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Virulence Dec 2024(APP) is an important pathogen of the porcine respiratory disease complex, which leads to huge economic losses worldwide. We previously demonstrated that -producing...
(APP) is an important pathogen of the porcine respiratory disease complex, which leads to huge economic losses worldwide. We previously demonstrated that -producing bovine neutrophil β-defensin-5 (B5) could resist the infection by the bovine intracellular pathogen . In this study, the roles of synthetic B5 in regulating mucosal innate immune response and protecting against extracellular APP infection were further investigated using a mouse model. Results showed that B5 promoted the production of tumour necrosis factor (TNF)-α, interleukin (IL)-1β, and interferon (IFN)-β in macrophages as well as dendritic cells (DC) and enhanced DC maturation . Importantly, intranasal B5 was safe and conferred effective protection against APP via reducing the bacterial load in lungs and alleviating pulmonary inflammatory damage. Furthermore, in the early stage of APP infection, we found that intranasal B5 up-regulated the secretion of TNF-α, IL-1β, IL-17, and IL-22; enhanced the rapid recruitment of macrophages, neutrophils, and DC; and facilitated the generation of group 3 innate lymphoid cells in lungs. In addition, B5 activated signalling pathways associated with cellular response to IFN-β and activation of innate immune response in APP-challenged lungs. Collectively, B5 via the intranasal route can effectively ameliorate the immune suppression caused by early APP infection and provide protection against APP. The immunization strategy may be applied to animals or human respiratory bacterial infectious diseases. Our findings highlight the potential importance of B5, enhancing mucosal defence against intracellular bacteria like APP which causes early-phase immune suppression.
Topics: Humans; Swine; Animals; Cattle; Immunity, Innate; Actinobacillus pleuropneumoniae; Lymphocytes; Lung; Tumor Necrosis Factor-alpha; Immunosuppression Therapy
PubMed: 38378464
DOI: 10.1080/21505594.2024.2316459 -
Veterinary Research Apr 2023Actinobacillus equuli is mostly associated with disease in horses and is most widely known as the causative agent of sleepy foal disease. Even though existing phenotypic...
Actinobacillus equuli is mostly associated with disease in horses and is most widely known as the causative agent of sleepy foal disease. Even though existing phenotypic tools such as biochemical tests, 16S rRNA gene sequencing, and Matrix Assisted Laser Desorption Ionization Time of Flight Mass Spectrometry (MALDI-TOF MS) can be used to identify members of the Actinobacillus genus, these methods struggle to differentiate between certain species and do not allow strain, virulence, and antimicrobial susceptibility typing. Hence, we performed in-depth analysis of 24 equine Actinobacillus isolates using phenotypic identification and susceptibility testing on the one hand, and long-read nanopore whole genome sequencing on the other hand. This allowed to address strain divergence down to the whole genome single nucleotide polymorphism (SNP) level. While lowest resolution was observed for 16S rRNA gene classification, a new multi-locus sequence typing (MLST) scheme allowed proper classification up to the species level. Nevertheless, a SNP-level analysis was required to distinguish A. equuli subspecies equuli and haemolyticus. Our data provided first WGS data on Actinobacillus genomospecies 1, Actinobacillus genomospecies 2, and A. arthritidis, which allowed the identification of a new Actinobacillus genomospecies 1 field isolate. Also, in-depth characterization of RTX virulence genes provided information on the distribution, completeness, and potential complementary nature of the RTX gene operons within the Actinobacillus genus. Even though overall low prevalence of acquired resistance was observed, two plasmids were identified conferring resistance to penicillin-ampicillin-amoxicillin and chloramphenicol in one A. equuli strain. In conclusion our data delivered new insights in the use of long-read WGS in high resolution identification, virulence gene typing, and antimicrobial resistance (AMR) of equine Actinobacillus species.
Topics: Animals; Horses; Actinobacillus; Anti-Bacterial Agents; Multilocus Sequence Typing; RNA, Ribosomal, 16S; Virulence; Drug Resistance, Bacterial; Whole Genome Sequencing
PubMed: 37020296
DOI: 10.1186/s13567-023-01160-2 -
Annals of Hepatology 2023Recent translational research indicated a bidirectional relationship between NASH (non-alcoholic steatohepatitis) and periodontitis; however, few clinical cohorts have...
INTRODUCTION AND OBJECTIVES
Recent translational research indicated a bidirectional relationship between NASH (non-alcoholic steatohepatitis) and periodontitis; however, few clinical cohorts have studied this in detail. Thus we investigated this assumed association in a well-defined cohort.
MATERIALS AND METHODS
Data were generated prospectively for 132 patients (32 patients with NASH and 100 unselected, consecutively collected, anonymized controls from a local dental practice): detailed periodontal parameters, i.e., pocket-probing-depths (PPD), bleeding-on-probing (BOP), plaque-index, and utilization of dental care were assessed and correlated with relevant hepatic parameters (liver stiffness via fibroscan, AST, ALT, bilirubin, and MELD-score). Gingiva samples were tested for Porphyromonas gingvalis (P.g.) and Actinobacillus actinomyctemcomitans (A.a.) by PCR.
RESULTS
87.5% of NASH patients and 47% of controls suffered from moderate to severe periodontitis (p=0.01). Liver stiffness was significantly correlated with elevated PPD (p=0.02) and BOP (p=0.03). 34 % of the NASH patients did not make use of regular dental health care. In these patients, AST (p=0.04), MELD score (p<0.01), and liver stiffness (p=0.01) were significantly elevated compared to those who see a dentist regularly. The severity of NASH was not associated with the intraoral detection of P.g. and A.a.
CONCLUSIONS
The present study suggests that NASH might be associated with periodontitis, irrespective of the intraoral presence of P.g. and A.a. Moreover, regular dental care utilization might mitigate the course of NASH, and patients should be reminded by their hepatologists of the importance of regular dental visits. Future studies should investigate the role of regular dental care and additional anti-inflammatory treatments of the oral cavity.
Topics: Humans; Prevalence; Porphyromonas gingivalis; Periodontal Diseases; Periodontitis; Non-alcoholic Fatty Liver Disease
PubMed: 36646168
DOI: 10.1016/j.aohep.2022.100887 -
Frontiers in Microbiology 2023() is a member of in family Pasteurellaceae. It is the causative agent of porcine pleuropneumonia, which has caused huge economic losses to pig industry over the...
INTRODUCTION
() is a member of in family Pasteurellaceae. It is the causative agent of porcine pleuropneumonia, which has caused huge economic losses to pig industry over the world. Cysteine is a precursor of many important biomolecules and defense compounds in the cell. However, molecular mechanisms of cysteine transport in are unclear.
METHODS
In this study, gene-deleted mutants were generated and investigated, to reveal the roles of potential cysteine/cystine transport proteins FliY and YdjN of .
RESULTS
Our results indicated that the growth of was not affected after or single gene deletion, but absence of both FliY and YdjN decreased the growth ability significantly, when cultured in the chemically defined medium (CDM) supplemented with cysteine or cystine as the only sulfur source. double deletion mutant ΔΔ showed increased sensitivity to oxidative stress. Besides, -complementation of YdjN into ΔΔ and wild type leads to increased biofilm formation in CDM. However, the virulence of ΔΔ was not attenuated in mice or pigs.
DISCUSSION
These findings suggest that FliY and YdjN are involved in the cysteine/cystine acquisition, oxidative tolerance, and biofilm formation, but not contribute to the pathogenicity of .
PubMed: 37250053
DOI: 10.3389/fmicb.2023.1169774 -
Frontiers in Cellular and Infection... 2023Currently, limited attention has been directed toward utilizing clinical cohorts as a starting point to elucidate alterations in the lower respiratory tract (LRT)...
BACKGROUND
Currently, limited attention has been directed toward utilizing clinical cohorts as a starting point to elucidate alterations in the lower respiratory tract (LRT) microbiota following influenza A virus (IAV) infection.
OBJECTIVES
Our objective was to undertake a comparative analysis of the diversity and composition of sputum microbiota in individuals afflicted by severe and critically ill influenza patients.
METHODS
Sputum specimens were procured from patients diagnosed with IAV infection for the purpose of profiling the microbiota using 16S-rDNA sequencing. To ascertain taxonomic differences between the severe and critically ill influenza cohorts, we leveraged Linear Discriminant Analysis Effect Size (LEfSe). Additionally, Spearman correlation analysis was employed to illuminate associations between sputum microbiota and influenza Ct values alongside laboratory indicators.
RESULTS
Our study encompassed a total cohort of 64 patients, comprising 48 within the severe group and 16 within the critically ill group. Intriguingly, exhibited significant depletion in the critically ill cohort (=0.031). The sputum microbiomes of the severe influenza group were hallmarked by an overrepresentation of , and , yielding ROC-plot AUC values of 0.71, 0.68, 0.60, 0.70, 0.70, and 0.68, respectively. Notably, exhibited an inverse correlation with influenza Ct values. Moreover, C-reactive protein (CRP) manifested a positive correlation with and .
CONCLUSION
The outcomes of this investigation lay the groundwork for future studies delving into the connection between the LRT microbiome and respiratory disorders. Further exploration is warranted to elucidate the intricate mechanisms underlying the interaction between IAV and , particularly in disease progression.
Topics: Humans; Influenza, Human; Sputum; Critical Illness; Bacteroidetes; Influenza A virus; Microbiota
PubMed: 38188635
DOI: 10.3389/fcimb.2023.1297946 -
Veterinary World Sep 2020Due to the incomplete development of the immune system in immature piglets, the respiratory tract is susceptible to invasion by numerous pathogens that cause a range of...
BACKGROUND AND AIM
Due to the incomplete development of the immune system in immature piglets, the respiratory tract is susceptible to invasion by numerous pathogens that cause a range of potential respiratory diseases. However, few studies have reported the changes in pig lung microorganisms during respiratory infection. Therefore, we aimed to explore the differences in lung environmental microorganisms between healthy piglets and piglets with respiratory diseases.
MATERIALS AND METHODS
Histopathological changes in lung sections were observed in both diseased and healthy pigs. Changes in the composition and abundance of microbiomes in alveolar lavage fluid from eleven 4-week-old Chinese Kele piglets (three clinically healthy and eight diseased) were studied by IonS5™ XL sequencing of the bacterial16S rRNA genes.
RESULTS
Histopathological sections showed that diseased pigs displayed more lung lesions than healthy pigs. Diseased piglets harbored lower bacterial operational taxonomic units, α-diversity, and bacterial community complexity in comparison to healthy piglets. Taxonomic composition analysis showed that in the diseased piglets, the majority of flora was composed of , , and ; while , , and were dominant in the control group. The abundance of was significantly higher in ill piglets (p<0.05), and the phylogenetic tree indicated that was clustered in , a conditional pathogen that has the potential to affect the swine respiratory system.
CONCLUSION
The results of this study show that the microbial species and structure of piglets' lungs were changed during respiratory tract infection. The finding of suggested that besides known pathogens such as and , unknown pathogens can exist in the respiratory system of diseased pigs and provide a potential basis for clinical treatment.
PubMed: 33132613
DOI: 10.14202/vetworld.2020.1970-1981 -
International Journal of Molecular... Sep 2021is a pathogen that infects pigs and poses a serious threat to the pig industry. The emergence of quinolone-resistant strains of further limits the choice of treatment....
is a pathogen that infects pigs and poses a serious threat to the pig industry. The emergence of quinolone-resistant strains of further limits the choice of treatment. However, the mechanisms behind quinolone resistance in remain unclear. The genomes of a ciprofloxacin-resistant strain, SC1810 and its isogenic drug-sensitive counterpart were sequenced and analyzed using various bioinformatics tools, revealing 559 differentially expressed genes. The biological membrane, plasmid-mediated quinolone resistance genes and quinolone resistance-determining region were detected. Upregulated expression of efflux pump genes led to ciprofloxacin resistance. The expression of two porins, OmpP2B and LamB, was significantly downregulated in the mutant. Three nonsynonymous mutations in the mutant strain disrupted the water-metal ion bridge, subsequently reducing the affinity of the quinolone-enzyme complex for metal ions and leading to cross-resistance to multiple quinolones. The mechanism of quinolone resistance in may involve inhibition of expression of the outer membrane protein genes and to decrease drug influx, overexpression of AcrB in the efflux pump to enhance its drug-pumping ability, and mutation in the quinolone resistance-determining region to weaken the binding of the remaining drugs. These findings will provide new potential targets for treatment.
Topics: Actinobacillus pleuropneumoniae; Biofilms; Porins; Quinolones; Transcriptome
PubMed: 34576206
DOI: 10.3390/ijms221810036 -
Frontiers in Microbiology 2020() and () are primary swine pathogens that have been frequently co-isolated from pigs suffering from severe respiratory disease. The purpose of this study was to...
() and () are primary swine pathogens that have been frequently co-isolated from pigs suffering from severe respiratory disease. The purpose of this study was to investigate the biological impacts of the interactions between and . A single- and dual-species culture model was established via HA9801 (serotype 2) and CVCC265 (serotype 1). The single or mixed biofilms were imaged by confocal laser scanning microscopy. The biomass and viable cells in biofilms were quantified by crystal violet staining and determination of colony-forming units. The antibiotic susceptibility was determined by a microdilution broth method. The differences in gene transcription in pure- or mixed-species biofilms of and was evaluated by quantitative PCR. and formed two-species biofilms when co-cultured . When co-cultured with , biofilm formation by was significantly increased with the absence of NAD that is necessary for the growth of . Moreover, compared with monocultures, the antibiotic resistance of and was both enhanced in the co-culture model. When grown in dual-species biofilms, for , genes associated with virulence factors, including exotoxins and adhesins, were significantly upregulated. For , virulence factor-related genes , , , and were highly induced. These results suggest that the interspecies interactions between and may be cooperative under specific conditions and may play an important role in the disease progression and persistent infection.
PubMed: 32373078
DOI: 10.3389/fmicb.2020.00507 -
Frontiers in Veterinary Science 2021A large variety of clinical manifestation in individual pigs occurs after infection with pathogens involved in porcine respiratory disease complex (PRDC). Some pigs are...
A large variety of clinical manifestation in individual pigs occurs after infection with pathogens involved in porcine respiratory disease complex (PRDC). Some pigs are less prone to develop respiratory disease symptoms. The variation in clinical impact after infection and the recovery capacity of an individual animal are measures of its resilience. In this paper, we examined which ones of a range of animal-based factors (rectal temperature, body weight, skin lesion scores, behavior, natural antibody serum levels, serum levels of white blood cells, and type of T and granulocyte subsets) when measured prior to infection are related to disease severity. These animal-based factors and the interaction with housing regimen of the piglets (conventional or enriched) were modeled using linear regression to predict disease severity using a dataset acquired from a previous study using a well-established experimental coinfection model of porcine reproductive and respiratory syndrome virus (PRRSV) and . Both PRRSV and are often involved in PRDC. Histological lung lesion score of each animal was used as a measure for PRDC severity after infection. Prior to infection, higher serum levels of lymphocytes (CD3), naïve T helper (CD3CD4CD8), CD8 (as well as higher relative levels of CD8), and memory T helper (CD3CD4CD8) cells and higher levels of granulocytes (CD172) were related to reduced disease severity in both housing systems. Raised serum concentrations of natural IgM antibodies binding to keyhole limpet hemocyanin (KLH) were also related to reduced disease severity after infection. Increased levels of skin lesions at the central body part (after weaning and before infection) were related to increased disease severity in conventional housing systems only. High resisters showed a lower histological lung lesion score, which appeared unrelated to sex. Body temperature, behavior, and growth prior to infections were influenced by housing regimen but could not explain the variation in lung lesion scores after infection. Raised basal lymphocyte counts and lower skin lesion scores are related to reduced disease severity independent of or dependent on housing system, respectively. In conclusion, our study identifies intrinsic animal-based measures using linear regression analysis that predicts resilience to infections in pigs.
PubMed: 34869719
DOI: 10.3389/fvets.2021.742877 -
Frontiers in Cellular and Infection... 2022Dental caries severely hinders efficient access to adequate energy in wildlife. Different food supplies will develop characteristic plaque, and the microorganisms of...
Dental caries severely hinders efficient access to adequate energy in wildlife. Different food supplies will develop characteristic plaque, and the microorganisms of these plaque are closely related to dental health. Here, plaque samples from panda cubs with caries and caries-free were collected for 16S rRNA high-throughput sequencing. All sequences clustered into 337 operational taxonomic units (OTUs; 97% identity), representing 268 independent species belonging to 189 genera, 98 families, 51 orders, 24 classes, and 13 phyla. Two groups shared 218 OTUs, indicating the presence of a core plaque microbiome. α diversity analysis showed that the microbial diversity in plaques with caries exceeded that of caries-free. The dominant phyla of plaque microbiota included Proteobacteria, Bacteroidetes, Firmicutes, Fusobacteria, and Actinobacteria. The dominant genera included , , , , , , , , and . β diversity analysis showed that the plaque microbial community structure was different between two groups. Using LEfSe analysis, 19 differentially abundant taxa were identified as potential biomarkers. Finally, function predictions analysis showed All the energy related metabolic pathways on KEGG level 2 were enriched in caries-active group. Consistent with the mainstream caries-causing narrative, our results illuminate the lack of information regarding the oral microflora composition and function within giant panda cubs.
Topics: Animals; Bacteria; Dental Caries; Humans; Microbiota; RNA, Ribosomal, 16S; Ursidae
PubMed: 35573790
DOI: 10.3389/fcimb.2022.866410