Gargle sample is an effective option in a novel fully automated molecular point-of-care test for influenza: a multicenter study

BACKGROUND

We conducted a multicenter study to evaluate the performance of a novel fully automated molecular point-of-care test using transcription-reverse transcription concerted reaction that can detect influenza A and B within 15 min in nasopharyngeal swabs and gargle samples (TRCsatFLU).

METHODS

Patients who visited or were hospitalized at eight clinics and hospitals with influenza-like illnesses between December 2019 and March 2020 participated in this study. We collected nasopharyngeal swabs from all patients and gargle samples from patients whom the physician judged fit to perform gargling. The result of TRCsatFLU was compared to a conventional reverse transcription-polymerase chain reaction (RT-PCR). If the results of TRCsatFLU and conventional RT-PCR were different, the samples were analyzed by sequencing.

RESULTS

We evaluated 233 nasopharyngeal swabs and 213 gargle samples from 244 patients. The average age of the patients was 39.3 ± 21.2. Of the patients, 68.9% visited a hospital within 24 h of symptom onset. The most common symptoms were fever (93.0%), fatigue (79.5%), and nasal discharge (64.8%). All patients in whom the gargle sample was not collected were children. Influenza A or B was detected in 98 and 99 patients in nasopharyngeal swabs and gargle samples using TRCsatFLU, respectively. Four and five patients in nasopharyngeal swabs and gargle samples, respectively, with different TRCsatFLU and conventional RT-PCR results. Influenza A or B was detected using sequencing in all samples with different results. Based on the combined conventional RT-PCR and sequencing results, the sensitivity, specificity, positive predictive value (PPV), and negative predictive value (NPV) of TRCsatFLU for influenza detection in nasopharyngeal swabs were 0.990, 1.000, 1.000, and 0.993, respectively. In the gargle samples, the sensitivity, specificity, PPV, and NPV of the TRCsatFLU for detecting influenza were 0.971, 1.000, 1.000, and 0.974, respectively.

CONCLUSIONS

The TRCsatFLU showed great sensitivity and specificity for the detection of influenza in nasopharyngeal swabs and gargle samples.

TRIAL REGISTRATION

This study was registered in the UMIN Clinical Trials Registry (reference number: UMIN000038276) on October 11, 2019. Before sample collection, written informed consent for the participation and publication of this study was obtained from all participants.

A phase 2/3 study of S-217622 in participants with SARS-CoV-2 infection (Phase 3 part)

BACKGROUND

Limited treatment options exist for patients with mild-to-moderate coronavirus disease 2019 (COVID-19), irrespective of vaccination history or risk status. Ensitrelvir is a novel oral severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) 3C-like (3CL) protease inhibitor. While phase 2 studies of ensitrelvir have demonstrated promising results in treating mild-to-moderate COVID-19, evaluation of its clinical efficacy due to shifting vaccination status and emergence of the Omicron variant represents significant challenges. Here, we describe the protocol for a phase 3 study designed to evaluate the efficacy and safety of ensitrelvir in patients with mild-to-moderate COVID-19, regardless of risk status or vaccination history.

METHODS

This is a multicenter, randomized, double-blind, placebo-controlled, phase 3 study. Patients with mild-to-moderate COVID-19 within 120 hours from onset will be randomized in a 1:1:1 ratio into 3 treatment arms-ensitrelvir 125 mg (375 mg loading dose on Day 1), ensitrelvir 250 mg (750 mg loading dose on Day 1), and placebo. The study interventions will be administered orally, once-daily, for 5 days. The primary endpoint will be the time to resolution of 5 symptoms of COVID-19 (stuffy or runny nose, sore throat, cough, feeling hot or feverish, and low energy or tiredness), and the key secondary endpoints will include the change from baseline on Day 4 in the amount of SARS-CoV-2 viral ribonucleic acid (RNA) and the time to first negative SARS-CoV-2 viral titer. The primary population for the primary and key secondary endpoints will be patients with <72 hours from COVID-19 onset to randomization and, subsequently, patients in entire patient population (<120 hours) in the ensitrelvir 125 mg group. Closed testing procedure will be used for the primary and key secondary endpoints in both the primary and entire patient populations. All safety assessments and adverse events (AE) will be reported.

DISCUSSION

In a post hoc analysis of the phase 2b study, compared with placebo, ensitrelvir demonstrated a reduced time to resolution of 5 symptoms in patients with mild-to-moderate COVID-19. Through this study, we intend to validate and establish the efficacy and safety of ensitrelvir in patients with mild-to-moderate COVID-19.

Evaluation of efficacy and safety of lascufloxacin for nursing and healthcare associated pneumonia: single-arm, open-label clinical trial: A study protocol

BACKGROUND

Lascufloxacin hydrochloride (LSFX) is a quinolone antibiotic that inhibits DNA gyrase and topoisomerase IV of bacteria, it is anticipated to minimize antibiotic resistance in bacteria. It exhibits antibacterial activity against a relatively wide range of bacterial species, including anaerobic bacteria, and its efficacy and safety against community-acquired pneumonia have been shown; however, its efficacy and safety against nursing and healthcare associated pneumonia (NHCAP) have not been verified.

METHODS/DESIGN

Here, a single-arm, open-label, uncontrolled study was conducted in which LSFX was administered to patients with NHCAP at 24 facilities. The research subjects (77 cases) were orally administered 75 mg of LSFX once a day for 7 days. The primary endpoint was the clinical efficacy at the time of test of cure (TOC) (TOC; 5-10 days after the end of LSFX administration), while the secondary endpoints were the efficacy at the time of end of treatment, early clinical efficacy, microbiological efficacy at the time of TOC and end of treatment, and safety evaluation of LSFX.

DISCUSSION

NHCAP is a common pneumonia in clinical settings and a notable pneumonia whose mortality is high compared to community-acquired pneumonia. The present study showed the efficacy and safety of LSFX against NHCAP, which could lead to a larger number of therapeutic options for NHCAP.

Efficacy and safety of isavuconazole against deep-seated mycoses: A phase 3, randomized, open-label study in Japan

OBJECTIVES

Isavuconazole is a convenient triazole antifungal agent with a broad antifungal spectrum. A randomized, open-label study (ClinicalTrials.gov, NCT03471988) was conducted to evaluate the efficacy and safety of isavuconazole in Japanese patients with deep-seated mycoses.

PATIENTS AND METHODS

In Cohort A, patients with aspergillosis (chronic pulmonary aspergillosis and invasive aspergillosis) were randomized in a 2:1 ratio to isavuconazole or voriconazole, and in Cohort B, patients with cryptococcosis and mucormycosis were assigned to isavuconazole for up to 84 days of treatment. The overall outcome was evaluated according to the clinical, radiological, and mycological responses at Days 42 and 84 and at the end of treatment (EOT).

RESULTS

A total of 103 participants were enrolled and received the study drug. The overall response rate of patients with chronic pulmonary aspergillosis in the isavuconazole (52 patients) and voriconazole (27 patients) groups was 82.7% and 77.8% at EOT, respectively. The response rate in patients with cryptococcosis (10 patients, isavuconazole group only) was 90.0%. One of three participants with invasive aspergillosis and one of three participants with mucormycosis responded in the isavuconazole group. In the safety evaluation, the incidence of adverse events in participants with chronic pulmonary aspergillosis was similar in both groups. Adverse drug reactions were reported in 32 (61.5%) patients receiving isavuconazole and 23 (85.2%) patients receiving voriconazole.

CONCLUSIONS

Isavuconazole showed efficacy and safety in Japanese patients with chronic pulmonary aspergillosis and cryptococcosis, for which the drug is not currently indicated.

Pulmonary and Intestinal Involvement in a Patient with Myeloperoxidase-specific Antineutrophil Cytoplasmic Antibody-positive Hermansky-Pudlak Syndrome

A 26-year-old Japanese woman was admitted with a 1-month history of diarrhea, a high fever for a few days, and exacerbation of dyspnea. She was treated with an antifibrotic drug and long-term oxygen therapy for Hermansky-Pudlak syndrome-related pulmonary fibrosis. New ground-glass attenuation appeared on chest computed tomography (CT), and a colon biopsy showed an inflammatory cell accumulation with a high titer of myeloperoxidase (MPO)-specific anti-neutrophil cytoplasmic antibodies (ANCA). Systemic inflammation related to MPO-ANCA titer elevation was suspected. Steroid pulse therapy and intravenous cyclophosphamide improved chest CT findings and diarrhea. Therefore, immunosuppressant treatment should be considered for systemic inflammation related to MPO-ANCA.

Pulmonary Nodular Lymphoid Hyperplasia Evaluated with Bronchoalveolar Lavage Fluid Findings: A Case Report and Review of the Literature on Japanese Patients

Pulmonary nodular lymphoid hyperplasia (PNLH) is a very rare disease, and it is difficult to diagnose PNLH and distinguish it from mucosa-associated lymphoid tissue (MALT) lymphoma. In addition, information on bronchoalveolar lavage fluid (BALF) analyses is lacking. We herein report a 36-year-old Japanese woman diagnosed with PLNH by a surgical biopsy and analysis of BALF. The BALF showed an increase in B-cell marker-positive lymphocytes, normal patterns of B-cell clonality, mucosa-associated lymphoid tissue 1 gene, and immunoglobulin heavy chain at 14q32 translocations. We also reviewed Japanese cases of PNLH described in Japanese or English to explore the characteristics of such cases.

Novel SPEF2 Variant in a Japanese Patient with Primary Ciliary Dyskinesia: A Case Report and Literature Review

Primary ciliary dyskinesia (PCD) is a genetic and congenital disease associated with an abnormal ciliary ultrastructure and function and is estimated to affect 1 in 15,000-20,000 individuals. A PCD diagnosis can be achieved by genotyping. Here, we performed whole-exome analysis for the diagnosis of PCD and described the detailed clinical characteristics of the case. A 39-year-old Japanese woman with sinusitis and bronchiectasis without situs inversus had had upper and lower respiratory symptoms since childhood and had received long-term macrolide therapy without an accurate diagnosis. A moderate deterioration of cilia function was observed by high-speed video microscopy analysis; additionally, the number of cells with moving cilia was fewer than that in patients without PCD. Electron microscopy revealed no apparent structural abnormalities. We performed whole-exome analysis and identified novel biallelic variants of SPEF2 in the homozygous state (c.1860_1861insCT). We confirmed the absence of SPEF2 protein expression in the cilia of the nasal mucosa using fluorescent immunostaining. Accordingly, she was diagnosed as having PCD with the SPEF2 variant. The present case suggests that the deterioration of cilia function is moderate, the number of respiratory cells with moving cilia might be reduced, and the respiratory condition could be severe in patients with PCD with the SPEF2 variant.

Efficacy and safety of ensitrelvir in patients with mild-to-moderate COVID-19: the phase 2b part of a randomized, placebo-controlled, phase 2/3 study

Background

This phase 2b part of a randomized phase 2/3 study assessed the efficacy and safety of ensitrelvir for mild-to-moderate coronavirus disease 2019 (COVID-19) during the Omicron epidemic.

Methods

Patients were randomized (1:1:1) to orally receive ensitrelvir fumaric acid 125 mg (375 mg on day 1) or 250 mg (750 mg on day 1) or placebo once daily for 5 days. The co-primary endpoints were the change from baseline in the severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) titer on day 4 and time-weighted average change from baseline up to 120 hours in the total score of predefined 12 COVID-19 symptoms. Safety was assessed through adverse events.

Results

A total of 341 patients (ensitrelvir 125 mg group, 114; ensitrelvir 250 mg group, 116; and placebo group, 111; male, 53.5%–64.9%; mean age, 35.3–37.3 years) were included in the efficacy analyses. The change from baseline in the SARS-CoV-2 titer on day 4 was significantly greater with both ensitrelvir doses than with placebo (differences from placebo: -0.41 log10 50% tissue-culture infectious dose/mL, P &lt; 0.0001 for both). The total score of the 12 COVID-19 symptoms did not show a significant difference between the ensitrelvir groups and placebo group. The time-weighted average change from baseline up to 120 hours was significantly greater with ensitrelvir versus placebo in several subtotal scores, including acute symptoms and respiratory symptoms. Most adverse events were mild in severity.

Conclusions

Ensitrelvir treatment demonstrated a favorable antiviral efficacy and potential clinical benefit with an acceptable safety profile.

Abstract A61: Development of automated immunoassay to detect serum biomarkers predicting response to immune checkpoint inhibitors in NSCLC

Introduction: Immunotherapy with immune checkpoint inhibitors (ICI) is the standard of care for advanced non-small-cell lung cancer (NSCLC) without driver gene alterations. However, survival benefits with ICI are limited to a small subset of NSCLC patients, and particularly ICI combinations with cytotoxic agents produce serious physical and large financial toxicities. Tumor PD-L1 expression levels/proportion score (TPS) are universally used as predictive biomarkers in ICI monotherapy response and outcomes. However, PD-L1/TPS assays are imperfect because of low analytical validity and reproducibility due to the visual-scoring system by pathologists. Therefore, additional biomarkers are urgently needed to predict ICI therapy response and outcomes. Recently, we reported that serum antibodies (Abs) against NY-ESO-1 and XAGE1 cancer-testis antigens were probably useful biomarkers in the prediction of clinical benefits with anti-PD-1 monotherapy for NSCLC (J Thorac Oncol, 2019). Additionally, we developed a fully automated immunoassay system (HISCLTM) to measure the Abs easily and rapidly (Sakai Y, et al. Clin Chim Acta 2021). In this study, we retrospectively examined whether the Abs measured by HISCLTM predict the clinical benefits with ICI monotherapy for NSCLC.Patients and Methods: Sera were obtained from controls of non-malignant lung diseases (n=75) and healthy subjects (n=100), and advanced NSCLC patients (n=263) to to determine a cutoff value in HISCLTM. In NSCLC patients analyzed here (n=78), sera were obtained before anti-PD-1 monotherapy with nivolumab in second-line or later settings. The serum NY-ESO-1/XAGE1 Abs were measured by HISCLTM, and we examined the relationships between the Abs levels, objective response rate (ORR), progression free survival (PFS), and overall survival (OS) after nivolumab monotherapy.Results: NY-ESO-1/XAGE1 Abs levels in NSCLC patients (n=263) were significantly higher than those in the controls (n=175). A cutoff value was determined as the Abs level of 10 SU/mL, calculated from the Abs values in the controls. The Abs (≥ 10 SU/mL) were detected in 21/78 (27%) of the NSCLC patients treated with nivolumab, and one patient had both NY-ESO-1 and XAGE1 Ab. An ORR was 62%, 16%, and 29% in the Abs-positives, the Abs-negatives, and overall, respectively. The Abs levels in responders were significantly higher than those in non-responders. The NSCLC patients with high-Abs values (≥ 10 SU/mL) had significantly better survivals with nivolumab monotherapy than those with low-Abs (PFS, HR 0.51, 95%CI 0.31-0.83, p &lt; 0.01; OS, HR 0.51, 95%CI 0.31-0.84, p &lt; 0.01). Interestingly, a few NSCLC patients with both high-Abs and driver genes responded well to nivolumab.Conclusions: Serum NY-ESO-1/XAGE1 Abs measured by HISCLTM are potential biomarkers that predict clinical benefits with anti-PD-1 monotherapy for NSCLC, even including driver genes. These findings warrant further biomarker studies using NY-ESO-1/XAGE1 Abs in clinical trial and practice of NSCLC immunotherapy.

Citation Format: Kanako Sakaeda, Koji Kurose, Minoru Fukuda, Nanae Sugasaki, Akitoshi Kinoshita, Takashi Kitazaki, Masaaki Fukuda, Takeshi Masuda, Noboru Hattori, Yusuke Atarashi, Yumiko Sakai, Yasuhiro Irino, Mami Yamaki, Toshiyuki Sato, Hiroshi Mukae, Toru Oga, Mikio Oka. Development of automated immunoassay to detect serum biomarkers predicting response to immune checkpoint inhibitors in NSCLC [abstract]. In: Proceedings of the AACR Special Conference: Tumor Immunology and Immunotherapy; 2022 Oct 21-24; Boston, MA. Philadelphia (PA): AACR; Cancer Immunol Res 2022;10(12 Suppl):Abstract nr A61.

Interstitial Pneumonia with HLA-B54 Antigen that Responded Well to Erythromycin

A 65-year-old Japanese man with interstitial pneumonia demonstrated honeycomb lung with thickened walls on chest high-resolution computed tomography (HRCT) and predominance of neutrophils in the cell fraction of the bronchoalveolar lavage fluid. Although there were no centrilobular nodular or branching shadows on chest HRCT suggestive of diffuse panbronchiolitis, he exhibited sinusitis and had the human leukocyte antigen (HLA)-B54 antigen. With long-term macrolide therapy, the cough and sputum production markedly improved, wall thickening of the honeycomb lung on chest HRCT decreased, and the forced vital capacity increased. Confirming the presence of HLA-B54 antigen may help determine the indication for long-term macrolide therapy in interstitial pneumonia patients.

Immune checkpoint therapy and response biomarkers in non-small-cell lung cancer: Serum NY-ESO-1 and XAGE1 antibody as predictive and monitoring markers

Immune checkpoint inhibitors (ICI) are key drugs in systemic therapy for advanced non-small-cell lung cancer (NSCLC) and have recently been incorporated into neoadjuvant and adjuvant settings for surgical resection. Currently, ICI combinations with cytotoxic agents are frequently used in clinical practice, although several ICI clinical trials have failed to produce long-term clinical benefits. Unfortunately, clinical benefit is moderate and limited considering physical and financial burden. Therefore, selecting appropriate patients and regimens for ICI therapy is important, and biomarkers are necessary for their selection. Tumor PD-L1 expression is universally used as a biomarker; however, PD-L1 assays show low analytical validity and reproducibility due to the visual-scoring system by pathologists. Recent tumor immunology studies explore that neoantigens derived from somatic mutations and the collaboration between T and B cells efficiently elicit antitumor responses. This suggests that high tumor mutational burden and T-cell infiltration are predictive biomarkers. However, B cells producing antibody (Ab) remain poorly understood and analyzed as biomarkers. We found that NY-ESO-1 and XAGE1 of cancer-testis antigen frequently elicit spontaneous humoral and cellular immune responses in NSCLC. Serum Ab against these antigens were detected in approximately 25% of NSCLC patients and predicted ICI monotherapy responses. In addition, the Ab levels were decreased with tumor shrinkage after ICI therapy. Thus, NY-ESO-1 and XAGE1 Ab are potentially biomarkers predicting and monitoring response to ICI therapy. For clinical applications, a fully-automated assay system measuring the Ab was developed. Here, we review current ICI therapy, tumor immunology, and biomarkers in NSCLC, and discuss the applicability of the serum biomarkers NY-ESO-1 and XAGE1 Ab.

Clinical evaluation of a fully automated and high-throughput molecular testing system for detection of influenza virus

Introduction

We investigated the performance of the cobas® 6800 system and cobas SARS-CoV-2 & Influenza A/B, a fully automated molecular testing system for influenza viruses and severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2). This enabled an assay in a batch of 96 samples in approximately 3 h.

Methods

An assay was performed using the cobas SARS-CoV-2 & Influenza A/B on the cobas 6800 system for samples collected in four facilities between November 2019 and March 2020 in our previous study. The results were compared with those obtained using the reference methods.

Results

Of the 127 samples analyzed, the cobas SARS-CoV-2 & Influenza A/B detected influenza A virus in 75 samples, of which 73 were positive using the reference methods. No false negative results were observed. The overall positive and negative percent agreement for influenza A virus detection were 100.0% and 96.3%, respectively. There were no positive results for the influenza B virus or SARS-CoV-2.

Conclusion

The cobas 6800 system and cobas SARS-CoV-2 & Influenza A/B showed high accuracy for influenza A virus detection and can be useful for clinical laboratories, especially those that routinely assay many samples.

Poor prognosis after lower‐limb amputation irrespective of diabetes status in patients undergoing hemodialysis

INTRODUCTION

Diabetes mellitus is one of the most important risk factors for lower-limb amputation in patients undergoing hemodialysis. However, the influence of diabetes mellitus on survival after lower-limb amputation is unknown.

METHODS

Patients who underwent lower-limb amputation since 1996 (amputation group) and those who underwent hemodialysis during 2011-2012 (control group) were included and were followed up until July 2022.

RESULTS

There were 70 patients (age: 66.3 ± 8.2 years, 80% male, 77% diabetic) in the amputation group and 328 (age: 67.5 ± 13.5 years, 56% male, 33% diabetic) in the control group. The amputation group showed a poorer prognosis than the control group (hazard ratio [HR]: 2.41, p < 0.001). In the control group, patients with diabetes exhibited poorer survival than those without diabetes (HR: 1.86, p < 0.001). In the amputation group, patients with diabetes exhibited improved survival (HR: 0.47, p = 0.02).

CONCLUSION

Patients undergoing hemodialysis who underwent lower-limb amputation exhibited a poor prognosis, irrespective of diabetes status.

Pan-HER inhibitors overcome lorlatinib resistance caused by NRG1/HER3 activation in ALK-rearranged lung cancer

Lorlatinib, a third-generation anaplastic lymphoma kinase (ALK)-tyrosine kinase inhibitor (TKI) with a broad coverage against ALK mutations, has demonstrated dramatic effects in patients with ALK-rearranged lung cancer. The mechanisms of acquired resistance to lorlatinib by secondary ALK compound mutations have recently been reported; however, resistance mechanisms other than secondary mutations remain unclear. Here, we investigated the molecular mechanisms of the acquired resistance in ALK-rearranged lung cancer cells in vitro. We established two different lorlatinib-resistant ALK-rearranged lung cancer cell lines (H3122LR and A925LLR) via long-term administration of lorlatinib. These resistant cells did not harbor the secondary ALK mutations and showed cross-resistance to the other kinds of ALK-TKIs (crizotinib or alectinib) compared with the parental cells; however, these resistant cells overexpressed the phosphorylated human epidermal growth factor receptor 3 (HER3) protein and the ligand of HER3 (neuregulin 1; NRG1). Pharmacological inhibition of HER3 with pan-HER inhibitors or genetic knockdown of HER3 with siRNA resensitized H3122LR and A925LLR cells to lorlatinib in vitro, indicating that H3122LR and A925LLR acquired resistance by NRG1/HER3 activation. These findings demonstrated that targeting NRG1/HER3 is a potential novel therapeutic option for lorlatinib-resistant ALK-rearranged lung cancer.

Efficacy of Lactococcus lactis strain plasma (LC-Plasma) in easing symptoms in patients with mild COVID-19: protocol for an exploratory, multicentre, double-blinded, randomised controlled trial (PLATEAU study)

INTRODUCTION

The COVID-19 pandemic has been a major concern worldwide; however, easily accessible treatment options for patients with mild COVID-19 remain limited. Since the oral intake of Lactococcus lactis strain plasma (LC-Plasma) enhances both the innate and acquired immune systems through the activation of plasmacytoid dendritic cells (pDCs), we hypothesised that the oral intake of LC-Plasma could aid the relief or prevention of symptoms in patients with asymptomatic or mild COVID-19.

METHODS AND ANALYSIS

This is an exploratory, multicentre, double-blinded, randomised, placebo-controlled trial. This study was initiated in December 2021 and concludes in April 2023. The planned number of enrolled subjects is 100 (50 subjects×2 groups); subject enrolment will be conducted until October 2022. Patients with asymptomatic or mild COVID-19 will be enrolled and randomly assigned in a 1:1 ratio to group A (oral intake of LC-Plasma-containing capsule, 200 mg/day, for 14 days) or group B (oral intake of placebo capsule, for 14 days). The primary endpoint is the change in subjective symptoms measured by the severity score. Secondary endpoints include SARS-CoV-2 viral loads, biomarkers for pDC activation, serum SARS-CoV-2-specific antibodies, serum cytokines, interferon and interferon-inducible antiviral effectors and the proportion of subjects with emergency room visits to medical institutions or who are hospitalised.

ETHICS AND DISSEMINATION

The study protocol was approved by the Clinical Research Review Board of Nagasaki University, in accordance with the Clinical Trials Act of Japan. The study will be conducted in accordance with the Declaration of Helsinki, the Clinical Trials Act, and other current legal regulations in Japan. Written informed consent will be obtained from all the participants. The results of this study will be reported in journal publications.

TRIAL REGISTRATION NUMBER

Japan Registry of Clinical Trials (registration number: jRCTs071210097).

Two Distinct Mechanisms Underlying γδ T Cell-Mediated Regulation of Collagen Type I in Lung Fibroblasts

Idiopathic pulmonary fibrosis is a chronic intractable lung disease, leading to respiratory failure and death. Although anti-fibrotic agents delay disease progression, they are not considered curative treatments, and alternative modalities have attracted attention. We examined the effect of human γδ T cells on collagen type I in lung fibroblasts. Collagen type I was markedly reduced in a γδ T cell number-dependent manner following treatment with γδ T cells expanded with tetrakis-pivaloxymethyl 2-(thiazole-2-ylamino) ethylidene-1,1-bisphosphonate (PTA) and interleukin-2. Collagen type I levels remained unchanged on addition of γδ T cells to the culture system through a trans-well culture membrane, suggesting that cell–cell contact is essential for reducing its levels in lung fibroblasts. Re-stimulating γδ T cells with (E)-4-hydroxy-3-methylbut-2-enyl diphosphate (HMBPP) reduced collagen type I levels without cell–cell contact, indicating the existence of HMBPP-induced soluble anti-fibrotic factors in γδ T cells. Adding anti-interferon-γ (IFN-γ)-neutralizing mAb restored collagen type I levels, demonstrating that human γδ T cell-derived IFN-γ reduces collagen type I levels. Conversely, interleukin-18 augmented γδ T cell-induced suppression of collagen type I. Therefore, human γδ T cells reduce collagen levels in lung fibroblasts via two distinct mechanisms; adoptive γδ T cell transfer is potentially a new therapeutic candidate.

Clinical Differentiation of Severe Fever with Thrombocytopenia Syndrome from Japanese Spotted Fever

Severe fever with thrombocytopenia syndrome (SFTS) and Japanese spotted fever (JSF; a spotted fever group rickettsiosis) are tick-borne zoonoses that are becoming a significant public health threat in Japan and East Asia. Strategies for treatment and infection control differ between the two; therefore, initial differential diagnosis is important. We aimed to compare the clinical characteristics of SFTS and JSF based on symptomology, physical examination, laboratory data, and radiography findings at admission. This retrospective study included patients with SFTS and JSF treated at five hospitals in Nagasaki Prefecture, western Japan, between 2013 and 2020. Data from 23 patients with SFTS and 38 patients with JSF were examined for differentiating factors and were divided by 7:3 into a training cohort and a validation cohort. Decision tree analysis revealed leukopenia (white blood cell [WBC] < 4000/μL) and altered mental status as the best differentiating factors (AUC 1.000) with 100% sensitivity and 100% specificity. Using only physical examination factors, absence of skin rash and altered mental status resulted in the best differentiating factors with AUC 0.871, 71.4% sensitivity, and 90.0% specificity. When treating patients with suspected tick-borne infection, WBC < 4000/µL, absence of skin rash, and altered mental status are very useful to differentiate SFTS from JSF.

Immunosuppressive tumor microenvironment in extraskeletal myxoid chondrosarcoma: A case of pleural metastases

Extraskeletal myxoid chondrosarcoma (EMCS) is an undifferentiated mesenchymal malignancy; however, its immune microenvironment remains to be elucidated. The case of a 34-year-old woman who developed EMCS metastasizing to the pleura is presented here. The pleural EMCS showed hypervascularity, absent PD-L1 expression, and a lack of tumor mutational burden and pathogenic variants. Immunohistological examination of the pleural lesions showed predominant M2 macrophages and sparse CD8⁺ T cells. EMCS and the tumor stroma were positive for transforming growth factor-β1 (TGF-β1) and vascular endothelial growth factor (VEGF). In contrast, a small number of the stromal vessels were positive for hypoxia inducible factor-1α (HIF-1α). TGF-β1 and VEGF in the tumor stroma and low antigenicity of the tumor cells may help explain how EMCS induced the immunosuppressive microenvironment. These findings may encourage investigators to explore novel combined immunotherapy for EMCS, such as TGF-β1 and VEGF inhibitors, and specific therapy for enhancing tumor antigens.