Your browser doesn't support javascript.
loading
Mostrar: 20 | 50 | 100
Resultados 1 - 20 de 80
Filtrar
1.
PLoS One ; 18(1): e0278853, 2023.
Artigo em Inglês | MEDLINE | ID: mdl-36656850

RESUMO

Bronchopneumonia is a common respiratory disease in livestock. Mannheimia haemolytica is considered the main causative pathogen leading to lung damage in sheep, with Mycoplasma ovipneumoniae and ParaInfluenza virus type 3, combined with adverse physical and physiological stress, being predisposing factors. A balance of humoral and cellular immunity is thought to be important for protection against developing respiratory disease. In the current study, we compared the ability of the trehalose glycolipid adjuvant C18Brar (C18-alkylated brartemicin analogue) and three commercially available adjuvant systems i.e., Quil-A, Emulsigen-D, and a combination of Quil-A and aluminium hydroxide gel, to stimulate antibody and cellular immune responses to antigens from inactivated whole cells of M. haemolytica and M. ovipneumoniae in sheep. C18Brar and Emulsigen-D induced the strongest antigen-specific antibody responses to both M. haemolytica and M. ovipneumoniae, while C18Brar and Quil-A promoted the strongest antigen-specific IL-17A responses. The expression of genes with known immune functions was determined in antigen-stimulated blood cultures using Nanostring nCounter technology. The expression levels of CD40, IL22, TGFB1, and IL2RA were upregulated in antigen-stimulated blood cultures from animals vaccinated with C18Brar, which is consistent with T-cell activation. Collectively, the results demonstrate that C18Brar can promote both antibody and cellular responses, notably Th17 immune responses in a ruminant species.


Assuntos
Mannheimia haemolytica , Mycoplasma ovipneumoniae , Doenças dos Ovinos , Ovinos , Animais , Mycoplasma ovipneumoniae/genética , Trealose , Linfócitos T , Anticorpos , Imunidade
2.
Vet Res Commun ; 46(4): 1311-1318, 2022 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-35804255

RESUMO

Mycoplasma ovipneumoniae is an important etiological agent of sheep respiratory disease worldwide. Here, we describe the first isolation and draft genome sequence of M. ovipneumoniae strain USP-BR2017 retrieved from tracheobronchial lavage of a sheep showing clinical signs of respiratory disease in the Rio de Janeiro State, Brazil. The culture of tracheobronchial lavage resulted in glucose-fermenting fried egg colonies, which were identified as M. ovipneumoniae by polymerase chain reaction. The genome was sequenced using the Illumina NextSeq 2000 and de novo assembled using SPAdes. The genome of the sequenced organism presented an approximate size of 1,122,253 bp. The annotation revealed 773 coding DNA sequences (CDSs), 806 genes, three rRNAs, and 30 tRNAs. Data analysis revealed M. ovipneumoniae strain USP-BR2017 contains a few virulence genes, including the hemolysing C gene (hlyC). In addition, strain USP-BR2017 showed high identity over the 16S rRNA gene with other sheep isolates from China and United States. This first description of M. ovipneumoniae in diseased Brazilian sheep demonstrates the importance of continuous surveillance and diagnostics of pathogens causing respiratory disease in sheep in Brazil.


Assuntos
Mycoplasma ovipneumoniae , Doenças dos Ovinos , Ovinos , Animais , Mycoplasma ovipneumoniae/genética , Brasil/epidemiologia , RNA Ribossômico 16S/genética , Pulmão , Doenças dos Ovinos/diagnóstico , Genômica
3.
Viruses ; 14(7)2022 06 28.
Artigo em Inglês | MEDLINE | ID: mdl-35891403

RESUMO

Polymicrobial pneumonias occur frequently in cattle, swine, and sheep, resulting in major economic losses. Individual pathogens comprising these complex infections may be mild on their own but can instead exhibit synergism or increase host susceptibility. Two examples of such pathogens, Mycoplasma ovipneumoniae (M. ovipneumoniae) and influenza D viruses (IDVs), naturally infect domestic sheep. In sheep, the role of M. ovipneumoniae in chronic nonprogressive pneumonia is well-established, but the pathogenesis of IDV infection has not previously been studied. We utilized a specific-pathogen-free sheep flock to study the clinical response to IDV infection in naïve vs. M. ovipneumoniae-exposed lambs. Lambs were inoculated intranasally with M. ovipneumoniae or mock infection, followed after four weeks by infection with IDV. Pathogen shedding was tracked, and immunological responses were evaluated by measuring acute phase response and IDV-neutralizing antibody titers. While lamb health statuses remained subclinical, M. ovipneumoniae-exposed lambs had significantly elevated body temperatures during IDV infection compared to M. ovipneumoniae-naïve, IDV-infected lambs. Moreover, we found a positive correlation between prior M. ovipneumoniae burden, early-infection IDV shedding, and IDV-neutralizing antibody response. Our findings suggest that IDV infection may not induce clinical symptoms in domestic sheep, but previous M. ovipneumoniae exposure may promote mild IDV-associated inflammation.


Assuntos
Doenças Transmissíveis , Mycoplasma ovipneumoniae , Infecções por Orthomyxoviridae , Orthomyxoviridae , Pneumonia , Doenças dos Ovinos , Thogotovirus , Animais , Anticorpos Neutralizantes , Bovinos , Infecções por Orthomyxoviridae/veterinária , Ovinos , Suínos
4.
J Wildl Dis ; 58(3): 625-630, 2022 07 01.
Artigo em Inglês | MEDLINE | ID: mdl-35442435

RESUMO

In 2018, Mycoplasma ovipneumoniae was detected in free-ranging caribou (Rangifer tarandus grantii) and Dall's sheep (Ovis dalli dalli) in Alaska, US. Evaluation of additional nasal swabs and archived tissues for M. ovipneumoniae suggested that this bacterium was widespread geographically and temporally in populations of both species. Multilocus sequence typing of four loci identified a single, novel, apparently stable strain type of M. ovipneumoniae in 11 Dall's sheep and 15 caribou in multiple populations across Alaska sampled over a period of 15 yr (2004-19). This strain type differs from those detected to date from wild or domestic sheep (Ovis aries) or goats (Capra aegagrus hircus) tested in Alaska or the lower 48 states. Although the population health implications of this strain are unknown, it has not been associated with population-wide mortality events. The presence of this strain does not decrease the potential risk from the introduction of a pathogenic M. ovipneumoniae strain associated with severe disease in other wildlife populations; therefore, continued monitoring for signs of disease and additional strains is important.


Assuntos
Doenças das Cabras , Mycoplasma ovipneumoniae , Rena , Doenças dos Ovinos , Alaska/epidemiologia , Animais , Animais Selvagens , Cabras , Tipagem de Sequências Multilocus/veterinária , Mycoplasma ovipneumoniae/genética , Ovinos , Doenças dos Ovinos/epidemiologia
5.
Analyst ; 147(8): 1631-1640, 2022 Apr 11.
Artigo em Inglês | MEDLINE | ID: mdl-35302559

RESUMO

Mycoplasma ovipneumoniae (MO), a disease-causing pathogen with some of the highest levels of morbidity and mortality, can spread silently at the herd level. A novel alternative nanoprobe for MO was prepared using porous metal-organic frameworks (MOFs) as the scaffold and hairpin DNA with specific sequences of MO and G4 segments as the probe. This preparation was based on the strong fluorescence emission by ThT (thioflavin T) in the limitation of G-quadruplexes with a cavity structure. The use of MOFs effectively limited the folding behavior of G4 as a part of the probe to improve the defect of the strong background signal caused by the free-state G4Probe in a buffer. The results from the selectivity experiment showed that only a trace amount of the target with lower ΔG could be the "key" to the highly efficient triggering of the release behavior of the G4Probe from MOFs and the subsequent change in the fluorescence behavior of ThT. The DNA targets could be determined by observing the change in the signal. More importantly, the probe showed a low detection limit and a good linear correlation between the concentration of target DNA ranging from 10-10 M to 10-6 M not only in buffer but also in natural complex media. Moreover, the operation involved in the whole strategy was simple and the total cost was low. These findings demonstrated the value of the probe in further clinical diagnosis. This study reports the successful construction of a ΔG-sensitive sensor for MO for the first time.


Assuntos
Técnicas Biossensoriais , Quadruplex G , Mycoplasma ovipneumoniae , Benzotiazóis/química , Técnicas Biossensoriais/métodos , DNA/química , DNA/genética , Fluorescência , Corantes Fluorescentes/química , Espectrometria de Fluorescência/métodos
6.
Transbound Emerg Dis ; 69(5): e1460-e1468, 2022 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-35166453

RESUMO

A novel respiratory-associated Mycoplasma species (M. sp. nov.) of unknown clinical significance was recently identified that causes false positive results with multiple published PCR methods reported to specifically detect Mycoplasma ovipneumonaie, a well-known respiratory pathogen in small ruminants. This necessitates our objective to develop a real-time PCR (qPCR) assay for improved specificity and sensitivity, and more rapid detection and differentiation of M. ovipneumoniae and the M. sp. nov. in domestic sheep (DS) and domestic goat (DG) samples, as compared to a conventional PCR and sequencing (cPCR-seq) assay. Primers and probes were designed based on available M. ovipneumoniae 16S rRNA gene sequences in the GenBank database, and partial 16S rRNA gene sequences provided by the United States Department of Agriculture, Agricultural Research Service (USDA-ARS) for M. ovipneumoniae and M. sp. nov. USDA-ARS provided DS (n = 153) and DG (n = 194) nasal swab nucleic acid that previously tested positive for either M. ovipneumoniae (n = 117) or M. sp. nov. (n = 138), or negative for both targets (n = 92) by cPCR-seq. A host 18S rRNA gene was included as an internal control to monitor for the failure of nucleic acid extraction and possible PCR inhibition. For samples positive by cPCR-seq, qPCR agreement was 88.0% (103/117; κ = 0.81) and 89.9% (124/138; κ = 0.84) for M. ovipneumoniae and M. sp. nov., respectively; 12 of 255 (4.7%) cPCR-seq positive samples were qPCR positive for both targets. Of samples negative by cPCR for both mycoplasmas, qPCR detected M. ovipneumoniae and M. sp. nov. in 6.5% (6/92) and 4.3% (4/92), respectively. Samples with discordant results between the cPCR and sequencing assay and the new qPCR were analyzed by target sequencing; successfully sequenced samples had identity matches that confirmed the qPCR result. The increased target specificity of this qPCR is predicted to increase testing accuracy as compared to other published assays.


Assuntos
Doenças das Cabras , Mycoplasma ovipneumoniae , Mycoplasma , Doenças dos Ovinos , Animais , Doenças das Cabras/diagnóstico , Cabras , Mycoplasma/genética , Mycoplasma ovipneumoniae/genética , RNA Ribossômico 16S/genética , Reação em Cadeia da Polimerase em Tempo Real/veterinária , Ovinos , Doenças dos Ovinos/diagnóstico , Carneiro Doméstico
7.
J Wildl Dis ; 58(2): 257-268, 2022 04 01.
Artigo em Inglês | MEDLINE | ID: mdl-35104345

RESUMO

As part of a respiratory pathogen survey of Alaska wildlife, we conducted a concordance study to assess Mycoplasma ovipneumoniae detection among three different PCR assays using a total of 346 nasal swabs sampled from four species (Dall's sheep, Ovis dalli dalli; mountain goats, Oreamnos americanus; caribou, Rangifer tarandus granti; and moose, Alces alces gigas), and two taxonomic subfamilies (Bovidae subfamily Caprinae and Cervidae subfamily Capreolinae). A federal research laboratory performed two PCR assays (LM40 and intergenic spacer region [IGS]), and a state diagnostic laboratory performed the third (universal Mycoplasma [UM]). Overall concordance was good, ranging from 93% to 99%, which was probably a result of low detection rate of M. ovipneumoniae. Due to differences in positive agreement, the quality of concordance between LM40 and both IGS and UM was considered fair. However, the quality of concordance between IGS and UM was excellent. All three PCR methods detected M. ovipneumoniae in a non-Caprinae species (caribou), and the LM40-PCR assay also detected M. ovipneumoniae in additional Caprinae species. The LM40-PCR assay detected M. ovipneumoniae in a larger number of samples than did the other two assays (IGS, UM). Because of potential differences in detection rates, it is critical to consider test parameters when evaluating a host population for the presence of M. ovipneumoniae.


Assuntos
Cervos , Mycoplasma ovipneumoniae , Pneumonia por Mycoplasma , Rena , Doenças dos Ovinos , Animais , Animais Selvagens , Pneumonia por Mycoplasma/diagnóstico , Pneumonia por Mycoplasma/epidemiologia , Pneumonia por Mycoplasma/veterinária , Ruminantes , Ovinos , Doenças dos Ovinos/diagnóstico
8.
Vet Microbiol ; 265: 109334, 2022 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-35033769

RESUMO

Mycoplasma ovipneumoniae (M. ovipneumoniae) is a respiratory pathogen associated with mild to moderate respiratory disease in domestic lambs and severe pneumonia outbreaks in wild ruminants such as bighorn sheep. However, whether M. ovipneumoniae by itself causes clinical respiratory disease in domestic sheep in the absence of secondary bacterial pathogens is still unclear. The goal of our study was to better understand the role of M. ovipneumoniae as a respiratory pathogen in domestic sheep and to explore potential antibiotic treatment approaches. Therefore, we inoculated four 4-month-old, specific-pathogen-free lambs with fresh nasal wash fluids from M. ovipneumoniae-infected sheep. The lambs were monitored for M. ovipneumoniae colonization, M. ovipneumoniae-specific antibodies, clinical signs, and cellular and molecular correlates of lung inflammation for eight weeks. All lambs then were treated with gamithromycin and observed for an additional four weeks. M. ovipneumoniae inoculation resulted in stable colonization of the upper respiratory tract in all M. ovipneumoniae-inoculated, but in none of the four mock-infected control lambs. All M. ovipneumoniae-infected lambs developed a robust antibody response to M. ovipneumoniae within 2 weeks. However, we did not observe significant signs of respiratory disease, evidence of lung damage or inflammation in any of the infected lambs. Interestingly, treatment with gamithromycin, which blocked growth of the M. ovipneumoniae in vitro, failed to reduce M. ovipneumoniae colonization. These observations indicate that, in the absence of co-infections, M. ovipneumoniae caused asymptomatic colonization of the upper respiratory tract that was resistant to clearance by the host immune response and by gamithromycin treatment.


Assuntos
Mycoplasma ovipneumoniae , Doenças dos Ovinos , Carneiro da Montanha , Animais , Antibacterianos/farmacologia , Antibacterianos/uso terapêutico , Infecções Assintomáticas , Ovinos , Doenças dos Ovinos/epidemiologia
9.
BMC Vet Res ; 17(1): 327, 2021 Oct 13.
Artigo em Inglês | MEDLINE | ID: mdl-34645427

RESUMO

BACKGROUND: Bashbay sheep (Bbs) has a certain degree of resistance to Mycoplasma ovipneumoniae (Mo), however, Argali hybrid sheep (Ahs) is susceptible to Mo. To understand the molecular mechanisms underlying the difference of the susceptibility for Mo infection, RNA-sequencing technology was used to compare the transcriptomic response of the lung tissue of Mo-infected Bbs and Ahs. RESULTS: Six Bbs and six Ahs were divided into experimental group and control group respectively, all of them were experimentally infected with Mo by intratracheal injection. For collecting lung tissue samples, three Bbs and three Ahs were sacrificed on day 4 post-infection, and the others were sacrificed on day 14 post-infection. Total RNA extracted from lung tissue were used for transcriptome analyses based on high-throughput sequencing technique and bioinformatics. The results showed that 212 (146 up-regulated, 66 down-regulated) DEGs were found when comparing transcriptomic data of Bbs and Ahs at 4th dpi, besides, 311 (158 up-regulated, 153 down-regulated) DEGs were found at 14th dpi. After GO analysis, three main GO items protein glycosylation, immune response and positive regulation of gene expression were found related to Mo infection. In addition, there were 20 DEGs enriched in these above items, such as SPLUC1 (BPIFA1), P2X7R, DQA, HO-1 and SP-A (SFTPA-1). CONCLUSIONS: These selected 20 DEGs associated with Mo infection laid the foundation for further study on the underlying molecular mechanism involved in high level of resistance to Mo expressed by Bbs, meanwhile, provided deeper understandings about the development of pathogenicity and host-pathogen interactions.


Assuntos
Predisposição Genética para Doença , Pulmão/microbiologia , Infecções por Mycoplasma/veterinária , Mycoplasma ovipneumoniae/fisiologia , Doenças dos Ovinos/parasitologia , Transcriptoma , Animais , Perfilação da Expressão Gênica/veterinária , Hibridização Genética , Pulmão/metabolismo , Pneumopatias/metabolismo , Pneumopatias/microbiologia , Pneumopatias/veterinária , Infecções por Mycoplasma/microbiologia , RNA/genética , RNA/metabolismo , Ovinos , Doenças dos Ovinos/genética , Transcriptoma/genética
10.
Virulence ; 12(1): 2703-2720, 2021 12.
Artigo em Inglês | MEDLINE | ID: mdl-34678131

RESUMO

Mycoplasma ovipneumoniae (MO) is a principle causative agent of chronic respiratory disease in ruminants, including sheep, goats, and deer, posing a great threat to the ruminant industry worldwide. However, the pathogenesis of MO infection still remains not well understood and needs further clarification. Here we report a time-dependent apoptosis in cultured murine alveolar macrophage (MH-S) cell lines in response to MO infection in vitro. Mechanistically, MO infection activated apoptosis in MH-S cells through caspase-8-dependent extrinsic pathway and through tumor protein 53 (p53)- and reactive oxygen species (ROS)-dependent intrinsic mitochondrial pathways. Moreover, MO infection promoted both transcription and translation of proinflammatory cytokine genes including interleukin-1ß (IL-1ß), IL-18, and tumor necrosis factor-α (TNF-α), in a caspase-8-, p53-, and ROS-dependent manner, implying a potential link between MO-induced inflammation and apoptotic cell death. Collectively, our results suggest that MO infection induces the activation of extrinsic and intrinsic apoptotic pathways in cultured MH-S cells, which is related to upregulated expression of proinflammatory cytokines. Our findings will contribute to the elucidation of pathogenesis in MO infection and provide valuable reference for the development of new strategies for controlling MO infection.


Assuntos
Cervos , Mycoplasma ovipneumoniae , Pneumonia por Mycoplasma , Animais , Apoptose , Caspase 8/genética , Caspase 8/metabolismo , Cervos/metabolismo , Macrófagos Alveolares , Camundongos , Mycoplasma ovipneumoniae/genética , Mycoplasma ovipneumoniae/metabolismo , Pneumonia por Mycoplasma/veterinária , Espécies Reativas de Oxigênio/metabolismo , Ovinos , Proteína Supressora de Tumor p53/genética , Proteína Supressora de Tumor p53/metabolismo
11.
PLoS One ; 16(7): e0247209, 2021.
Artigo em Inglês | MEDLINE | ID: mdl-34252097

RESUMO

Mycoplasma ovipneumoniae contributes to polymicrobial pneumonia in domestic sheep. Elucidation of host genetic influences of M. ovipneumoniae nasal detection has the potential to reduce the incidence of polymicrobial pneumonia in sheep through implementation of selective breeding strategies. Nasal mucosal secretions were collected from 647 sheep from a large US sheep flock. Ewes of three breeds (Polypay n = 222, Rambouillet n = 321, and Suffolk n = 104) ranging in age from one to seven years, were sampled at three different times in the production cycle (February, April, and September/October) over four years (2015 to 2018). The presence and DNA copy number of M. ovipneumoniae was determined using a newly developed species-specific qPCR. Breed (P<0.001), age (P<0.024), sampling time (P<0.001), and year (P<0.001) of collection affected log10 transformed M. ovipneumoniae DNA copy number, where Rambouillet had the lowest (P<0.0001) compared with both Polypay and Suffolk demonstrating a possible genetic component to detection. Samples from yearlings, April, and 2018 had the highest (P<0.046) detected DNA copy number mean. Sheep genomic DNA was genotyped with the Illumina OvineHD BeadChip. Principal component analysis identified most of the variation in the dataset was associated with breed. Therefore, genome wide association analysis was conducted with a mixed model (EMMAX), with principal components 1 to 6 as fixed and a kinship matrix as random effects. Genome-wide significant (P<9x10-8) SNPs were identified on chromosomes 6 and 7 in the all-breed analysis. Individual breed analysis had genome-wide significant (P<9x10-8) SNPs on chromosomes 3, 4, 7, 9, 10, 15, 17, and 22. Annotated genes near these SNPs are part of immune (ANAPC7, CUL5, TMEM229B, PTPN13), gene translation (PIWIL4), and chromatin organization (KDM2B) pathways. Immune genes are expected to have increased expression when leukocytes encounter M. ovipneumoniae which would lead to chromatin reorganization. Work is underway to narrow the range of these associated regions to identify the underlying causal mutations.


Assuntos
Mycoplasma ovipneumoniae/fisiologia , Carneiro Doméstico/genética , Carneiro Doméstico/microbiologia , Animais , Estudo de Associação Genômica Ampla , Genótipo , Pulmão/microbiologia , Ovinos , Carneiro Doméstico/imunologia
12.
J Wildl Dis ; 57(2): 447-452, 2021 04 01.
Artigo em Inglês | MEDLINE | ID: mdl-33822157

RESUMO

A 2013 outbreak of respiratory disease in bighorn sheep from California's Mojave Desert metapopulation caused high mortality in at least one population. Subsequent PCR and strain-typing indicate widespread infection of a single strain of Mycoplasma ovipneumoniae throughout this region. Serosurvey of archived samples showed that some populations have had antibodies to M. ovipneumoniae since at least 1986, although pre-2013 strain-type data are unavailable.


Assuntos
Mycoplasma ovipneumoniae/imunologia , Pneumonia por Mycoplasma/veterinária , Carneiro da Montanha , Animais , Anticorpos Antibacterianos , California/epidemiologia , DNA Espaçador Ribossômico/genética , Clima Desértico , Pneumonia por Mycoplasma/epidemiologia , Estudos Soroepidemiológicos
13.
PLoS One ; 16(2): e0246573, 2021.
Artigo em Inglês | MEDLINE | ID: mdl-33539437

RESUMO

Mycoplasma ovipneumoniae infects both sheep and goats causing pneumonia resulting in considerable economic losses worldwide. Current diagnosis methods such as bacteriological culture, serology, and PCR are time consuming and require sophisticated laboratory setups. Here we report the development of two rapid, specific and sensitive assays; an isothermal DNA amplification using recombinase polymerase amplification (RPA) and a real-time PCR for the detection of M. ovipneumoniae. The target for both assays is a specific region of gene WP_069098309.1, which encodes a hypothetical protein and is conserved in the genome sequences of ten publicly available M. ovipneumoniae strains. The RPA assay performed well at 39°C for 20 min and was combined with a lateral flow dipstick (RPA-LFD) for easy visualization of the amplicons. The detection limit of the RPA-LFD assay was nine genome copies of M. ovipneumoniae per reaction and was comparable to sensitivity of the real-time PCR assay. Both assays showed no cross-reaction with 38 other ovine and caprine pathogenic microorganisms and two parasites of ruminants, demonstrating a high degree of specificity. The assays were validated using bronchoalveolar lavage fluid and nasal swab samples collected from sheep. The positive rate of RPA-LFD (97.4%) was higher than the real-time PCR (95.8%) with DNA as a template purified from the clinical samples. The RPA assay was significantly better at detecting M. ovipneumoniae in clinical samples compared to the real-time PCR when DNA extraction was omitted (50% and 34.4% positive rate for RPA-LFD and real-time PCR respectively). The RPA-LFD developed here allows easy and rapid detection of M. ovipneumoniae infection without DNA extraction, suggesting its potential as a point-of-care test for field settings.


Assuntos
Mycoplasma ovipneumoniae/patogenicidade , Pneumonia por Mycoplasma/microbiologia , Recombinases/metabolismo , Animais , Mycoplasma ovipneumoniae/genética , Mycoplasma ovipneumoniae/isolamento & purificação , Técnicas de Amplificação de Ácido Nucleico , Plasmídeos/genética , Pneumonia por Mycoplasma/genética , Reação em Cadeia da Polimerase em Tempo Real
14.
Vet Microbiol ; 248: 108828, 2020 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-32905961

RESUMO

Chronic non-progressive pneumonia in small ruminants caused by Mycoplasma (M.) ovipneumoniae is mainly controlled by chemotherapy. In France, during the last decade, a rise in M. ovipneumoniae cases was recorded in both sheep and goats, suggesting a possible emergence. Whether this rise is associated with antimicrobial resistance, as observed in other ruminant Mycoplasma species, has yet to be examined. The aim of the study was to characterize the diversity of M. ovipneumoniae strains circulating in France and assess their antimicrobial resistance, together with the underlying mechanisms, to help find an explanation for the increase in reported cases. The genetic diversity of 56 strains isolated between 2007 and 2018 from sheep and goats was assessed using different subtyping methods. Their susceptibility to six antimicrobial classes was profiled by estimating Minimum Inhibitory Concentrations (MICs) using an optimised agar dilution method. Resistance mechanisms were explored by sequence analysis of rRNA targets. A high genetic diversity of strains was evidenced, with consistent, marked animal-host clustering in the Hsp70 gene and whole genome sequence phylogeny. No clonal evolution could thus account for putative emergence. Apart from florfenicol, MICs were low except for a few isolates with increased values for tetracyclines, macrolides and lincosamides. Hotspot mutations in the target ribosomal gene could explain increased tetracycline MICs. Other mechanisms are suspected for macrolide-lincosamide and florfenicol resistance. The emergence of M. ovipneumoniae is thus not related to any increase in resistance or to a clonal spread. Explanations may lie in breeding practices.


Assuntos
Antibacterianos/farmacologia , Doenças das Cabras/microbiologia , Infecções por Mycoplasma/veterinária , Mycoplasma ovipneumoniae/efeitos dos fármacos , Mycoplasma ovipneumoniae/genética , Doenças dos Ovinos/microbiologia , Animais , França/epidemiologia , Variação Genética , Doenças das Cabras/epidemiologia , Cabras , Testes de Sensibilidade Microbiana , Infecções por Mycoplasma/epidemiologia , Filogenia , Ovinos , Doenças dos Ovinos/epidemiologia
15.
PLoS One ; 15(9): e0237309, 2020.
Artigo em Inglês | MEDLINE | ID: mdl-32898140

RESUMO

The relationships between host-pathogen population dynamics in wildlife are poorly understood. An impediment to progress in understanding these relationships is imperfect detection of diagnostic tests used to detect pathogens. If ignored, imperfect detection precludes accurate assessment of pathogen presence and prevalence, foundational parameters for deciphering host-pathogen dynamics and disease etiology. Respiratory disease in bighorn sheep (Ovis canadensis) is a significant impediment to their conservation and restoration, and effective management requires a better understanding of the structure of the pathogen communities. Our primary objective was to develop an easy-to-use and accessible web-based Shiny application that estimates the probability (with associated uncertainty) that a respiratory pathogen is present in a herd and its prevalence given imperfect detection. Our application combines the best-available information on the probabilities of detection for various respiratory pathogen diagnostic protocols with a hierarchical Bayesian model of pathogen prevalence. We demonstrated this application using four examples of diagnostic tests from three herds of bighorn sheep in Montana. For instance, one population with no detections of Mycoplasma ovipneumoniae (PCR assay) still had an 6% probability of the pathogen being present in the herd. Similarly, the apparent prevalence (0.32) of M. ovipneumoniae in another herd was a substantial underestimate of estimated true prevalence (0.46: 95% CI = [0.25, 0.71]). The negative bias of naïve prevalence increased as the probability of detection of testing protocols worsened such that the apparent prevalence of Mannheimia haemolytica (culture assay) in a herd (0.24) was less than one third that of estimated true prevalence (0.78: 95% CI = [0.43, 0.99]). We found a small difference in the estimates of the probability that Mannheimia spp. (culture assay) was present in one herd between the binomial sampling approach (0.24) and the hypergeometric approach (0.22). Ignoring the implications of imperfect detection and sampling variation for assessing pathogen communities in bighorn sheep can result in spurious inference on pathogen presence and prevalence, and potentially poorly informed management decisions. Our Shiny application makes the rigorous assessment of pathogen presence, prevalence and uncertainty straightforward, and we suggest it should be incorporated into a new paradigm of disease monitoring.


Assuntos
Animais Selvagens/microbiologia , Infecções por Pasteurellaceae/veterinária , Pneumonia por Mycoplasma/veterinária , Doenças dos Ovinos/epidemiologia , Carneiro da Montanha/microbiologia , Software , Animais , Teorema de Bayes , Internet , Mannheimia haemolytica/isolamento & purificação , Montana , Mycoplasma ovipneumoniae/isolamento & purificação , Infecções por Pasteurellaceae/epidemiologia , Pneumonia por Mycoplasma/epidemiologia , Prevalência , Probabilidade , Ovinos
16.
Res Vet Sci ; 133: 174-179, 2020 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-32992128

RESUMO

Clinical therapeutic and immunoregulatory effects of recombinant SPLUNC1 protein (rSPLUNC1) were evaluated in Mycoplasma ovipneumoniae (Mo)-infected Argali hybrid sheep (AHS). Group A contained six Bashibai sheep (BS) and groups B-D contained six AHS each. All sheep were manually infected with Mo. Five days post-infection, rSPLUNC1 from BS and AHS was injected intratracheally into group C and D animals; physiological saline was administered to groups A and B. Serum IL-5, IL-6, and IL-9 were quantified by ELISA. After sacrificing the sheep, lung tissues were extracted for pathological examination. The qPCR was used to quantify Mo load in the lungs and evaluate therapeutic efficacy. Serum IL-5, IL-6, and IL-9 concentrations increased during early infection stages in all groups but were significantly lower in groups A, C, and D than in group B on days 14 and 21. On day 21, IL-5 concentrations were lower in group A than in groups C and D. IL-6 concentration in groups A, C, and D was significantly lower than that in group B, and that in groups C and D was significantly lower than that in group A. Mean mycoplasma pneumonia histopathology scores were significantly lower in groups C and D than in group B, and Mo load in group C and D lung tissue decreased significantly compared to that in group B. Intratracheal injection of rSPLUNC1 into Mo-infected sheep decreased the cytokine levels and alleviated clinical symptoms with no mortality. rSPLUNC1 had significant therapeutic effects on Mo-infected AHS and can regulate pro-inflammatory cytokines.


Assuntos
Glicoproteínas/uso terapêutico , Pneumonia por Mycoplasma/veterinária , Proteínas Recombinantes/uso terapêutico , Doenças dos Ovinos/tratamento farmacológico , Animais , Ensaio de Imunoadsorção Enzimática/veterinária , Glicoproteínas/genética , Interleucinas/sangue , Pulmão/microbiologia , Pulmão/patologia , Mycoplasma ovipneumoniae , Pneumonia por Mycoplasma/tratamento farmacológico , Pneumonia por Mycoplasma/patologia , Reação em Cadeia da Polimerase em Tempo Real/veterinária , Ovinos , Doenças dos Ovinos/patologia , Resultado do Tratamento
17.
Res Vet Sci ; 132: 474-480, 2020 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-32799171

RESUMO

BACKGROUND: Mycoplasma ovipneumoniae (M. ovi) is the causative agent of chronic non-progressive pneumonia in sheep, goats, bighorn, and wild small ruminants. However, the mechanism of infection and immune response to M. ovi remain unclear. Invading microbes express lipid-associated membrane proteins (LAMPs) on the cell surface that interact with host cells to facilitate infection, and are thus the major molecules recognised by the host immune system. Upon LAMP recognition, Toll-like receptor 2 (TLR2) and NLRP3 inflammasome sense the pathogens and signalling pathways for cytokine secretion. In this study, we investigated whether M. ovi and M. ovi-derived LAMPs are immuno-biologically active compounds capable of activating mouse peritoneal macrophages and explored the underlying mechanism. RESULTS: After infection of wild-type mice with M. ovi, the expression of TLR2 and NLRP3 at the transcriptional and translational levels was determined with reverse transcription-polymerase chain reaction and flow cytometry. In addition, the cytokine levels and associated pathways were detected in infected wild-type, Tlr2-/-, and Nlrp3-/- mice via enzyme-linked immunosorbent assays and western blotting. The nuclear factor (NF)-κB and mitogen-activated protein kinase (MAPK) signalling pathways were found to mediate the expression of inflammatory cytokines in M. ovi or M. ovi-derived LAMP-infected peritoneal macrophages, and cytokines were not induced in Tlr2-/- and/or Nlrp3-/- macrophages. CONCLUSION: Host cytokine production is activated in response to M. ovi-derived LAMPs through the NF-κB and MAPK signalling pathway via TLR2.


Assuntos
Lipídeos/química , Macrófagos Peritoneais/efeitos dos fármacos , Macrófagos Peritoneais/metabolismo , Mycoplasma ovipneumoniae/química , Receptor 2 Toll-Like/metabolismo , Animais , Secreções Corporais/metabolismo , Citocinas/metabolismo , Proteínas de Membrana , Camundongos , Proteínas Quinases Ativadas por Mitógeno/metabolismo , Mycoplasma ovipneumoniae/metabolismo , NF-kappa B/metabolismo , Transdução de Sinais , Receptor 2 Toll-Like/genética
18.
J Bacteriol ; 202(20)2020 09 23.
Artigo em Inglês | MEDLINE | ID: mdl-32778560

RESUMO

Mycoplasma ovipneumoniae belongs to Mycoplasma, a genus containing the smallest self-replicating microorganisms, and causes infectious pleuropneumonia in goats and sheep. Nucleotide-binding oligomerization domain-containing protein (NOD2), an intracellular pattern recognition receptor, interacts with muramyl dipeptide (MDP) to recognize bacterial peptidoglycans and is involved in autophagy induction. However, there have been no reports about NOD recognition of mycoplasmas or M. ovipneumoniae-induced autophagy. In this study, we sought to determine the role of NOD2 in M. ovipneumoniae-induced autophagy using Western blotting, immunofluorescence, real-time PCR (RT-PCR), and color-changing unit (CCU) analysis. M. ovipneumoniae infection markedly increased NOD2 but did not increase NOD1 expression in RAW 264.7 cells. Treating RAW 264.7 cells with MDP significantly increased colocalization of M. ovipneumoniae and LC3, whereas treatment with NOD inhibitor, NOD-IN-1, decreased colocalization of M. ovipneumoniae and LC3. Furthermore, suppressing NOD2 expression with small interfering RNA (siRNA)-NOD2 failed to trigger M. ovipneumoniae-induced autophagy by detecting autophagy markers Atg5, beclin1, and LC3-II. In addition, M. ovipneumoniae infection significantly increased the phosphorylated c-Jun NH2-terminal kinase (p-JNK)/JNK, p-Bcl-2/Bcl-2, beclin1, Atg5, and LC3-II ratios in RAW 264.7 cells. Treatment with JNK inhibitor, SP600126, or siRNA-NOD2 did not increase this reaction. These findings suggested that M. ovipneumoniae infection activated NOD2, and both NOD2 and JNK pathway activation promoted M. ovipneumoniae-induced autophagy. This study provides new insight into the NOD2 reorganization mechanism and the pathogenesis of M. ovipneumoniae infection.IMPORTANCEM. ovipneumoniae, which lacks a cell wall, causes infectious pleuropneumonia in goats and sheep. In the present study, we focused on the interaction between NOD and M. ovipneumoniae, as well as its association with autophagy. We showed for the first time that NOD2 was activated by M. ovipneumoniae even when peptidoglycans were not present. We also observed that both NOD2 and JNK pathway activation promoted M. ovipneumoniae-induced autophagy.


Assuntos
Autofagia , Sistema de Sinalização das MAP Quinases , Macrófagos/microbiologia , Mycoplasma ovipneumoniae/patogenicidade , Proteína Adaptadora de Sinalização NOD2/metabolismo , Animais , Camundongos , Fosforilação , Células RAW 264.7
19.
PLoS One ; 15(7): e0214497, 2020.
Artigo em Inglês | MEDLINE | ID: mdl-32639963

RESUMO

The Bashbay sheep (Ovis aries), an indigenous breed of Xinjiang, China, has many excellent characteristics. It is resistant to Mycoplasma ovipneumoniae infection, the causative agent of mycoplasma ovipneumonia, a chronic respiratory disease that is harmful to the sheep industry. To date, knowledge regarding the mechanisms responsible for M. ovipneumoniae pathogenesis in scant. Herein, we report the results of transcriptome profiling of lung tissues from Bashbay sheep experimentally infected with an M. ovipneumoniae strain at 4 and 14 days post-infection, in comparison to mock-infected animals (0 d). Transcriptome profiling was performed by deep RNA sequencing, using the Illumina platform. The analysis of differentially expressed genes was performed to determine concomitant gene-specific temporal patterns of mRNA expression in the lungs after M. ovipneumoniae infection. We found 1048 differentially expressed genes (575 up-regulated, 473 down-regulated) when comparing transcriptomic data at 4 and 0 days post-infection, and 2823 (1362 up-regulated, 1461 down-regulated) when comparing 14 versus 0 days post-infection. Kyoto Encyclopedia of Genes and Genomes pathway analysis showed that the differentially expressed genes at 4 and 14 versus 0 days post-infection were enriched in 245 and 287 pathways, respectively, and the Toll-like receptor (TLR) signaling pathway was considered most closely related to MO infection (p < 0.01). Two pathways (LAMP-TLR2/TLR6-MyD88-MKK6-AP1-IL1B and LAMP-TLR8MyD88-IRF5-RANTES) were identified based on the TLR signaling pathway from differentially expressed genes related M. ovipneumoniae infection. Gene Ontology analysis showed that differentially expressed genes in different groups were enriched for 1580 and 4561 terms, where those most closely related to M. ovipneumoniae infection are positive regulators of inflammatory responses (p < 0.01). These results could aid in understanding how M. ovipneumoniae infection progresses in the lungs and may provide useful information regarding key regulatory pathways.


Assuntos
Pulmão/metabolismo , Pneumonia por Mycoplasma/patologia , Análise de Sequência de RNA/métodos , Doenças dos Ovinos/patologia , Transcriptoma , Animais , Regulação para Baixo , Mycoplasma ovipneumoniae/isolamento & purificação , Mycoplasma ovipneumoniae/patogenicidade , Pneumonia por Mycoplasma/genética , Pneumonia por Mycoplasma/veterinária , RNA Mensageiro/química , RNA Mensageiro/metabolismo , Ovinos , Doenças dos Ovinos/genética , Doenças dos Ovinos/metabolismo , Transdução de Sinais/genética , Fatores de Tempo , Receptores Toll-Like/genética , Receptores Toll-Like/metabolismo , Regulação para Cima
20.
Res Vet Sci ; 132: 57-68, 2020 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-32505020

RESUMO

BACKGROUND: An experiment was conducted to reveal why the Argali hybrid sheep are susceptible to Mycoplasma ovipneumoniae infection, the causative agent of mycoplasma ovipneumonia, a chronic respiratory disease that is harmful to the sheep industry. RESULTS: After nine Argali hybrid sheep, divided into three groups, were experimentally infected with an M. ovipneumoniae strain at 0, 4 and 14 days, transcriptome profiling of lung tissues was performed by deep RNA sequencing, using the Illumina platform. Analysis of differentially expressed genes was performed to determine concomitant gene-specific temporal patterns of mRNA expression in the lungs after M. ovipneumoniae infection. 156 differentially expressed genes (44 up-regulated, 112 down-regulated) were found when comparing transcriptomic data at 4 and 0 days post-infection, and 367 (35 up-regulated, 332 down-regulated) when comparing 14 versus 0 days post-infection. Kyoto Encyclopedia of Genes and Genomes pathway analysis showed that the differentially expressed genes at 4 and 14 versus 0 days post-infection were enriched in 109 and 150 pathways, respectively, and the Primary immunodeficiency pathway was considered most closely related to MO infection (p < .01). Hyper-IgM syndrome was identified based on the B-cell Immunodeficiency signaling pathway from differentially expressed genes related to M. ovipneumoniae infection. Gene Ontology analysis showed that differentially expressed genes in different groups were enriched for 497 and 928 terms, where those most closely related to M. ovipneumoniae infection are ciliated motor damage (p < .01). CONCLUSIONS: The situation that ciliary movement is significantly inhibited and B cells in immunodeficiency are possibly the most important reason why Argali hybrid sheep are susceptible to MO.


Assuntos
Regulação da Expressão Gênica , Pulmão/imunologia , Mycoplasma ovipneumoniae/fisiologia , Pneumonia por Mycoplasma/veterinária , Doenças dos Ovinos/imunologia , Transcriptoma , Animais , Feminino , Hibridização Genética , Pulmão/microbiologia , Masculino , Pneumonia por Mycoplasma/imunologia , Pneumonia por Mycoplasma/microbiologia , RNA-Seq/veterinária , Ovinos , Doenças dos Ovinos/microbiologia , Carneiro Doméstico
SELEÇÃO DE REFERÊNCIAS
DETALHE DA PESQUISA
...