTFH cells, are able to help naïve B cells produce IgE in healthy individuals. Conversely, IL-10-producing regulatory B (Breg) cells inhibit an accelerated immune response. METHODS: We investigated the roles of cTFH cells and cBreg cells based on a TH2 response in patients with atopic asthma (AA). Thirty-two patients with AA and 35 healthy volunteers (HV) were enrolled. We examined cTFH cells including their subsets, their expression of ICOS and PD-1, and cBreg cells by flow cytometry and their associations with clinical biomarkers. Plasma levels of CXCL13, which is a counterpart of CXCR5, were also measured using ELISA. RESULTS: In patients with AA, cTFH2 cells were increased and cTFH1 cells were decreased compared with those in HV. The expression levels of ICOS on cTFH and their subset cells were elevated and Breg cells were greatly decreased. The plasma levels of CXCL13 in patients with AA were significantly elevated and correlated well with the cTFH2/cBreg ratio. These cells were examined in 10 patients AA before and after inhaled corticosteroid (ICS) treatment. Interestingly, the percentages and numbers of TFH2 and ICOS+ cTFH cells declined after ICS treatment together with improvements in symptoms and clinical biomarkers. CONCLUSIONS: The percentages and numbers of cTFH2 and ICOS+ cTFH cells might be useful as biomarkers of TH2 typed airway inflammation in patients with AA.

Aberrant populations of circulating T follicular helper cells and regulatory B cells underlying idiopathic pulmonary fibrosis.

BACKGROUND: T follicular helper (Tfh) cells have been identified as a new category of helper T cells, which express CXCR5 on their surface and induce the production of antigen-specific antibodies. Many investigations have found morbid proliferation and/or activation of Tfh cells in systemic autoimmune and allergic diseases. It is also known that Tfh cells are regulated by regulatory B (Breg) cells in the deteriorating such diseases. Recently, CXCL13, a ligand of CXCR5, has been reported to increase in the peripheral blood and lungs of patients with idiopathic pulmonary fibrosis (IPF). This study aimed to investigate the involvement of Tfh cells and Breg cells in IPF. METHODS: Peripheral blood samples were obtained from 18 patients with IPF. We isolated heparinized peripheral blood mononuclear cells and investigated the proportions of Breg cells, Tfh cells, PD-1+ICOS+ Tfh cells (activated form of Tfh cells), and the Tfh-cell subsets by flow cytometry. These cell profiles were compared with those of 21 healthy controls. Furthermore, we investigated the correlations between profiles of lymphocytes and lung physiology. RESULTS: The median proportions of Tfh cells per total CD4+ T cells and of PD-1+ICOS+ proportion of Tfh cells per total Tfh cells was significantly more in the IPF patients (20.4 and 5.2%, respectively) compared with healthy controls (15.4 and 2.1%, respectively; p = 0.042 and p = 0.004, respectively). The proportion of Tfh2 cells per total Tfh cells was significantly higher and the proportion of Tfh17 was smaller in the IPF patients than healthy controls. The percentage of Breg cells to total B cells was significantly decreased in the IPF patients (median, 8.5%) compared with that in the controls (median, 19.7%; p < 0.001). The proportion of Breg cells was positively correlated with the annual relative change in diffusing capacity of the lungs for carbon monoxide in the IPF patients (r = 0.583, p = 0.018). CONCLUSION: Proliferation and activation of Tfh cells and a decrease in Breg cells were observed in the peripheral blood of patients with IPF. The profile of the Tfh-cell subset also changed. Specific humoral immunity aberration would likely underlie complicated pathophysiology of IPF.

Feasibility of rapid on-site cytological evaluation of lung cancer by a trained pulmonologist during bronchoscopy examination.

OBJECTIVE: Rapid on-site cytological evaluation (ROSE) in bronchoscopy is a useful ancillary technique. ROSE is usually performed by a cytopathologist or cytotechnologist. However, because of staff shortages and reduced availability, ROSE cannot be performed in every hospital. We aimed to evaluate the accuracy of ROSE when performed by a trained pulmonologist, comparing the diagnosis results with the final diagnosis of cytopathologists. METHODS: We performed a retrospective cohort study on 125 patients who underwent bronchoscopy with endobronchial ultrasound-guided transbronchial needle aspiration (EBUS-TBNA) and endobronchial ultrasonography with a guide sheath (EBUS-GS) for peripheral pulmonary lesions by conventional bronchoscopy at Sapporo Medical University Hospital between March 2012 and September 2018. ROSE was performed by a pulmonologist who was trained by a cytotechnologist for a total of 1 month. DiffQuik® staining for ROSE was used to prepare cytology slides. The results of ROSE were compared with the final diagnosis obtained using Papanicolaou staining by cytopathologists. RESULTS: In all procedures, the sensitivity, specificity and diagnostic accuracy of ROSE were 88.5%, 83.0% and 86.4%, respectively. There was no significant difference in the sensitivity, specificity, positive predictive value, negative predictive value or accuracy between EBUS-TBNA and EBUS-GS. CONCLUSIONS: ROSE of lung cancer by a trained pulmonologist can be highly accurate and deemed as feasible and useful for not only EBUS-TBNA but also EBUS-GS.

Volatile Organic Compounds in Exhaled Breath of Idiopathic Pulmonary Fibrosis for Discrimination from Healthy Subjects.

Purpose Human breath analysis is proposed with increasing frequency as a useful tool in clinical application. We performed this study to find the characteristic volatile organic compounds (VOCs) in the exhaled breath of patients with idiopathic pulmonary fibrosis (IPF) for discrimination from healthy subjects. Methods VOCs in the exhaled breath of 40 IPF patients and 55 healthy controls were measured using a multi-capillary column and ion mobility spectrometer. The patients were examined by pulmonary function tests, blood gas analysis, and serum biomarkers of interstitial pneumonia. Results We detected 85 VOC peaks in the exhaled breath of IPF patients and controls. IPF patients showed 5 significant VOC peaks; p-cymene, acetoin, isoprene, ethylbenzene, and an unknown compound. The VOC peak of p-cymene was significantly lower (p < 0.001), while the VOC peaks of acetoin, isoprene, ethylbenzene, and the unknown compound were significantly higher (p < 0.001 for all) compared with the peaks of controls. Comparing VOC peaks with clinical parameters, negative correlations with VC (r =-0.393, p = 0.013), %VC (r =-0.569, p < 0.001), FVC (r = -0.440, p = 0.004), %FVC (r =-0.539, p < 0.001), DLco (r =-0.394, p = 0.018), and %DLco (r =-0.413, p = 0.008) and a positive correlation with KL-6 (r = 0.432, p = 0.005) were found for p-cymene. Conclusion We found characteristic 5 VOCs in the exhaled breath of IPF patients. Among them, the VOC peaks of p-cymene were related to the clinical parameters of IPF. These VOCs may be useful biomarkers of IPF.

Prolyl isomerase Pin1 promotes survival in EGFR-mutant lung adenocarcinoma cells with an epithelial-mesenchymal transition phenotype.

The secondary epidermal growth factor receptor (EGFR) T790M mutation is the most prominent mechanism that confers resistance to first- or second-generation EGFR tyrosine kinase inhibitors (TKIs) in lung cancer treatment. Although third-generation EGFR TKIs can suppress the kinase activity of T790M-positive EGFR, they still cannot eradicate EGFR-mutated cancer cells. We previously reported that a subpopulation of EGFR-mutant lung adenocarcinomas depends on enhanced autophagy, instead of EGFR, for survival, and in this study we explore another mechanism that contributes to TKI resistance. We demonstrate here that an EGFR-mutant lung adenocarcinoma cell line, H1975 (L858R+T790M), has a subset of cells that exhibits an epithelial-mesenchymal transition (EMT) phenotype and can thrive in the presence of third-generation EGFR TKIs. These cells depend on not only autophagy but also on the isomerase Pin1 for survival in vitro, unlike their parental cells. The Pin1 protein was expressed in an EGFR-mutant lung cancer tissue that has undergone partial EMT and acquired resistance to EGFR TKIs, but not its primary tumor. These findings suggest that inhibition of Pin1 activity can be a novel strategy in lung cancer treatment.

[THE CURRENT SITUATION OF FOREIGN TUBERCULOSIS PATIENTS AND THEIR CONCURRENT HIV INFECTION IN HOKKAIDO].

BACKGROUND AND PURPOSE: According to recent news, patients with concurrent tuberculosis (TB) and human immunodeficiency virus (HIV) infection are increasingly common worldwide. This study aimed to investigate whether TB/HIV co-infected patients are visiting Hokkaido. METHOD: We conducted a questionnaire survey regarding foreign patients infected with TB or TB/HIV who visited Hokkaido between January 2001 and September 2014. We mailed questionnaires to health centers, AIDS treatment care hospitals, and TB hospitals in Hokkaido prefecture. RESULTS: Seventy-one TB patients were of foreign nationality according to the answers obtained from health centers. Most of them were foreign students or occupational trainees between 20-30 years old. Approximately half these patients were from East Asia, and 7 patients were from Africa. As 21 % of the patients with TB who visited medical examination were over 1 month from disease onset, and the delay in visiting was recognized. The TB infection was mostly detected coincidentally during the physician visit. In the hospital survey, four TB patients with HIV were of foreign nationality. They were also of the age group from 20-30 years and hailed from sub-Saharan Africa. DISCUSSION: During immigration, medical examination by performing a chest radiograph is important. If the immigrant hails from an area where TB and HIV co-infection is common, it is necessary to confirm whether HIV infection is present.

Distinct compartmentalization of SP-A and SP-D in the vasculature and lungs of patients with idiopathic pulmonary fibrosis.

BACKGROUND: Surfactant proteins SP-A and SP-D are useful biomarkers in diagnosis, monitoring, and prognosis of idiopathic pulmonary fibrosis (IPF). Despite their high structural homology, their serum concentrations often vary in IPF patients. This retrospective study aimed to investigate distinct compartmentalization of SP-A and SP-D in the vasculature and lungs by bronchoalveolar lavage fluid (BALF)/serum analysis, hydrophilicity and immunohistochemistry. METHODS: We included 36 IPF patients, 18 sarcoidosis (SAR) patients and 20 healthy subjects. Low-speed centrifugal supernatants of BALF (Sup-1) were obtained from each subject. Sera were also collected from each patient. Furthermore, we separated Sup-1 of IPF patients into hydrophilic supernatant (Sup-2) and hydrophobic precipitate (Ppt) by high-speed centrifugation. We measured SP-A and SP-D levels of each sample with the sandwich ELISA technique. We analyzed the change of the BALF/serum level ratios of the two proteins in IPF patients and their hydrophilicity in BALF. The distribution in the IPF lungs was also examined by immunohistochemical staining. RESULTS: In BALF, SP-A levels were comparable between the groups; however, SP-D levels were significantly lower in IPF patients than in others. Although IPF reduced the BALF/serum level ratios of the two proteins, the change in concentration of SP-D was more evident than SP-A. This suggests a higher disease impact for SP-D. Regarding hydrophilicity, although more than half of the SP-D remained in hydrophilic fractions (Sup-2), almost all of the SP-A sedimented in the Ppt with phospholipids. Hydrophilicity suggests that SP-D migrates into the blood more easily than SP-A in IPF lungs. Immunohistochemistry revealed that SP-A was confined to thick mucus-filling alveolar space, whereas SP-D was often intravascular. This data also suggests that SP-D easily leaks into the bloodstream, whereas SP-A remains bound to surfactant lipids in the alveolar space. CONCLUSIONS: The current study investigated distinct compartmentalization of SP-A and SP-D in the vasculature and lungs. Our results suggest that serum levels of SP-D could reflect pathological changes of the IPF lungs more incisively than those of SP-A.

Detection of fibrosing interstitial lung disease-suspected chest radiographs using a deep learning-based computer-aided detection system: a retrospective, observational study.

OBJECTIVES: To investigate the effectiveness of BMAX, a deep learning-based computer-aided detection system for detecting fibrosing interstitial lung disease (ILD) on chest radiographs among non-expert and expert physicians in the real-world clinical setting. DESIGN: Retrospective, observational study. SETTING: This study used chest radiograph images consecutively taken in three medical facilities with various degrees of referral. Three expert ILD physicians interpreted each image and determined whether it was a fibrosing ILD-suspected image (fibrosing ILD positive) or not (fibrosing ILD negative). Interpreters, including non-experts and experts, classified each of 120 images extracted from the pooled data for the reading test into positive or negative for fibrosing ILD without and with the assistance of BMAX. PARTICIPANTS: Chest radiographs of patients aged 20 years or older with two or more visits that were taken during consecutive periods were accumulated. 1251 chest radiograph images were collected, from which 120 images (24 positive and 96 negative images) were randomly extracted for the reading test. The interpreters for the reading test were 20 non-expert physicians and 5 expert physicians (3 pulmonologists and 2 radiologists). PRIMARY AND SECONDARY OUTCOME MEASURES: The primary outcome was the comparison of area under the receiver-operating characteristic curve (ROC-AUC) for identifying fibrosing ILD-positive images by non-experts without versus with BMAX. The secondary outcome was the comparison of sensitivity, specificity and accuracy by non-experts and experts without versus with BMAX. RESULTS: The mean ROC-AUC of non-expert interpreters was 0.795 (95% CI; 0.765 to 0.825) without BMAX and 0.825 (95% CI; 0.799 to 0.850) with BMAX (p=0.005). After using BMAX, sensitivity was improved from 0.744 (95% CI; 0.697 to 0.791) to 0.802 (95% CI; 0.754 to 0.850) among non-experts (p=0.003), but not among experts (p=0.285). Specificity and accuracy were not changed after using BMAX among either non-expert or expert interpreters. CONCLUSION: BMAX was useful for detecting fibrosing ILD-suspected chest radiographs for non-expert physicians. TRIAL REGISTRATION NUMBER: jRCT1032220090.

Bob1 maintains T follicular helper cells for long-term humoral immunity.

Humoral immunity is vital for host protection, yet aberrant antibody responses can trigger harmful inflammation and immune-related disorders. T follicular helper (Tfh) cells, central to humoral immunity, have garnered significant attention for unraveling immune mechanisms. This study shows the role of B-cell Oct-binding protein 1 (Bob1), a transcriptional coactivator, in Tfh cell regulation. Our investigation, utilizing conditional Bob1-deficient mice, suggests that Bob1 plays a critical role in modulating inducible T-cell costimulator expression and cellular respiration in Tfh cells. This regulation maintains the long-term functionality of Tfh cells, enabling their reactivation from central memory T cells to produce antibodies during recall responses. In a bronchial asthma model induced by house dust mite (HDM) inhalation, Bob1 is observed to enhance HDM-specific antibodies, including IgE, highlighting its pivotal function in Tfh cell regulation. Further exploration of Bob1-dependent mechanisms in Tfh cells holds promise for governing protective immunity and addressing immune-related disorders.

Coronavirus Disease 2019 Vaccine-Induced Flare-Up of Severe Bronchial Asthma Previously Controlled With Dupilumab: A Case Report.

The widespread after-effects of the coronavirus disease 2019 (COVID-19) are still a grave threat worldwide. Among them are adverse reactions to vaccines, including those most observed following Pfizer-BioNTech (BNT162b2) vaccine administration, namely, local reactions at the injection site, fatigue, headache, myalgia, chills, arthralgia, and fever. Patients with asthma particularly present with unique adverse reactions to the BNT162b2 vaccine, notably, an exacerbation in their asthma symptoms as highlighted through the current case report. In this case, a 50-year-old woman had been undergoing treatment for bronchial asthma in the form of inhalation steroids and dupilumab, as well as systemic steroid prednisolone as maintenance therapy. She had mild injection site reactions after her first three COVID-19 vaccinations. She also experienced acute exacerbation requiring hospitalization after the fourth and fifth doses. Her symptoms resolved following steroid therapy. The close association between the timing of vaccinations and the onset of clinical symptoms suggests that the exacerbation episodes were triggered by the vaccine. Therefore, although the BNT162b2 vaccine is safe to administer in patients with bronchial asthma, cases reporting patients sensitized to the BNT162b2 vaccine developing bronchial asthma or experiencing asthma exacerbations should not be neglected. Clinicians should be aware of the possibility of flare-ups induced by repeated COVID-19 vaccinations in such patients.

The Soluble Lectin Families as Novel Biomarkers for COVID-19 Pneumonia.

BACKGROUND/AIM: The lung-specific soluble lectins, SP-A and SP-D have been clinically used to diagnose interstitial lung disease, but their clinical significance in COVID-19 remains controversial. This study was undertaken to determine their association with other lectins (MBL and FCN1), disease severity, and radiographs in COVID-19 patients. PATIENTS AND METHODS: A total of 131 patients with COVID-19 admitted in the Sapporo Medical University Hospital between May 22 and September 19, 2021, were enrolled in the study. Data including demographics, medical history, symptoms, signs, laboratory findings, and radiological images were collected from the patients' medical records. Chest computed tomography (CT) scanning was performed at admission. Serum levels of surfactant protein A and D (SP-A and SP-D), mannose-binding lectin (MBL) and ficolin1 (FCN1) were measured using enzyme-linked immunosorbent assay (ELISA) kits. RESULTS: Compared to the control group, the COVID-19 group had significantly higher serum SP-A and FCN1 levels on admission (SP-A: 59.60±38.89 vs. 35.61±11.22 ng/ml; p<0.01, FCN1: 542.45±506.04 vs. 250.6±161.1 ng/ml; p<0.01). The severe group in COVID-19 had significantly higher serum SP-D and lower MBL levels than the non-severe group (SP-D: 141.7±155.7 vs. 61.41±54.54 ng/ml; p<0.01, MBL: 1,670±1,240 vs. 2,170±1,140 ng/ml; p<0.05). SP-D strongly reflected the degree of imaging findings, whereas SP-A showed a significant correlation, albeit slightly weaker than SP-D. Conversely, MBL and FNC1 were not significantly correlated with imaging findings. CONCLUSION: Among soluble serum lectins, SP-A and SP-D may be more sensitive to CT findings than reported disease biomarkers such as IL-6, LDH, and CRP due to their lung-specific characteristics.

Pneumocystis Pneumonia Infection Following the Initiation of Pembrolizumab Therapy for Lung Adenocarcinoma.

Pneumocystis pneumonia (PCP) is an opportunistic infection that presents a ground-glass appearance in the lungs on chest radiography. Interstitial lung disease is a commonly reported adverse effect of immune checkpoint inhibitor (ICI) treatment; however, there are few reports of ICI treatment-associated PCP infection. A 77-year-old man with lung adenocarcinoma was administered pembrolizumab and hospitalized for dyspnea 2 weeks after treatment. Chest computed tomography showed bilateral ground-glass opacities in all lung lobes. PCP was therefore diagnosed, and steroids and sulfamethoxazole-trimethoprim were initiated. Following treatment, the patient's condition improved promptly. This report suggests that ICI treatment can cause PCP infection.

Usefulness of cell block examination for the cytological diagnosis of thoracic SMARCA4-deficient undifferentiated tumor: A case report.

SMARCA4-deficient undifferentiated tumor (SMARCA4-UT) is a high-grade malignant neoplasm showing undifferentiated or rhabdoid morphology that significantly involves the thorax of adults. It has been reported as SMARCA4-deficient thoracic sarcoma or SMARCA4-deficient non-small cell lung carcinoma according to the findings of immunohistochemical and genetic studies. We report a case of thoracic SMARCA4-UT for which cell block analysis and immunohistochemical staining were useful for the final diagnosis. A 51-year-old man had a chief complaint of left back pain and visited our hospital for further examination. Cytological examination of a left pleural effusion was performed and we also made a cell block of the pleural effusion. Cytological examination revealed polyhedral to round tumor cells. The tumor cells appeared singly or formed loosely cohesive clusters. The nuclei were round to oval, enlarged, and sometimes eccentric with prominent nucleoli with irregular borders. The nuclear chromatin was unevenly distributed. The cytoplasm was vacuolar to eosinophilic. There were no characteristic structures of tumor cells. The cell block revealed many single or loosely cohesive round to epithelioid cells. Some tumor cells often exhibited eccentrically located nuclei and lightly eosinophilic cytoplasm, showing a rhabdoid morphology. On immunohistochemistry, the tumor cells were positive for SOX-2 and they demonstrated significantly reduced SMARCA4 (BRG1) expression; SMARCA2 (BRM) and SMARCB1 (INI1) expression were retained. Accordingly, we made a diagnosis of SMARCA4-UT. This case demonstrates the importance of performing histological and immunohistochemical analysis using cell blocks for immediate diagnosis.