Flavonoids derived from licorice suppress LPS-induced acute lung injury in mice by inhibiting the cGAS-STING signaling pathway

In recent years, we have found that the dysregulation of the cyclic-GMP-AMP synthase (cGAS)‒stimulator of interferon genes (STING) pathway leads to the development of immune and inflammatory diseases, therefore, finding compounds that can specifically regulate this pathway is essential for effective regulation of the immune pathway for addressing inflammatory diseases. Licorice flavonoids (LFs), are active ingredients extracted from the Chinese herb licorice, which has been reported to have strong anti-inflammatory activity in previous studies. Here, we report that LFs inhibit the activation of the cGAS-STING pathway evidenced by the inhibition of the expression of type I interferons and related downstream genes such as interferon-stimulated gene 15 (ISG15) and C-X-C motif chemokine ligand 10 (CXCL10), as well as inflammatory cytokines such as interleukin-6 (IL-6) and tumor necrosis factor-α (TNF-α). Notably, LFs markedly improve the LPS-induced acute lung injury by inhibiting the excessive activation of cGAS-STING signaling pathway. Mechanistically, LFs treatment leads to the blocking of 2'3'-cyclic GMP-AMP (cGAMP) synthesis resulting in an inhibition of the activation of the cGAS-STING pathway. Our results indicate that LFs is a specific inhibitor of the cGAS-STING pathway, which is suggested to be a potential candidate for the treatment of cGAS-STING pathway-mediated inflammatory diseases.

Evaluation of the EUROIMMUN Aspergillus antigen immunoenzyme assay in serum and bronchoalveolar lavage fluid samples

INTRODUCTION

The most widely used marker for the diagnosis of invasive aspergillosis (IA) is the detection of galactomannan by ELISA. This study describes the evaluation of the results obtained by Euroimmun Aspergillus antigen ELISA (EIA-GM-E) in serum samples and bronchoalveolar lavage fluid (BAL) from patients at risk of IA, and compares these results with those obtained by Bio-Rad Galactomannan EIA (EIA-GM-BR).

METHODS

Anonymous retrospective case-control comparative study in 64 serum samples and 28 BAL from 51 patients.

RESULTS

Overall agreement of the results of the two assays was observed in 72 of 92 samples (78.3%). The sensitivity of EIA-GM-BR and EIA-GM-E in serum samples was 88.9% and 43.2%, respectively, and 100% and 88.9% for BAL. The specificity of EIA-GM-BR and EIA-GM-E in serum samples was 91.9% for both assays, and 68.4% and 84.2% in BAL. There were no statistically significant differences in the results of both assays.

CONCLUSIONS

Both methods show good results for the discrimination of patients with IA when BAL is tested, or serum in case of EIA-GM-BR.

Fibrinogen on extracellular vesicles derived from polyhexamethylene guanidine phosphate-exposed mice induces inflammatory effects via integrin β

Polyhexamethylene guanidine phosphate (PHMG-p), used as a humidifier disinfectant, causes interstitial lung disease, obliterative bronchiolitis, and lung fibrosis; however, little is known about its effect on intercellular interactions. Extracellular vesicles (EVs), which carry diverse compounds including proteins, RNA, and DNA to mediate cell-to-cell communication through their paracrine effects, have been highlighted as novel factors in lung fibrogenesis. This study aimed to identify the effect of proteins on small EVs (sEVs) from bronchoalveolar lavage fluid (BALF) of the recipient cells after PHMG-p exposure. A week after intratracheal administration of PHMG-p, sEVs were isolated from BALF of tissue showing overexpressed inflammatory and fibrosis markers. To investigate the role of sEVs in inflammation, naïve macrophages were cultured with sEVs, which induced their activation. To identify sEV proteins that are associated with these responses, proteomics analysis was performed. In the gene ontology analysis, coagulation, fibrinolysis, and hemostasis were associated with the upregulated proteins in sEVs. The highest increase was observed in fibrinogen levels, which was also related to those gene ontologies. We validated role of exosomal fibrinogen in inflammation using recombinant fibrinogen and an inhibitor of the integrin, which is the binding receptor for fibrinogen. Overall, we elucidated that increased fibrinogen levels in the early sEVs-PHMG activated inflammatory response during early fibrosis. These results suggest that sEVs from the BALF of PHMG-p-exposed mice could aggravate fibrogenesis by activating naïve macrophages via various proteins in the sEVs, Furthermore, this finding will be broadening the spectrum of communicating mediators.

Metabolic landscape dysregulation in bronchoalveolar lavage fluid of checkpoint inhibitor pneumonitis

BACKGROUND

Checkpoint inhibitor pneumonitis (CIP) is a potentially fatal adverse event resulting from immunotherapy in patients with malignant tumors. However, the pathogenesis of CIP remains poorly understood.

METHODS

We collected bronchoalveolar lavage fluid (BALF) from cohorts of patients with CIP, new-onset lung cancer (LC), and idiopathic pulmonary fibrosis (IPF). Non-targeted metabolomics analysis was conducted to analyze metabolic signatures. Flow cytometry was used to evaluate immune cell subsets.

RESULTS

Lymphocytes were predominant in the BALF of patients with CIP. A total of 903 metabolites were identified, among which lipid compounds were the most abundant. In a comparison between patients with CIP and LC, enrichment analysis of the altered metabolites showed suppressed amino sugar metabolism, and spermidine and spermine biosynthesis in the CIP group. Metabolism of alpha linolenic acid, linoleic acid, and their fatty acid derivatives was enriched in the CIP group relative to the IPF group. The twelve metabolites found to be enriched in the CIP group were positively correlated with the proportion of CD8⁺ T cells. One cluster of BALF metabolites, 57.14% of which were lipid molecules, was inversely correlated with the proportion of natural killer cells.

CONCLUSIONS

In this study, the metabolomic landscape of BALF in patients with CIP was determined. We elucidated suppressed tumor metabolic signatures, enhanced pulmonary inflammatory signaling, and the characteristics of responsible immune cells, which helps to understand the pathogenesis of CIP.

Effect of TLR3/dsRNA complex inhibitor on Poly(I:C)-induced airway inflammation in Swiss albino mice

Rhinovirus infection frequently causes COPD and asthma exacerbations. Impaired anti-viral signaling and reduced viral clearance have both been seen in sick bronchial epithelium, potentially increasing exacerbations. Polyinosinic:polycytidylic acid (Poly(I:C)), a Toll-like receptor-3 (TLR3) ligand, has been shown to cause a viral exacerbation of severe asthma by detecting double-stranded RNA (dsRNA). The purpose of this work was to determine the effect of a TLR3/dsRNA complex inhibitor-Calbiochem drug in the prevention of Poly(I:C)-induced airway inflammation following TLR3 activation and to uncover a potential pathway for the cure of asthma through TLR3 inhibition. Mice were sensitized with Poly(I:C) as an asthma model before being challenged by PBS and ovalbumin (OVA) chemicals. The mice were administered a TLR3/dsRNA complex inhibitor. Throughout the trial, the mice's body weight was measured after each dosage. Biochemical methods are used to analyze the protein as well as enzyme composition in airway tissues. BALF specimens are stained using Giemsa to identify inflammatory cells and lung histopathology to determine morphological abnormalities in lung tissues. By using the ELISA approach, cytokine levels such as TNF-α, IL-13, IL-6, IL-5, and IgE antibody expression in lung tissue and blood serum were assessed. TLR3/dsRNA complex inhibitor drug significantly lowered the number of cells in BALF and also on Giemsa staining slides. It also downregulated the level of TNF-α and IL-6 in contrast to OVA and Poly(I:C) administered in animals. A TLR3/dsRNA complex inhibitor decreased the fraction of oxidative stress markers (MDA, GSH, GPx, and CAT) in lung tissues while keeping the mice's body weight constant during the treatment period. By decreasing alveoli, bronchial narrowing, smooth muscle hypertrophy, and granulocyte levels, the TLR3/dsRNA complex blocker significantly reduced the histopathological damage caused by OVA and Poly(I:C) compounds. In an animal model utilizing ovalbumin, TLR3/dsRNA complex inhibitors similarly reduced the bronchial damage produced by Poly(I:C). A novel TLR3/dsRNA complex inhibitor is expected to be employed in clinical studies since it suppresses airway inflammation without inducing antiviral approach resistance.

Diagnosis by metagenomic next-generation sequencing of invasive pulmonary aspergillosis in an infant with chronic granulomatous disease

Invasive pulmonary aspergillosis (IPA) is a serious fungal infection, with a high degree of mortality in immunocompromised individuals. Diagnosis of IPA is challenging in that clinical manifestations are not specific, with sensitivity of traditional detection procedures low. We report a case of IPA in a chronic granulomatous disease (CGD) infant who was initially suspected to have a lung tumor. Aspergillus fumigatus was identified as the pathogen in bronchoalveolar lavage fluid (BALF) by next-generation sequencing (mNGS). The patient recovered rapidly following a change of appropriate antifungal treatment and was discharged. This case highlights the additional value of BALF-mNGS for the diagnosis of pediatric invasive pulmonary fungal infection in immune-deficient children.

Analysis of lymphocyte profile in lymph nodes, bronchoalveolar lavage fluid and peripheral blood in patients with stage II sarcoidosis

OBJECTIVE

To evaluate the lymphocyte profile (LP) in lymph node puncture fluid (LNPF) of mediastinal and hilar lymph nodes, bronchoalveolar lavage fluid (BALF), and peripheral blood (PB) involved in stage 2 sarcoidosis.

METHODS

After selection, 31 patients diagnosed with stage II sarcoidosis were finally included. Patients were further divided into symptomatic (n = 17) and asymptomatic (n = 14) groups according to the presence or absence of respiratory symptoms. The LP in lymph node puncture fluid (LNPF), bronchoalveolar lavage fluid (BALF), and peripheral blood (PB) were evaluated and compared using flow cytometry. The relationship between respiratory symptoms and LP was preliminarily analyzed.

RESULTS

The proportions of T cells and CD4 T cells, and CD4/CD8 ratio in BALF were significantly higher than that of LNPF with PB (all P < 0.05). The proportions of lymphocyte cells, CD8 T cells, NK cells, and CD4/CD8 ratio in LNPF and PB were significantly different (all P < 0.05). There were significant differences in CD4 T cells [72.40 (68.90,75.55) vs.46.30 (38.55,52.50), P = 0.004], CD8 T cells (9.9 ± 3.9 vs. 16.8 ± 6.8, P = 0.002), and CD4/CD8 ratio (7.9 ± 2.8 vs. 3.9 ± 1.5, P < 0.001) in BALF between the symptomatic group and asymptomatic group (all P < 0.05). The T cells (rs = 0.447, P = 0.011), CD4 (rs = 0.572, P = 0.002), and CD4/CD8 ratio (rs = 0.701, P < 0.001) in BALF were positively correlated with respiratory symptoms.

CONCLUSION

The LP in LNPF, BALF and PB were significantly different and the main index correlated with respiratory symptoms was CD4/CD8 ratio in BALF. The difference of LP in BALF and LNPF may help to deeply understand the pathophysiological process and may reflect the different degree of lung and lymph node lesion.

Nasopharyngeal aspirates in children with severe community-acquired pneumonia collected within 3 days before bronchoscopy can partially reflect the pathogens in bronchoalveolar lavage fluids

BACKGROUND

There is little evidence about consistency between nasopharyngeal and pulmonary pathogens in children with severe pneumonia. This study aims to compare the difference of pathogens between nasopharyngeal aspirates (NPAs) collected before bronchoscopy and bronchoalveolar lavage fluids (BALFs) in children with severe community-acquired pneumonia (SCAP).

METHODS

NPAs and BALFs were collected form pediatric SCAP cases hospitalized from January 2018 to March 2019. NPAs were colleced within 3 days before bronchoscopy. Samples were detected by direct immunofluorescence assay (DFA) for seven respiratory viruses and by routine bacterial culture in the clinical microbiology laboratory. Respiratory syncytial virus (RSV), Adenovirus (ADV), Influenza virus types A, B (IV-A and IV-B), Parainfluenza virus 1-3 (PIV1-3) were detected with a commercial assay. The virological and bacteriological detention results of NPAs were compared with the results of BALFs.

RESULTS

In total 204 cases with mean age of 3.4 ± 2.8 years (IQR, 1 month-14 years) were included in the study. Both NPA and BALF were collected from those cases. The positive rates of pathogen in NPAs and BALFs were 25.0% (51/204) and 36.7% (75/204), respectively (x² = 6.614, P = 0.010). Respiratory viruses were found in 16.1% (33/204) from NPAs and 32.3% (66/204) from BALFs (x² = 14.524, P < 0.001). RSV and ADV were the two most frequent detected viruses in NPAs and BALFs. High consistentcy of pathogens between NPAs and BALFs was observed, and 96.9% (32/33) viruses detected in NPAs were also found in BALFs. While bacteria were isolated from 12.7% (26/204) and 10.7% (22/204) of the two kinds of samples, respectively (x² = 0.378, P = 0.539). In addition, Haemophilus influenzae (HI) was the dominant germ in both samples.

CONCLUSION

The DFA method used to detect seven respiratory viruses from NPAs collected within 3 days before bronchoscopy can partially reflect the pathogens in the lungs in children with SCAP.

Edible algae (Ecklonia cava) bioprocessed with mycelia of shiitake (Lentinula edodes) mushrooms in liquid culture and its isolated fractions protect mice against allergic asthma

BACKGROUND

Ecklonia cava is an edible marine brown alga harvested from the ocean that is widely consumed in Asian countries as a health-promoting medicinal food The objective of the present study is to evaluate the anti-asthma mechanism of a new functional food produced by bioprocessing edible algae Ecklonia cava and shiitake Lentinula edodes mushroom mycelia and isolated fractions.

METHODS

We used as series of methods, including high performance liquid chromatography, gas chromatography, cell assays, and an in vivo mouse assay to evaluate the asthma-inhibitory effect of Ecklonia cava bioprocessed (fermented) with Lentinula edodes shiitake mushroom mycelium and its isolated fractions in mast cells and in orally fed mice.

RESULTS

The treatments inhibited the degranulation of RBL-2H3 cells and immunoglobulin E (IgE) production, suggesting anti-asthma effects in vitro. The in vitro anti-asthma effects in cells were confirmed in mice following the induction of asthma by alumina and chicken egg ovalbumin (OVA). Oral administration of the bioprocessed Ecklonia cava and purified fractions suppressed the induction of asthma and was accompanied by the inhibition of inflammation- and immune-related substances, including eotaxin; thymic stromal lymphopoietin (TSLP); OVA-specific IgE; leukotriene C4 (LTC4); prostaglandin D2 (PGD2); and vascular cell adhesion molecule-1 (VCAM-1) in bronchoalveolar lavage fluid (BALF) and other fluids and organs. Th2 cytokines were reduced and Th1 cytokines were restored in serum, suggesting the asthma-induced inhibitory effect is regulated by the balance of the Th1/Th2 immune response. Serum levels of IL-10, a regulatory T cell (Treg) cytokine, were increased, further favoring reduced inflammation. Histology of lung tissues revealed that the treatment also reversed the thickening of the airway wall and the contraction and infiltration of bronchial and blood vessels and perialveolar inflammatory cells. The bioprocessed Ecklonia cava/mushroom mycelia new functional food showed the highest inhibition as compared with commercial algae and the fractions isolated from the bioprocessed product.

CONCLUSIONS

The in vitro cell and in vivo mouse assays demonstrate the potential value of the new bioprocessed formulation as an anti-inflammatory and anti-allergic combination of natural compounds against allergic asthma and might also ameliorate allergic manifestations of foods, drugs, and viral infections.

First evidence of microplastics isolated in European citizens' lower airway

Microplastics (MPs) have been detected in all environmental locations, including the atmosphere. However, few studies have investigated the presence of airborne MPs in the human respiratory system. Our research purpose was to investigate these pollutants in the lower human airways of 44 adult European citizens, using bronchoalveolar lavage fluid (BALF) collection as a minimally invasive method, that enables the detection of these pollutants in living patients. We studied the relationship between the patients' life habits and physiological parameters, based on background information and medical and occupational history, and the concentration of MPs isolated from their respiratory systems. Our results indicate that most MPs were in the form of microfibers (MFs) (97.06%), with an average concentration of 9.18 ± 2.45 items/100 mL BALF, and only 5.88% (0.57 ± 0.27 items/100 mL BALF) were particulate MPs, without a significant relationship with environmental, physiological, or clinical factors. The average size was 1.73 ± 0.15 mm, with the longest dimension (9.96 mm) corresponding to a polyacrylic fiber. Taken together, the results demonstrated the occurrence of MPs in the lower human airway, although more studies are necessary to elucidate the negative effects these pollutants could induce in the human respiratory system and its associated diseases.

MiR-223-3p-loaded exosomes from bronchoalveolar lavage fluid promote alveolar macrophage autophagy and reduce acute lung injury by inhibiting the expression of STK39

This study investigated the molecular mechanism by which bronchoalveolar lavage fluid exosomes (BALF-exo) alleviated acute lung injury (ALI). BALF-exo was isolated from mice. LPS was used to induce inflammation in rat alveolar macrophages (NR8383). NR8383 cell models were treated with BALF-exo or BALF-exo loaded with miR-223-3p mimics/inhibitors, or STK39 was overexpressed in NR8383 cells before LPS and BALF-exo treatment. These cells were subjected to apoptosis, autophagy, and inflammation assays. RNA immunoprecipitation and dual-luciferase reporter assay were conducted to verify the binding between miR-223-3p and STK39. LPS-induced ALI mouse models were treated with BALF-exo loaded with miR-223-3p mimics. miR-223-3p was lowly expressed in BALF-exo from LPS-treated mice. BALF-exo loaded with miR-223-3p mimics increased viability and autophagy and decreased apoptosis and inflammation in NR8383 cell models. Inhibition of miR-223-3p in BALF-exo or overexpression of STK39 in NR8383 cells repressed the therapeutic effect of BALF-exo in LPS-treated NR8383 cells. STK39 was a target gene of miR-223-3p. miR-223-3p shuttled by BALF-exo negatively regulated the expression of STK39 in NR8383 cells. BALF-exo loaded with miR-223-3p mimics also reduced lung injuries in ALI mice. In conclusion, miR-223-3p loaded in BALF-exo alleviates ALI by targeting STK39 in alveolar macrophages.

Diagnostic performance of metagenomic next-generation sequencing for the detection of pathogens in bronchoalveolar lavage fluid in patients with pulmonary infections: Systematic review and meta-analysis

BACKGROUND

The identification of pathogens in patients with pulmonary infection has always been a major challenge in medicine. Compared with sputum and throat swabs, bronchoalveolar lavage fluid (BALF) can better reflect the actual state in the lungs. However, there has not been a meta-analysis of the diagnostic efficacy of metagenomic next-generation sequencing (mNGS) in detecting pathogens in BALF from patients with pulmonary infections.

METHODS

Data sources were PubMed, Web of Science, Embase, and the China National Knowledge Infrastructure. The pooled sensitivity and specificity were estimated by using random-effects or fixed-effect models. Subgroup analysis was performed to reveal the effect of potential explanatory factors on the diagnostic performance measures.

RESULTS

The pooled sensitivity was 78% (95% confidence interval: 67-87%; I² = 92%) and the pooled specificity was 77% (95% confidence interval: 64-94%; I² = 74%) for mNGS. Subgroup analyses for the sensitivity of mNGS revealed that patients with pulmonary infections who were severely ill or immunocompromised significantly affected heterogeneity (P < 0.001). The positive detection rate of mNGS for pathogens in BALF of severely or immunocompromised pulmonary-infected patients was 92% (95% confidence interval: 78-100%).

CONCLUSION

mNGS has high diagnostic performance for BALF pathogens in patients with pulmonary infections, especially in critically ill or immunocompromised patients.

Diagnostic value of metagenomic next-generation sequencing of bronchoalveolar lavage fluid for the diagnosis of suspected pneumonia in immunocompromised patients

Background

To evaluate the diagnostic value of metagenomic next-generation sequencing (mNGS) of bronchoalveolar lavage fluid (BALF) in immunocompromised patients for the diagnosis of suspected pneumonia in comparison with that of conventional microbiological tests (CMTs).

Methods

Sixty-nine immunocompromised patients with suspected pneumonia received both CMTs and mNGS of BALF were analyzed retrospectively. The diagnostic value was compared between CMTs and mNGS, using the clinical composite diagnosis as the reference standard.

Results

Sixty patients were diagnosed of pneumonia including fifty-two patients with identified pathogens and eight patients with probable pathogens. Taking the composite reference standard as a gold standard, 42 pathogens were identified by CMTs including nine bacteria, 17 fungi, 8 virus, 6 Mycobacterium Tuberculosis, and two Legionella and 19(45%) of which were detected by BALF culture. As for mNGS, it identified 76 pathogens including 20 bacteria, 31 fungi, 14 virus, 5 Mycobacterium Tuberculosis, four Legionella and two Chlamydia psittaci. The overall detection rate of mNGS for pathogens were higher than that of CMTs. However, a comparable diagnostic accuracy of mNGS and CMTs were found for bacterial and viral infections. mNGS exhibited a higher diagnostic accuracy for fungal detection than CMTs (78% vs. 57%, P < 0.05), which mainly because of the high sensitivity of mNGS in patients with Pneumocystis jirovecii pneumonia (PJP) (100% vs. 28%, P < 0.05). Nineteen patients were identified as pulmonary co-infection, mNGS test showed a higher detection rate and broader spectrum for pathogen detection than that of CMTs in co-infection. Moreover, Pneumocystis jirovecii was the most common pathogen in co-infection and mNGS have identified much more co-pathogens of PJP than CMTs.

Conclusions

mNGS of BALF improved the microbial detection rate of pathogens and exhibited remarkable advantages in detecting PJP and identifying co-infection in immunocompromised patients.

Supplementary Information

The online version contains supplementary material available at 10.1186/s12879-022-07381-8.

Evaluation of the diagnostic accuracy of galactomannan from the bronchoalveolar lavage fluid of patients with suspected invasive pulmonary aspergillosis

BACKGROUND

Several studies to evaluate the accuracy of galactomannan (GM) in bronchoalveolar lavage fluid (BALF) as a diagnostic tool have been carried out; however, there are still controversies about the optimal cut-off point of BALF GM.

AIMS

The objective of this study was to determine the diagnostic accuracy and the optimal cut-off point on BALF GM from patients with suspected invasive pulmonary aspergillosis (IPA) in a tertiary care hospital.

METHODS

A cross-sectional study with 188 patients (≥18 years) that had undergone a bronchoscopy with BAL due to suspected IPA was carried out. IPA was diagnosed according to the EORTC/MSG guidelines.

RESULTS

The optimal optical density cut-off point for BALF GM was 0.67, with sensitivity, specificity, positive predictive value, and negative predictive value of 100%, 70%, 32.3%, and 100%, respectively.

CONCLUSIONS

BALF GM detection proved to be a useful supplementary technique in the early diagnosis of IPA in both neutropenic and non-neutropenic patients.

RNA sequencing reveals the emerging role of bronchoalveolar lavage fluid exosome lncRNAs in acute lung injury

Background

Bronchoalveolar lavage fluid (BALF) exosomes possess different properties in different diseases, which are mediated through microRNAs (miRNAs) and long noncoding RNAs (lncRNAs), among others. By sequencing the differentially expressed lncRNAs in BALF exosomes, we seek potential targets for the diagnosis and treatment of acute lung injury (ALI).

Methods

Considering that human and rat genes are about 80% similar, ALI was induced using lipopolysaccharide in six male Wistar rats, with six rats as control (all weighing 200 ± 20 g and aged 6-8 weeks). BALF exosomes were obtained 24 h after ALI. The exosomes in BALF were extracted by ultracentrifugation. The differential expression of BALF exosomal lncRNAs in BALF was analyzed by RNA sequencing. Gene Ontology (GO) and Kyoto Encyclopedia of Genes and Genomes (KEGG) analyses were performed to predict the functions of differentially expressed lncRNAs, which were confirmed by reverse transcription-polymerase chain reaction.

Results

Compared with the control group, the ALI group displayed a higher wet/dry ratio, tumor necrosis factor-α levels, and interleukin-6 levels (all P < 0.001). The airway injection of exosomes in rats led to significant infiltration by neutrophils. A total of 2,958 differentially expressed exosomal lncRNAs were identified, including 2,524 upregulated and 434 downregulated ones. Five lncRNAs confirmed the reliability of the sequencing data. The top three GO functions were phagocytic vesicle membrane, regulation of receptor biosynthesis process, and I-SMAD binding. Salmonella infection, Toll-like receptor signaling pathway, and osteoclast differentiation were the most enriched KEGG pathways. The lncRNA-miRNA interaction network of the five confirmed lncRNAs could be predicted using miRDB.

Conclusions

BALF-derived exosomes play an important role in ALI development and help identify potential therapeutic targets related to ALI.

Quantitative proteomic analysis of bronchoalveolar lavage fluid in West Highland white terriers with canine idiopathic pulmonary fibrosis

Background

Canine idiopathic pulmonary fibrosis (CIPF) is a chronic, progressive, interstitial fibrosing lung disease, manifesting as cough, exercise intolerance and ultimately, dyspnea and respiratory failure. It mainly affects West Highland white terriers (WHWTs), lacks curable treatment and has a poor prognosis. Aspiration of gastroesophageal refluxate may play a role in the development of CIPF. In the first part of this study, we completed label-free quantitative proteomic analysis of bronchoalveolar lavage fluid (BALF) from CIPF and healthy WHWTs. In the second part, we evaluated potential protein markers of reflux aspiration from canine gastric juice and vomitus and whether these were present in BALF from the two groups.

Results

Across all BALF samples, 417 proteins were identified, and of these, 265 proteins were identified by two or more unique tryptic peptides. Using the 265 high confidence assignments, the quantitative proteome profiles were very similar in the two cohorts, but they could be readily resolved by principal component analysis on the basis of differential protein expression. Of the proteins that were differentially abundant in the two groups, several (including inflammatory and fibrotic markers) were elevated in CIPF, and a smaller, more diverse group of proteins were diminished in CIPF. No protein markers indicative of reflux aspiration were identified.

Conclusions

Label-free proteomics allowed discrimination between CIPF and healthy WHWTs, consistent with fibrotic process but did not provide clear evidence for gastrointestinal aspiration. The measurement of proteins may provide a proteomics signature of CIPF that could be used to evaluate treatment options.

Supplementary Information

The online version contains supplementary material available at 10.1186/s12917-022-03202-x.

Cytopathological analysis of bronchoalveolar lavage fluid in patients with and without HIV infection

BACKGROUND

Human immunodeficiency virus/acquired immunodeficiency syndrome (HIV/AIDS) infection can lead to a broad spectrum of lung diseases, including infectious diseases and tumors. Recently, with the wide application of bronchoscopes and cytopathology of bronchoalveolar lavage fluid (BALF), the diagnostic efficiency of lung diseases has improved. The present study focuses on analyzing the cytopathologic characteristics of BALF in the diagnosis of HIV/AIDS-related lung disease and comparing the lung disease spectrum between HIV and HIV-uninfected patients.

METHODS

BALF specimens were collected from 2211 patients. Using ThinPrep liquid-based technology, the cytologic smears were prepared by staining with Hematoxylin and Eosin (HE), Gomori's methenamine silver (GMS), and Periodic Acid Schiff (PAS), acid-fast and immunocytochemical (ICC) staining. Real-time PCR was used to detect cytomegalovirus (CMV) and Mycobacterium tuberculosis (M. tuberculosis) in the remaining BALF. PCR-reverse dot hybridization was used for mycobacterial species identification.

RESULTS

From the 2211 BALF specimens, 1768 (79.96%) were specimens from HIV-infected patients, and 443 (20.04%) were speciments from HIV-uninfected patients. The HIV-infected patients with a median age of 38.5 ± 11.3 years were markedly younger than the HIV-uninfected patients (52.9 ± 14.9 years) (p < 0.01). We found that 1635 (92.5%) HIV-infected patients were males, showing a prominently higher proportion than those without HIV infection (71.1%) (p < 0.01). Meanwhile, 1045 specific lesions were found in 1768 HIV-infected patients (59.1%), including 1034 cases of infectious diseases and 11 neoplastic lesions, also exhibiting a distinctly higher proportion compared to the HIV-uninfected patients (12.2%) (p < 0.001). For the HIV-infected group, a distinctly higher proportion of single infection lesions (724/1768, 41%) was noted than the HIV-uninfected group (14/443, 3.2%) (p < 0.001). Among single infection lesions, the most common was Cytomegalovirus(CMV) infection (20.9%) for the HIV-infected group, followed by Pneumocystis jiroveci(PJ) (13.0%), Fungal (3.5%), and Mycobacterial infections (3.4%), of which M. tuberculosis infection accounted for 3.1%. Double infections (300/1768, 17.0%) and Triple infections (10/1768, 0.6%) were found only among the patients with HIV. The malignancies among HIV-infected patients included adenocarcinomas (0.22%), small cell carcinomas (0.2%), squamous cell carcinomas (0.1%), and diffuse large B-cell lymphoma (0.1%). HIV-infected patients exhibited a significantly lower incidence of neoplastic lesions (0.6% vs. 9.0%) than the HIV-uninfected patients (p < 0.001).

CONCLUSIONS

There was a significant difference in the spectrum of lung diseases between HIV-infected and non-infected patients diagnosed by BALF cytopathology.

Effect of intrabronchial administration of autologous adipose-derived mesenchymal stem cells on severe equine asthma

BACKGROUND

Severe equine asthma (SEA) is a common chronic respiratory disease and a significant health and well-being problem in horses. Current therapeutic strategies improve pulmonary function and clinical signs in some horses, but in the long-term, return to full athletic function appears to be rare. The aim of this study was to assess the safety and the effect of intrabronchial administration of adipose-derived mesenchymal stem cells (AD-MSC) on pulmonary inflammatory and clinical parameters in horses with SEA.

METHODS

This was a randomized controlled trial. Twenty adult horses diagnosed with SEA were randomly divided into two groups (n = 10), and treated either with a single intrabronchial application of autologous AD-MSC or oral dexamethasone for three weeks. A targeted clinical examination with determination of clinical score, maximal change in pleural pressure during the breathing cycle, and an endoscopic examination of the airways were performed at baseline and three weeks after treatment. Bronchoalveolar lavage fluid was analyzed cytologically, and IL-1β, IL-4, IL-8, IL-17, TNFα and IFNγ mRNA and protein concentrations were measured at baseline and three weeks. The horses were then monitored over one year for recurrence of SEA. A non-inferiority analysis and a linear mixed-effects model were performed to assess differences between treatments.

RESULTS

The non-inferiority of AD-MSC treatment was not established. However, AD-MSC administration significantly ameliorated the clinical score (P = 0.01), decreased the expression of IL-17 mRNA (P = 0.05) and IL-1β (P ≤ 0.001), IL-4 (P ≤ 0.001), TNFα (P = 0.02) protein levels, and had a positive long-term effect on SEA-associated clinical signs (P = 0.02).

CONCLUSIONS

Intrabronchial administration of AD-MSC had limited short-term anti-inflammatory effects but improved the clinical signs of SEA at one year.

The role of pentraxin3 in plasma and bronchoalveolar lavage fluid in COPD patients with invasive pulmonary aspergillosis

Background

The use of galactomannan (GM) testing in plasma and bronchoalveolar lavage fluid (BALF) has improved the diagnosis of invasive pulmonary aspergillosis (IPA) in patients with chronic obstructive pulmonary disease (COPD); however, the high false-positive rate leads to overdiagnosis. Pentraxin 3 (PTX3) as an indicator of inflammation plays an important role in resistance to Aspergillus infections. This study aimed to investigate the diagnostic value of PTX3 for diagnosing IPA with COPD.

Methods

We retrospectively collected data on patients with suspected COPD and IPA who had been hospitalized in the Third Affiliated Hospital of Soochow University between September 2017 and November 2020. PTX3 and GM were measured using enzyme-linked immunosorbent assays.

Results

A total of 165 patients were included in the study, of whom 35 had confirmed or probable IPA. The remaining 130 patients served as controls. The median plasma and BALF PTX3 levels were significantly higher in patients with IPA than in control patients (3.74 ng/mL vs. 1.29 ng/mL, P < 0.001; and 3.88 ng/mL vs. 1.58 ng/mL, P < 0.001 in plasma and BALF, respectively). The plasma GM, plasma PTX3, BALF GM, and BALF PTX3 assays had sensitivities of 60.0%, 77.1%, 78.6%, and 89.3%, respectively, and specificities of 73.8%, 69.2%, 80.7%, and 77.1%, respectively. The sensitivity of PTX3 in plasma and BALF was higher than that of GM. However, the specificity of PTX3 and GM did not differ significantly between the IPA group and the control group. The specificity of the assays for the diagnosis of IPA was > 90% in patients who were PTX3-positive and GM-positive in plasma and BALF.

Conclusions

BALF and plasma PTX3 levels were significantly higher in COPD patients with IPA. The sensitivity of PTX3 was superior to that of GM for diagnosing IPA in patients with COPD. The combination of GM and PTX3 is useful for the diagnosis of IPA in patients with COPD.

Tryptase and IL-33 in Bronchoalveolar Lavage Fluid May Predict the Types of Eosinophilic Pneumonia and Disease Recurrence

INTRODUCTION

Eosinophilic pneumonia (EP) is characterized by a marked accumulation of eosinophils in the lungs and blood. Eosinophils and mast cells play an important role in the pathogenesis of EP via release of biomarkers such as tryptase and interleukin (IL)-33. However, the potential role of these biomarkers is not fully understood.

OBJECTIVES

We aimed to evaluate the differences among the levels of tryptase and IL-33 in bronchoalveolar lavage fluid (BALF) from several types of EP. We evaluated the differences between the levels of these biomarkers in the recurrent and nonrecurrent cases.

METHOD

We prospectively collected the clinical data of patients with EP, diagnosed between 2006 and 2015 in our institution. Bronchoscopy was performed before steroid treatment; BALF was collected. The clinical characteristics of EP patients and the levels of tryptase and IL-33 in BALF were evaluated.

RESULTS

We enrolled 15 patients with chronic EP (CEP), 5 with acute EP (AEP), 10 with drug-induced EP, and 6 with angiitis-related EP. Tryptase levels in the CEP group were significantly higher than that in the drug-induced EP group (p = 0.048), while the AEP group had the highest IL-33 levels. Recurrence of EP was noted in 67% of patients with CEP. The levels of tryptase and IL-33 were notably higher in the recurrent cases than that in the nonrecurrent CEP group (p = 0.004, p = 0.04, respectively). Furthermore, there was a positive correlation between the levels of tryptase and IL-33 in the BALF of patients with CEP (ρ = 0.69, p = 0.004).

CONCLUSIONS

Tryptase and IL-33 in BALF are useful biomarkers for the assessment of EP types. These biomarkers could be used to predict disease recurrence.

[Analysis of the detection of metals and metalloids in the bronchoalveolar lavage fluid for the etiological diagnosis value of pneumoconiosis]

Objective: To analyze the differences of the concentrations of metals and metalloids in bronchoalveolar lavage fluid (BALF) of patients with pneumoconiosis, so as to provide reference for the etiological diagnosis of pneumoconiosis. Methods: From September 2019 to August 2020, 47 pneumoconiosis patients hospitalized in Chongqing Prevention and Treatment Center for Occupational Diseases and undergoing bronchoalveolar lavage were selected as the research objects using cluster sampling method. The general situation and occupational history of patients were investigated by questionnaire, The BALF of 47 pneumoconiosis patients was collected, and the concentrations of metals and metalloids in BALF were detected by inductively coupled plasma mass spectrometry (ICP-MS) , the differences among patients with different types of pneumoconiosis, different stages of silicosis and different occupational history were analyzed by one-way ANOVA. Results: The concentrations of 50 metals and metalloids in BALF were detected, and 21 of them were analyzed. Compared with different types of pneumoconiosis, the concentrations of Zn, Mn and Sn in BALF were statistically significant (F=9.959, 3.635, 9.488, P<0.05) . The concentrations of K, Mg, Fe, Zn, Cu and Ni in BALF were significantly different in different stages of silicosis (F=4.271, 4.334, 3.588, 5.120, 7.340, 3.905, P<0.05) . The concentrations of Zn and Sn in pneumoconiosis patients with different types of work and types of exposed dust were significantly different (P<0.05) . Conclusion: The detection of Zn, Mn, Sn, and other metals in BALF can provide reference basis for the etiological diagnosis of pneumoconiosis and provide a new idea for the diagnostic method of pneumoconiosis.

Consistency between nasopharyngeal aspirates and bronchoalveolar lavage fluid in pathogen detection in children with pneumonia: an analysis of 533 cases

OBJECTIVES

To study the consistency between nasopharyngeal aspirates (NPA) and bronchoalveolar lavage fluid (BALF) in pathogen detection in children with pneumonia.

METHODS

A retrospective analysis was performed on the data of pathogens detected in 533 children with pneumonia from February 2017 to March 2020. The paired McNemar's test was used to compare the difference in pathogen detection between NPA and BALF groups. The Kappa coefficient was used to analyze the consistency in pathogen detection between the two groups.

RESULTS

NPA had a sensitivity of 28%, a specificity of 74%, a positive predictive value of 14%, and a negative predictive value of 91% in detecting bacteria, and a Kappa coefficient of 0.013 suggested poor consistency between NPA and BALF. NPA had a sensitivity of 52%, a specificity of 81%, a positive predictive value of 24%, and a negative predictive value of 94% in detecting viruses, and a Kappa coefficient of 0.213 suggested poor consistency between NPA and BALF. NPA had a sensitivity of 78%, a specificity of 71%, a positive predictive value of 49%, and a negative predictive value of 90% in detecting Mycoplasma pneumoniae, and a Kappa coefficient of 0.407 suggested moderate consistency between NPA and BALF.

CONCLUSIONS

There is poor consistency between NPA and BALF in the detection of bacteria and viruses, and clinicians should be cautious in diagnosing lower respiratory tract infection based on bacteria or viruses detected in NPA. There is moderate consistency between NPA and BALF in the detection of Mycoplasma pneumoniae, suggesting that it may be reliable to diagnose lower respiratory tract infection based on Mycoplasma pneumoniae detected in NPA, while comprehensive judgment in combination with clinical conditions is needed.

Automated interpretation and analysis of bronchoalveolar lavage fluid

BACKGROUND

The cytological analysis of bronchoalveolar lavage fluid (BALF) plays an essential role in the differential diagnosis of respiratory diseases. In recent years, deep learning has demonstrated excellent performance in image processing and object recognition.

OBJECTIVES

We aim to apply deep learning to the automated interpretation and analysis of BALF.

METHOD

Visual images were acquired using an automated biological microscopy platform. We propose a three-step algorithm to automatically interpret BALF cytology based on a convolutional neural network (CNN). The clinical value was evaluated at the patient level.

RESULTS

Our model successfully detected most cells in BALF specimens and achieved a sensitivity, precision, and F1 score of over 0.9 for most cell types. In two tests in the clinical context, the algorithm outperformed experienced practitioners.

CONCLUSION

The program can automatically provide the cytological background of BALF and augment clinical decision-making for clinicians.

The cellular composition of the lung lining fluid gradually changes from bronchus to alveolus

Although large advances have recently been made mapping out the cellular composition of lung tissue using single cell sequencing, the composition and distribution of the cellular elements within the lining fluid of the lung has not been extensively studied. Here, we assessed the cellular composition of the lung lining fluid by performing a differential cell analysis on bronchoalveolar lavage fluid (BALF) and epithelial lining fluid (ELF) at four different locations within the lung in post-lung transplantation patients. The percentage of neutrophils and lymphocytes is reduced in more distal regions of the lungs, while the percentage of macrophages increases in these more distal regions. These data provide valuable information to determine which lung lining fluid sampling technique and location is best to use for measuring specific factors and biomarkers, and to increase the understanding of different cell populations in specific lung regions.

Diagnosis of pulmonary nodules by DNA methylation analysis in bronchoalveolar lavage fluids

BACKGROUND

Lung cancer is the leading cause of cancer-related mortality. The alteration of DNA methylation plays a major role in the development of lung cancer. Methylation biomarkers become a possible method for lung cancer diagnosis.

RESULTS

We identified eleven lung cancer-specific methylation markers (CDO1, GSHR, HOXA11, HOXB4-1, HOXB4-2, HOXB4-3, HOXB4-4, LHX9, MIR196A1, PTGER4-1, and PTGER4-2), which could differentiate benign and malignant pulmonary nodules. The methylation levels of these markers are significantly higher in malignant tissues. In bronchoalveolar lavage fluid (BALF) samples, the methylation signals maintain the same differential trend as in tissues. An optimal 5-marker model for pulmonary nodule diagnosis (malignant vs. benign) was developed from all possible combinations of the eleven markers. In the test set (57 tissue and 71 BALF samples), the area under curve (AUC) value achieves 0.93, and the overall sensitivity is 82% at the specificity of 91%. In an independent validation set (111 BALF samples), the AUC is 0.82 with a specificity of 82% and a sensitivity of 70%.

CONCLUSIONS

This model can differentiate pulmonary adenocarcinoma and squamous carcinoma from benign diseases, especially for infection, inflammation, and tuberculosis. The model's performance is not affected by gender, age, smoking history, or the solid components of nodules.