Search Results (1,086)

Air pollutants can cause respiratory diseases, highlighting the need for effective preventive and therapeutic strategies. We investigated the protective effects of heat-killed Lacticaseibacillus paracasei ATG-E1 against particulate matter plus diesel exhaust particle (PM₁₀D)-induced airway inflammation. BALB/c mice were intranasally injected with PM₁₀D and treated with heat-killed L. paracasei ATG-E1 via oral gavage for 5 days. In the bronchoalveolar lavage fluid (BALF) and lungs, inflammatory mediators, immune cell subtypes, and histological changes were analyzed, while gut microbiota composition was analyzed in the cecum. Heat-killed L. paracasei ATG-E1 suppressed the infiltration of immune cells, including neutrophils, T cells, and B cells. Furthermore, it decreased various inflammatory mediators, such as C-X-C Motif chemokine ligand (CXCL)-1, macrophage inflammatory protein (MIP)-2, interleukin (IL)-1α, and tumor necrosis factor (TNF)-α, in the BALF and lung tissue, as well as serum symmetric dimethylarginine (SDMA) levels in the PM₁₀D-induced airway inflammation model. Heat-killed L. paracasei ATG-E1 also exhibited a protective effect against lung damage induced by PM₁₀D. Furthermore, heat-killed L. paracasei ATG-E1 treatment shifted the gut microbiota composition, increasing several bacterial genera. The data demonstrate that heat-killed L. paracasei ATG-E1 acts as a protective agent against air pollutant-induced lung injury, suggesting its potential as a candidate adjunctive strategy for prevention. Full article

Background/Objectives: Bulk RNA sequencing (RNA-seq) averages signals across heterogeneous cell populations. Computational deconvolution methods aim to infer cell type composition and cell type-specific gene expression from bulk data, but their performance in equine samples has not been evaluated. In this study, we assessed the ability of computational deconvolution to recover cellular composition and differential expression signals in bronchoalveolar lavage fluid (BALF) from horses with severe equine asthma (SEA) and controls (CTL). Methods: Cryopreserved BALF samples from six SEA and five CTL horses previously analyzed by scRNA-seq were used to generate bulk RNA-seq data. The matched scRNA-seq dataset served as the reference for deconvolution. Performance was evaluated by comparing deconvolution raw and mRNA-corrected estimates with scRNA-seq cell proportions. Differential expression between SEA and CTL was analyzed on bulk RNA-seq, deconvoluted expression profiles, and scRNA-seq pseudobulk data. Results: Deconvolution primarily captured mRNA-derived cell type proportions rather than true cell counts: agreement with scRNA-seq cell counts was moderate (r = 0.62; 95% CI 0.45–0.75) but improved after mRNA content correction (r = 0.83; 95% CI 0.74–0.89). Comparison with mRNA-weighted scRNA-seq proportions showed near-perfect concordance (r = 0.98; 95% CI 0.97–0.99). Cell type-specific performance varied, with stronger correlations for B cells and dendritic cells and weaker performance for neutrophils, T cells and monocytes/macrophages. Recovery of cell type-specific differential expression was inconsistent, frequently showing cross-lineage signal spillover. Although both approaches detected a Th17 signature in SEA, most deconvolution-derived differentially expressed genes overlapped with conventional bulk RNA-seq results. Conclusions: Deconvolution of bulk RNA-seq did not reliably estimate cell counts or provide substantial biological insight beyond conventional bulk analysis, highlighting the value of scRNA-seq for resolving cell type-specific disease mechanisms in equine asthma. Full article

Interleukin-22 binding protein (IL-22BP) is a soluble decoy receptor that competitively inhibits IL-22 by preventing its interaction with the IL-22 receptor. Although the IL-22 receptor is primarily expressed on non-hematopoietic cells, such as airway epithelial cells, the role of IL-22BP in the pathogenesis of asthma remains uncertain. We observed that IL-22BP was upregulated in the airways of wild-type (WT) mice intranasally sensitized and challenged with house dust mite (HDM) extract. To directly elucidate the function of IL-22BP in allergic airway responses, IL-22BP-deficient (IL-22BP−/−) and WT mice were sensitized and challenged with HDM, and airway responses were systematically assessed. IL-22BP−/− mice exhibited significantly lower airway hyperresponsiveness (AHR) compared to WT mice following sensitization and challenge with HDM. In contrast, eosinophil counts in bronchoalveolar lavage (BAL) fluid did not differ significantly between the two groups. Similarly, levels of interleukin (IL)-4, IL-5, IL-6, IL-13, IL-17A, and keratinocyte chemoattractant (KC) in BAL fluid were comparable between WT and IL-22BP−/− mice. Notably, IL-22 levels in lung homogenates were significantly higher in IL-22BP−/− mice than in WT mice after sensitization and challenge with HDM. These findings suggest that inhibition of IL-22BP attenuates the development of allergen-induced AHR, an effect likely mediated through enhanced IL-22 activity rather than alterations in airway inflammation or type 2 cytokine production. Full article

Background: Diphtheria is an acute infectious disease caused by Corynebacterium diphtheriae. Despite several worldwide outbreaks, it is now considered a rare disease by industrialized countries. Clinical manifestations usually account for oropharyngeal lesions, but rare cases of systemic involvement (mainly endocarditis) have been described among non-toxigenic strains. Case description: We report the case of a patient who experienced septic shock, disseminated intravascular coagulation and multiorgan failure due to Corynebacterium diphtheriae infection. The pathogen was further characterized as a highly toxigenic strain. Infective endocarditis with mitral and aortic valve vegetations led to early multiorgan septic embolization. Major stroke, liver function impairment, heart failure and acute kidney injury were the main findings. Unlike the typical forms of infection caused by this pathogen, there was no evidence of airway or skin involvement. Furthermore, apart from hemocultures, none of the other investigations (pharyngeal swabs, bronchoalveolar lavages, urine culture) ever tested positive for the bacteria. Conclusions: The report we present describes a case of C. diphtheriae infection with many atypical characteristics: (i) lack of any pathognomonic signs or symptoms; (ii) extensive endocarditic process (very uncommon for toxigenic strains); (iii) early septic emboli development, with rapid evolution to multiorgan failure; (iv) detection of disseminated intravascular coagulation. Despite disseminated intravascular coagulation being a known complication of septic shock, regardless of the etiological agent, according to our literature research, this is the second known case driven by C. diphtheriae infection in an adult. Full article

The use of inhaled corticosteroids (ICs) could influence the respiratory microbiota. In animals with asthma it is, however, difficult to separate the immunomodulatory effects of ICs from their indirect effects via improvement of ventilation. Our objective was to determine if ICs alter the pulmonary microbiota independently from their effects on lung function, using a blinded, controlled trial in an experimental model of asthma exacerbation in horses. We treated horses with severe asthma with either bronchodilators alone, or in combination with ICs. Twelve horses in exacerbation received long-acting β2-agonist (LABA, salmeterol) or ICs/LABA (fluticasone/salmeterol) by inhalation, for 2 weeks. Lung function and bronchoalveolar lavages (BAL) were performed before and after treatment. 16S rRNA gene quantification and sequencing were performed on BAL fluid, using digital droplet PCR and the Illumina MiSeq platform. Data were processed using the software package mothur v. 1.44.2. In the LABA group, pulmonary bacterial load and the relative abundance of Actinobacteria and Verrucomicrobia phyla decreased with treatment (p < 0.05 for both), and β-diversity differed from baseline (p = 0.007). The relative abundance of families and genera belonging to the Bacteroidetes phylum increased with ICs/LABA (p < 0.05). Lung function significantly improved with both treatments, suggesting that treatment-related differences in pulmonary microbiota could be attributed in part to medication, not solely to change in ventilation. However, it is not clear if these changes are positive or detrimental to the lung environment. Furthermore, lung function following treatment was not perfectly identical between groups. Full article

Objectives: Inflammatory bowel disease (IBD) is associated with extraintestinal comorbidities, and lung diseases are widespread manifestations. Respiratory bacterial insult is a common illness that results in acute lung injury (ALI) in critical patients. IBD concurrence with respiratory infection may further exacerbate lung injury. Tryptophan (Try), an essential amino acid, is processed by gut microbiota and produces aryl hydrocarbon receptor (AhR) ligands. These ligands can activate the AhR pathway that exerts anti-inflammatory properties and provides protection against mucosal barrier injury. This study investigated the effects of dietary Try on lipopolysaccharide (LPS)-stimulated ALI in mice with colitis induced by dextran sodium sulfate (DSS). Methods: Mice with colitis were allocated to four groups: (1) ND-Sal: normal diet + DSS + intratracheal saline injection; (2) ND-LPS: normal diet + DSS + intratracheal LPS injection; (3) TD-Sal: Try diet + DSS + intratracheal saline injection; (4) TD-LPS: Try diet + DSS + intratracheal LPS injection. Mice were sacrificed 24 h after the intratracheal injection. Results: Results showed that colitis resulted in a high disease activity index. Following induction of ALI in colitis mice, neutrophil populations and inflammatory cytokine levels in bronchoalveolar lavage fluid increased. Gene expression levels associated with toll-like receptor (TLR)4/nuclear factor (NF)-κB signaling were upregulated, and tight junction proteins decreased in the lungs. Dietary Try supplementation decreased circulating LPS levels, suppressed pulmonary TLR4/NF-κB signaling, upregulated AhR/interleukin-22 expression, attenuated oxidative stress and improved the capillary–epithelial barrier integrity in DSS-treated mice. Conclusions: These findings imply that Try may have potential therapeutic significance in bacterial-induced ALI in a colitis condition. Full article

Background: Solriamfetol, a dopamine and norepinephrine reuptake inhibitor widely used in narcolepsy management, has not been thoroughly investigated for its anti-fibrotic and anti-inflammatory properties. Herein, we investigated its potential therapeutic applications and underlying mechanisms in both cellular and murine models of pulmonary fibrosis. Methods: To induce fibrosis, C57BL/6 male mice (six-week-old) were administered bleomycin via the intratracheal route. These animals subsequently received solriamfetol orally once per day at dosages of 3 or 10 mg/kg. Histological and immunohistochemical techniques were employed to evaluate inflammatory cell infiltration, collagen accumulation, and α-smooth muscle actin (α-SMA) expression in bronchoalveolar lavage samples and lung tissue sections. Cytokine levels were measured by ELISA, and gene/protein expression of pro-fibrotic markers, A_2A/A_2B adenosine receptors (ARs), adenylate cyclases (ACs), Epac, K_Ca3.1, and adenosine deaminase (ADA) were assessed via quantitative PCR and Western blot. Electrophysiological recordings evaluated K_Ca3.1 channel activity. Purified ADA and normal human lung fibroblasts (NHLFs) were treated with solriamfetol to assess effects on ADA activity and levels of cAMP and adenosine, respectively. Results: Solriamfetol significantly reduced inflammatory cell infiltration, collagen accumulation, and α-SMA expression in fibrotic lungs. Solriamfetol restored downregulated A_2AAR, A_2BAR, ACs, and Epac, while suppressing ADA expression and activity, resulting in elevated extracellular adenosine and intracellular cAMP. The intervention potentiated Epac signaling and inhibited fibroblast activation. Solriamfetol inhibited the K_Ca3.1 current in fibroblasts and reduced K_Ca3.1 protein expression levels in TGFβ-treated fibroblasts and lung tissues from bleomycin-challenged mice. Notably, these effects were abolished by A_2AAR or A_2BAR antagonists, implying that they occur through AR-mediated pathways. Conclusions: Solriamfetol inhibits ADA and reinforces adenosine–cAMP signaling, suppressing pathological fibroblast activation. These findings suggest its therapeutic utility as a novel anti-fibrotic compound for various fibrotic diseases, including pulmonary fibrosis. Full article

Background: Systemic autoimmune rheumatic diseases-associated interstitial lung disease (SARD-ILD) presents with varied disease courses, emphasizing the need for reliable predictors of progression. The prognostic utility of bronchoalveolar lavage (BAL) in SARD-ILD remains underexplored. The objective of this study was to evaluate the role of BAL fluid lymphocyte count in predicting disease progression in patients with SARD-ILD. Methods: This observational study included patients with SARD-ILD undergoing BAL as part of their diagnostic workup. Disease progression was defined as either Forced vital capacity (FVC) decrease >10%, two out of the following three criteria within two years: FVC decrease of 5–10%, worsening symptoms, increased fibrosis on imaging, or any of the following: escalation of treatment, Interstitial lung disease (ILD) exacerbation, lung transplantation, or disease-specific mortality. Logistic regression identified predictors of progression. Time-to-progression was assessed using Kaplan–Meier survival curves. The optimal BAL lymphocyte threshold for predicting progression was identified using the Youden Index and the Wilcoxon method. Results: We identified 89 patients, of whom 30 (33.7%) had progressive disease. Progressors had a significantly higher BAL lymphocyte count compared to non-progressors (31.6 ± 24.8% vs. 14.3 ± 16.5%, p < 0.001). BAL lymphocyte proportion was significantly and independently associated with disease progression (odds ratio, 1.05; 95% confidence interval 1.02–1.07; p < 0.01). A lymphocyte count above 9 percent was associated with a markedly increased risk of disease progression (odds ratio, 13.14; 95% confidence interval, 4.20–51.98; p < 0.01). Conclusions: BAL lymphocyte count was associated with a higher likelihood of progression in SARD-ILD. BAL assessment may help identify patients at increased risk of disease progression. However, these findings should be considered exploratory and require validation in larger prospective studies and across individual SARD-ILD subtypes. Full article

Background: Flexible bronchoscopy (FB) has long been integral to pulmonology, but its bedside role in the intensive care unit (ICU) is expanding. Despite a lack of high-level evidence, FB remains a pivotal tool for airway visualization, sampling, and selected interventions in critically ill patients. Objective: This meta-narrative review critically appraises the clinical use, evolving indications, safety profile, and emerging controversies of FB in ICU settings, particularly regarding the role of non-pulmonologist intensivists. Methods: A structured literature search was conducted using PubMed, Scopus, and Google Scholar for studies published in the past 15 years. Emphasis was placed on observational studies, meta-analyses, and guidelines relevant to FB in ICU patients. Key controversies were grouped under thematic questions based on clinical relevance. Results: A total of 84 articles were retrieved, of which 47 met the predefined inclusion criteria. Seven key thematic domains were synthesized regarding the use of flexible bronchoscopy (FB) in the intensive care unit (ICU) setting. FB performed by trained intensivists was found to be safe and diagnostically effective across a range of ICU populations, including elderly and non-intubated patients. Although procedure-related hypoxemia was reported, it was largely manageable with appropriate precautions. FB demonstrated critical utility in the management of acute respiratory failure (ARF), acute respiratory distress syndrome (ARDS), and sepsis, particularly through bronchoalveolar lavage (BAL), airway secretion clearance, and, selectively, bronchoscopic lung biopsy. The adoption of disposable bronchoscopes may reduce infection risk and economic burden. Furthermore, the integration of advanced techniques such as endobronchial ultrasound (EBUS) and transbronchial cryobiopsy is emerging, although application in the critical care environment remains cautious and selective. Conclusions: With structured training and careful patient selection, FB is an adaptable and often underutilized tool in ICU medicine. Multidisciplinary competency development and institutional protocols can enhance its safe integration. Full article

Pneumocystis is an opportunistic fungal pathogen that causes severe Pneumocystis pneumonia (PCP) in immunocompromised individuals and laboratory animals. Three host-specific species—Pneumocystis murina (P. murina), Pneumocystis carinii (P. carinii), and Pneumocystis jirovecii (P. jirovecii)—are closely associated with infections in humans and laboratory animals. However, the conventional method, microscopic staining, suffers from low sensitivity, operator-dependent subjectivity, and inability to differentiate species, highlighting the urgent need for a multiplex qPCR assay. In this study, we established a multiplex qPCR method targeting the mtLSUrRNA gene of P. murina, the TS gene of P. carinii, and the mtSSUrRNA gene of P. jirovecii. Primers and probes were designed and optimized using a matrix approach. The method was systematically evaluated for sensitivity, specificity, and reproducibility using recombinant plasmid standards and laboratory animal samples. Validation was performed on 260 mouse lung samples, 30 P. murina-positive samples, 25 rat lung samples, 6 rat bronchoalveolar lavage fluid (BALF) samples, and 8 P. carinii-positive samples. Results were compared with single-plex qPCR and staining microscopy (performed on 68 mouse lung samples, 38 Pneumocystis-positive samples). The limits of detection (LOD) were 5 copies/μL for P. murina, 6 copies/μL for P. carinii, and 8 copies/μL for P. jirovecii. Standard curves showed excellent linearity (R² ≥ 0.999) with amplification efficiencies of 90–110%. No non-specific reactions were observed with 22 common pathogens, and intra-/inter-group coefficients of variation (CV%) were below 1%. Moreover, interference testing revealed minimal matrix effects on the amplification system and no mutual interference among the primers and probes. The multiplex qPCR detected all 38 positive samples (100%), showing 100% concordance with single-plex qPCR, whereas Giemsa staining detected none (0%) and toluidine blue staining only 60% (3/5) of the tested positives, suggesting that the multiplex qPCR achieved higher detection rates than staining microscopy. In conclusion, this novel multiplex qPCR method offers high sensitivity, specificity, and reproducibility, providing a sensitive and specific tool for laboratory animal health monitoring and epidemiological surveillance. Its clinical application for human PCP diagnosis requires further validation with authentic human specimens. Full article

Background: Pulmonary tuberculosis (TB) is a significant trigger of acute exacerbations of chronic obstructive pulmonary disease (AECOPD), so its timely and accurate diagnosis is essential. Also, the risk factors for TB occurrence in this population remain unclear. This study aimed to evaluate the performance of metagenomic next-generation sequencing (mNGS) for TB diagnosis in AECOPD patients, as well as to identify the associated risk factors. Methods: A retrospective observational cohort of 659 AECOPD patients with suspected pulmonary infection was enrolled. The microbial cell-free nucleic acids in bronchoalveolar lavage fluid samples were extracted and subjected to mNGS detection. The clinical data for each patient were collected from the hospital information system. The statistical analyses were performed with SPSS version 25.0. Results: A total of 170 cases, included for final analyses, were categorized into TB (n = 41), bacterial infection (n = 73), and non-infective control (n = 56) groups. Among these groups, the TB group had the highest intensive care unit (ICU) admission rate (46.34%) and longest median hospital stay (19.50 days) (p < 0.01). For TB diagnosis, mNGS demonstrated a greater sensitivity (86.00%), a lower specificity (93.30%), and a higher area under the curve (AUC, 0.877) than TB-DNA detection (70.21%, 100%, 0.848, respectively) and Xpert Mycobacterium tuberculosis/rifampicin (MTB/RIF) assay (63.83%, 100.00%, 0.870, respectively). Notably, mNGS identified the bacterial or viral co-infections in 18.00% of TB cases. Furthermore, the stringently mapped read number determined by mNGS showed a positive correlation with ICU admission rate (r = 0.76) and in-hospital mortality (r = 0.77). The lower body mass index (BMI) and reduced natural killer (NK) cell count were identified as the independent risk factors in the TB group (both p < 0.05). Conclusions: For the diagnosis of pulmonary TB in AECOPD patients, mNGS demonstrated comparable performance to TB-DNA detection and Xpert MTB/RIF assay, and also mNGS identified co-infections. In addition, a lower BMI and reduced NK cell count were identified as the independent risk factors for TB occurrence in this cohort. Full article

Background: Magnetic particle imaging (MPI) is an emerging, tracer-based modality that directly detects superparamagnetic iron oxide nanoparticles (SPIONs) with exceptional sensitivity, quantitative signal behavior, and full immunity to air–tissue susceptibility artifacts. These features make MPI particularly well-suited for pulmonary imaging, where traditional techniques such as computed tomography (CT), magnetic resonance imaging (MRI), and nuclear medicine-based ventilation/perfusion (V/Q) imaging are limited by radiation exposure, low contrast, and motion-related signal degradation. Objective: This review synthesizes the current state of MPI for lung imaging, with emphasis on its physical principles, tracer development, preclinical applications, and its potential role in assessing pulmonary perfusion, vascular integrity, inflammation, and therapeutic responses. Methods: A systematic evaluation of preclinical studies was performed across three major application domains: pulmonary perfusion mapping, cell tracking and therapeutic monitoring, and vascular injury and permeability assessment. Study designs, SPION formulations, MPI acquisition strategies, and validation methods, including histopathology, biodistribution, broncho-alveolar lavage fluid (BALF) analysis, and Evans Blue assays, were examined to characterize methodological consistency and imaging performance. Results: MPI consistently demonstrated high-contrast, quantitative visualization of pulmonary blood flow, endothelial barrier disruption, inflammatory signaling, and transplanted or inhaled cell populations. Tracer engineering played a critical role: macroaggregated albumin superparamagnetic iron oxide nanoparticles (MAA-SPIONs) enabled capillary-level perfusion mapping, LS-008 improved temporal resolution and vascular delineation, Synomag/Synomag-D allowed quantification of vascular leakage in acute and chronic lung injury, and vascular cell adhesion molecule-1 (VCAM-1)-targeted probes provided molecular-level assessment of inflammation. Hybrid MPI-CT and MPI-MRI approaches further enhanced anatomic localization and enabled accurate pulmonary blood volume (PBV) estimation. Across studies, MPI measurements showed strong agreement with established biological assays and remained free of the artifacts that limit CT and MRI in the lung. Conclusions: Preclinical evidence demonstrates that MPI is a robust, radiation-free, and quantitatively precise modality for functional and molecular lung imaging. Its ability to map perfusion, track therapeutic agents, and noninvasively quantify vascular permeability positions MPI as a promising future alternative or complement to CT, MRI, and nuclear medicine for pulmonary assessment. Continued tracer optimization, system scaling, and clinical validation are key steps toward translating MPI into routine clinical use. Full article

Background/Objectives: Bleomycin is an antineoplastic antibiotic used in the management of various malignancies. Nevertheless, its benefits are constrained by the development of pulmonary fibrosis. Amentoflavone, a biflavonoid, exhibits diverse pharmacological activities, including anti-inflammatory, antiviral, antioxidant, and antitumor effects, whereas alogliptin possesses antioxidant and anti-inflammatory properties. This study aimed to assess the potential protective effects of alogliptin and/or amentoflavone in a murine model of bleomycin-induced pulmonary fibrosis and to clarify the underlying mechanisms. Methods: Fifty male C57BL/6 mice were randomly divided into 5 equal groups: control, bleomycin, bleomycin + alogliptin, bleomycin + amentoflavone, and bleomycin + alogliptin + amentoflavone. The assessed endpoints included lung weight/body weight index, lung tissue fibrotic mediators, oxidative stress parameters, proinflammatory cytokines, and pyroptotic and autophagy mediators. Also, the bronchoalveolar lavage fluid (BALF) was evaluated for total and differential leukocytic counts and lactate dehydrogenase (LDH) activity. Moreover, vascular responses to potassium chloride, phenylephrine, and carbachol, together with tracheal responses to carbachol were determined. Lung tissues were further examined histopathologically and immunohistochemically. Results: Treatment with alogliptin and/or amentoflavone significantly decreased the lung weight/body weight index and BALF LDH activity, concomitant with mitigation of lung tissue oxidative stress parameters, fibrotic mediators, apoptosis, and pyroptosis with a significant augmentation of autophagy signals, alongside marked improvement in the lung architecture and vascular and airway reactivity compared with the bleomycin group. These effects were most pronounced with animals treated with the alogliptin/amentoflavone combination. Conclusions: These findings suggest that combined alogliptin and amentoflavone may constitute a promising strategy to prevent bleomycin-induced lung fibrosis. Full article

Highly pathogenic avian influenza A (H7N9) remains a threat to poultry health and poses a zoonotic risk, highlighting the need for vaccine antigens capable of inducing both systemic and mucosal immunity. In this study, we evaluated X33CLS-H7, a clarified cell-lysate supernatant derived from glycoengineered Pichia pastoris expressing H7 hemagglutinin, in BALB/c mice following intramuscular(i.m.) injection, nebulized inhalation, or intranasal instillation. H7 expression and hemagglutination activity were confirmed by Western blotting and hemagglutination assay, respectively. Serum HA7-specific IgG and IgA responses, hemagglutination inhibition(HI) activity, H7N9 pseudovirus neutralization, bronchoalveolar lavage fluid (BALF) antibodies, and safety readouts were assessed. After two i.m. immunizations, X33CLS-H7 induced the strongest systemic antibody responses, with an HI geometric mean titer of 1:1622 95% CI, 1:1108–1:2348 and a mean log10 NT₅₀ of 4.62. Respiratory immunization also elicited antibody responses. After four doses, high-dose nebulized delivery produced the strongest responses among the respiratory delivery regimens, with serum IgG and IgA titers of 1.02 × 10⁵ and 2.24 × 10³, respectively, an endpoint HI GMT r of 1:457 95% CI, 1:211–1:971, and a mean log10 NT₅₀ of 3.77 compared with 2.02 in saline controls. High-dose nebulized delivery also generated detectable HA7-specific IgG and IgA responses in bronchoalveolar lavage fluid. No overt local or systemic toxicity signals were observed under the tested conditions. These findings indicate that X33CLS-H7 retains HA7-associated antigenicity and can induce systemic and respiratory mucosal antibody responses, supporting its further evaluation as a simplified and scalable H7N9 vaccine antigen candidate. Full article

Background: Cytokine storm-like inflammation includes an imbalanced immune response, where excessive interleukin-6 (IL-6) and inadequate IL-10 play a central role in increasing tissue injury. Melaleuca cajuputi leaves are known to contain anti-inflammatory bioactive compounds. However, the potential to modulate the dysregulated cytokine response remains underexplored. Objective: This study aimed to evaluate the immunomodulatory effects of Melaleuca cajuputi subsp. cajuputi Powell Ethanolic Leaf Extract (MC-ELE) on IL-6, IL-6R, and IL-10 levels in a BALB/c mouse model of lung inflammation induced by lipopolysaccharide (LPS). Methods: Phytochemical screening was performed to identify active constituents in MC-ELE. Male BALB/c mice were intratracheally challenged with LPS (mg·kg⁻¹ BW) to induce cytokine storm-like inflammation. After 24 h, mice received oral MC-ELE at doses of 750, 1500, 3000 mg·kg⁻¹ BW, or dexamethasone (10 mg·kg⁻¹ BW), for seven consecutive days. On day eight, serum and bronchoalveolar lavage fluid (BALF) were collected for IL-6, IL-6R, and IL-10 assessment using ELISA. Furthermore, body weight changes and clinical symptoms were monitored throughout the study. Results: MC-ELE was confirmed to contain anti-inflammatory compounds. Across all groups, IL-6 concentrations in BALF were consistently higher than in serum, with the LPS-only group showing the greatest elevation. Serum IL-6R levels exceeded BALF IL-6R levels in most groups, except at 1500 mg·kg⁻¹ BW MC-ELE dose. BALF IL-10 was higher compared with serum in all MC-ELE-treated groups. Therefore, MC-ELE might preferentially enhance anti-inflammatory responses within the pulmonary microenvironment. There was no observed toxicity or weight loss at doses up to 3000 mg·kg⁻¹ BW. Conclusions: MC-ELE reported promising immunomodulatory activity by lowering IL-6 and IL-6R levels while enhancing IL-10 responses in lung inflammation induced by LPS within lung tissue. These results suggested its potential as a natural therapeutic candidate for managing severe inflammatory conditions. Full article