Relationship between Respiratory Microbiome and Systemic Inflammatory Markers in COPD: A Pilot Study.

The respiratory microbiome may influence the development and progression of COPD by modulating local immune and inflammatory events. We aimed to investigate whether relative changes in respiratory bacterial abundance are also associated with systemic inflammation, and explore their relationship with the main clinical COPD phenotypes. Multiplex analysis of inflammatory markers and transcript eosinophil-related markers were analyzed on peripheral blood in a cohort of stable COPD patients (n = 72). Respiratory microbiome composition was analyzed by 16S rRNA microbial sequencing on spontaneous sputum. Spearman correlations were applied to test the relationship between the microbiome composition and systemic inflammation. The concentration of the plasma IL-8 showed an inverted correlation with the relative abundance of 17 bacterial genera in the whole COPD cohort. COPD patients categorized as eosinophilic showed positive relationships with blood eosinophil markers and inversely correlated with the degree of airway obstruction and the number of exacerbations during the previous year. COPD patients categorized as frequent exacerbators were enriched with the bacterial genera Pseudomonas which, in turn, was positively associated with the severity of airflow limitation and the prior year's exacerbation history. The associative relationships of the sputum microbiome with the severity of the disease emphasize the relevance of the interaction between the respiratory microbiota and systemic inflammation.

Differential lung gene expression identified Zscan2 and Bag6 as novel tissue repair players in an experimental COPD model.

Chronic obstructive pulmonary disease is a common chronic lung disease with an ever-increasing incidence. Despite years of drug research and approvals, we are still not able to halt progress or restore normal lung function. Our previous studies have demonstrated that liver growth factor-LGF has an effect on the repair of the affected tissue in a mouse model of cigarette smoke exposure, but by what pathways it achieves this is unknown. The present study aimed to identify differentially expressed genes between emphysematous mice treated with LGF to identify potential therapeutic targets for the treatment of pulmonary emphysema. The emphysema mouse model was induced by prolonged exposure to cigarette smoke. To determine the gene expression profile of the lung in smokers treated or not with LGF, lung messenger RNA gene expression was assessed with the Agilent Array platform. We carried out differentially expressed gene analysis, functional enrichment and validated in treated mouse lung samples. The treated group significantly improved lung function (~35%) and emphysema level (~20%), consistent with our previous published studies. Microarray analysis demonstrated 290 differentially expressed genes in total (2.0-fold over or lower expressed). Injury repair-associated genes and pathways were further enhanced in the lung of LGF treated mice. The expression trends of two genes (Zscan2 and Bag6) were different in emphysematous lungs treated with LGF compared to untreated lungs. Therefore, Zscan2 and Bag6 genes could play a role in regulating inflammation and the immune response in the lung that undergoes partial lung regeneration. However, further studies are necessary to demonstrate this causal relationship.

COPD: systemic proteomic profiles in frequent and infrequent exacerbators.

Background: Some patients with COPD suffer frequent exacerbations (FE). We hypothesised that their systemic proteomic profile would be different from that of non-frequent exacerbators (NFE). The objective of the present study was to contrast the systemic proteomic profile in FE versus NFE. As a reference, we also determined the systemic proteomic profile of healthy controls (HC) and COPD patients during an actual episode of exacerbation (AE). Methods: In the analysis we included 40 clinically stable COPD patients (20 FE and 20 NFE), and 20 HC and 10 AE patients. Their plasma samples were analysed by combining two complementary proteomic approaches: label-free liquid chromatography-tandem mass spectrometry and multiplex immunoassays. Gene Ontology annotation, pathway enrichment and network analyses were used to investigate molecular pathways associated with differentially abundant proteins/peptides (DAPs). Results: Compared with HC, we identified 40 DAPs in FE, 10 in NFE and 63 in AE. Also compared to HC, pathway functional and protein-protein network analyses revealed dysregulation of inflammatory responses involving innate and antibody-mediated immunity in COPD, particularly in the FE group, as well as during an AE episode. Besides, we only identified alterations in the complement and coagulation cascades in AE. Conclusion: There are specific plasma proteome profiles associated with FE, which are partially shared with findings observed during AE, albeit others are uniquely present during the actual episode of AE.

Sleep apnoea increases biomarkers of immune evasion, lymphangiogenesis and tumour cell aggressiveness in high-risk patients and those with established lung cancer.

Background: Intermittent hypoxaemia and obstructive sleep apnoea (OSA) have been linked to lung cancer through as yet unidentified pathophysiological mechanisms. This study evaluates the effect of OSA on serum levels of biomarkers of immunosurveillance, lymphangiogenesis and intrinsic tumour cell aggressiveness in high-risk individuals screened for lung cancer and patients with established lung cancer. Methods: Serum samples from individuals participating in a lung cancer screening cohort (SAILS study) or with newly diagnosed lung cancer (SAIL study) were analysed. All patients underwent home sleep apnoea testing. Soluble levels of programmed cell death-1 (PD-1), programmed cell death ligand-1 (PD-L1), cytotoxic T-lymphocyte antigen-4, midkine (MDK), paraspeckle component-1 (PSPC1), transforming growth factor-ß1 (TGF-ß1), SMAD3, matrix metalloproteinase-2 and co-stimulus receptor of the tumour necrosis factor family of receptors (CD137) were determined by ELISA. Results: The presence of moderate-to-severe OSA was associated with increased levels of PSPC1, MDK, PD-L1 and PD-1 in screened individuals, and with higher values of PSPC1, TGF-ß1, PD-L1 and PD-1 in patients with established lung cancer. The findings correlated with nocturnal intermittent hypoxaemia indices. Conclusion: Moderate-to-severe OSA is associated with increased expression of serum biomarkers of immune evasion, lymphangiogenesis and tumour cell aggressiveness in high-risk individuals screened for lung cancer and those with established disease.

Lung Function and Symptoms of Exposure to the Volcanic Eruption in the Canary Islands: First Follow-Up of the ASHES Study.

INTRODUCTION: Exposure to gases and particulate matter released during volcanic eruptions can prove harmful to population health. This paper reports the preliminary results of the ASHES study, aimed at ascertaining the respiratory health effects of the 2021 volcanic eruption in La Palma Island (Spain) on the adult population without previous respiratory disease. METHODS: Ambispective cohort study on the healthy adult population. Three exposure groups were considered: Group 1, high exposure; Group 2, moderate exposure; and Group 3, minor or no exposure. We carried out a descriptive analysis of symptoms during and after the eruption, as well as measure lung function after the eruption (through forced spirometry and diffusing capacity of carbon monoxide). RESULTS: The analysis included 474 subjects: 54 in Group 1, 335 in Group 2, and 85 in Group 3. A significant increase in most symptoms was observed for subjects in the groups exposed during the eruption. After the eruption, this increase remained for some symptoms. There seems to be a dose-response relationship, such that the higher the exposure, the higher the odds ratio. A prebronchodilator FEV1/FVC ratio<70% was observed in 13.0% of subjects in Group 1, 8.6% of subjects in Group 2, and 7.1% of subjects in Group 3. CONCLUSIONS: This study is the first to report a dose-response relationship between exposure to volcanic eruptions and the presence of symptoms in adults. Furthermore, there is a tendency toward obstructive impairment in individuals with higher exposure.

Triple Therapy and Clinical Control in B+ COPD Patients: A Pragmatic, Prospective, Randomized Trial.

INTRODUCTION: Treatment with LABA/LAMA is recommended in GOLD B patients. We hypothesized that triple therapy (LABA/LAMA/ICS) will be superior to LABA/LAMA in achieving and maintaining clinical control (CC), a composite outcome that considers both impact and disease stability in a subgroup of GOLD B patients (here termed GOLD B+ patients) characterized by: (1) remaining symptomatic (CAT≥10) despite regular LABA/LAMA therapy; (2) having suffered one moderate exacerbation in the previous year; and (3) having blood eosinophil counts (BEC) ≥150cells/µL. METHODS: The ANTES B+ study is a prospective, multicenter, open label, randomized, pragmatic, controlled trial designed to test this hypothesis. It will randomize 1028 B+ patients to continue with their usual LABA/LAMA combination prescribed by their attending physician or to begin fluticasone furoate (FF) 92µg/umeclidinium (UMEC) 55µg/vilanterol (VI) 22µg in a single inhaler q.d. for 12 months. The primary efficacy outcome will be the level of CC achieved. Secondary outcomes include the clinical important deterioration index (CID), annual rate of exacerbations, and FEV1. Exploratory objectives include the interaction of BEC and smoking status, all-cause mortality and proportion of patients on LABA/LAMA arm that switch therapy arms. Safety analysis include adverse events and incidence of pneumonia. RESULTS: The first patient was recruited on February 29, 2024; results are expected in the first quarter of 2026. CONCLUSIONS: The ANTES B+ study is the first to: (1) explore the efficacy and safety of triple therapy in a population of B+ COPD patients and (2) use a composite index (CC) as the primary result of a COPD trial.