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Veterinary Microbiology Dec 2019Mannheimia haemolytica colonizes the nasopharynx of cattle and can cause severe fibrinous pleuropneumonia. IgA proteases are metalloendopeptidases released by bacteria...
Mannheimia haemolytica colonizes the nasopharynx of cattle and can cause severe fibrinous pleuropneumonia. IgA proteases are metalloendopeptidases released by bacteria that cleave IgA, enhancing colonization of mucosa. The objectives of these studies were to characterize M. haemolytica IgA1 and IgA2 proteases in vitro and in silico, to clone and sequence the genes for these proteases, and to demonstrate immunogenicity of components of the entire IgA protease molecule. Both IgA protease genes were cloned, expressed, and sequenced. Sequences were compared to other published sequences. Components were used to immunize mice to determine immunogenicity. Sera from healthy cattle and cattle that recovered from respiratory disease were examined for antibodies to IgA proteases. In order to assay the cleavage of bovine IgA with IgA1 protease, M. haemolytica culture supernatant was incubated with bovine IgA. Culture supernatant cleaved purified bovine IgA in the presence of ZnCl. Both IgA proteases contain three domains, 1) IgA peptidase, 2) PL1_Passenger_AT and 3) autotransporter. IgA1 and IgA2 peptidases have molecular weights of 96.5 and 87 kDa, respectively. Convalescent bovine sera with naturally high anti-M. haemolytica antibody titers had high antibodies against all IgA1 & IgA2 protease components. Mouse immunizations indicated high antibodies to the IgA peptidases and autotransporters but not to PL1_Passenger_AT. These data indicate that M. haemolytica produces two IgA proteases that are immunogenic, can cleave bovine IgA, and are produced in vivo, as evidenced by antibodies in convalescent bovine sera. Further studies could focus on IgA protease importance in pathogenesis and immunity.
Topics: Animals; Antibodies, Bacterial; Antigens, Bacterial; Cattle; Cloning, Molecular; Enzyme-Linked Immunosorbent Assay; Immunoglobulin A; Mannheimia haemolytica; Mice; Mice, Inbred BALB C; Recombinant Proteins; Serine Endopeptidases
PubMed: 31767097
DOI: 10.1016/j.vetmic.2019.108487 -
The Veterinary Clinics of North... Jul 2020The bacteria Mannheimia haemolytica and Pasteurella multocida contribute to bovine respiratory disease (BRD), which is often managed with antimicrobials. Antimicrobial... (Review)
Review
The bacteria Mannheimia haemolytica and Pasteurella multocida contribute to bovine respiratory disease (BRD), which is often managed with antimicrobials. Antimicrobial resistance in these bacteria has been rare, but extensively drug-resistant strains have recently become common. Routine antimicrobial use may be driving this resistance. Resistance spread is caused in part by propagation of strains harboring integrative conjugative elements. The impact of antimicrobial resistance on treatment outcomes is not clear, but clinical observations suggest that response to first treatment has decreased over time, possibly because of resistance. Clinicians should consider antimicrobial resistance when designing BRD treatment and control programs.
Topics: Animals; Anti-Bacterial Agents; Bovine Respiratory Disease Complex; Cattle; Mannheimia haemolytica; Microbial Sensitivity Tests; Pasteurella multocida
PubMed: 32327253
DOI: 10.1016/j.cvfa.2020.02.001 -
BMC Veterinary Research Jan 2022Mannheimia haemolytica is commonly associated with respiratory disease in cattle worldwide as a cause of fibrinous pneumonia, bronchopneumonia and pleuritis. M....
BACKGROUND
Mannheimia haemolytica is commonly associated with respiratory disease in cattle worldwide as a cause of fibrinous pneumonia, bronchopneumonia and pleuritis. M. haemolytica is further subdivided into 12 serovars, however not all are considered to be pathogenic in cattle. The study aim was to determine the most common serovars of M. haemolytica associated with respiratory disease in cattle in Great Britain, which is currently unknown and could be useful information for clinicians when considering preventative strategies.
RESULTS
One hundred four M. haemolytica isolates isolated from bovine clinical pathology and post-mortem samples from pneumonia cases between 2016 and 2018 were tested using a multiplex PCR assay to identify M. haemolytica serovars A1, A2 and A6. 46 isolates (44.2%) typed as M. haemolytica serovar A1, 31 (29.8%) as M. haemolytica serovar A2 and 18 isolates (17.3%) as M. haemolytica serovar A6. Nine isolates (8.7%) were not A1, A2 or A6 so were considered to belong to other serovars or were not typable.
CONCLUSION
This study highlights the importance of M. haemolytica serovars other than A1 which may be responsible for respiratory disease in cattle and could help guide the veterinarian when making choices on preventative vaccination programmes.
Topics: Animals; Bronchopneumonia; Cattle; Cattle Diseases; Mannheimia haemolytica; Pleurisy; Serogroup; United Kingdom
PubMed: 34980139
DOI: 10.1186/s12917-021-03121-3 -
Microbial Pathogenesis Nov 2022Mannheimia haemolytica is the causal agent of the shipping fever in bovines and produces high economic losses worldwide. This bacterium possesses different virulence...
Mannheimia haemolytica is the causal agent of the shipping fever in bovines and produces high economic losses worldwide. This bacterium possesses different virulence attributes to achieve a successful infection. One of the main virulence factors expressed by a pathogen is through adhesion molecules; however, the components participating in this process are not totally known. The present work identified a M. haemolytica 41 kDa outer membrane protein (Omp) that participates in bacterial adhesion. This protein showed 100% identity with the OmpH from M. haemolytica as determined by mass spectrometry and it interacts with sheep fibrinogen. The 41 kDa M. haemolytica OmpH interacts with bovine monocytes; a previous incubation of M. haemolytica with a rabbit hyperimmune serum against this Omp diminished 45% cell adhesion. The OmpH was recognized by serum from bovines affected by acute or chronic pneumonia, indicating its in vivo expression; moreover, it showed immune cross-reaction with the serum of rabbit infected with Pasteurella multocida. The OmpH is present in biofilms and previous incubation of M. haemolytca with rabbit serum against this protein diminished biofilm, indicating this protein's participation in biofilm formation. M. haemolytica OmpH is proposed as a relevant immunogen in bovine pneumonia protection.
Topics: Cattle; Animals; Sheep; Rabbits; Mannheimia haemolytica; Fibronectins; Fibrinogen; Pasteurella multocida; Biofilms; Virulence Factors; Bacterial Outer Membrane Proteins
PubMed: 36126788
DOI: 10.1016/j.micpath.2022.105788 -
Veterinary Microbiology Aug 2023Amongst the bacterial pathogens associated with the bovine respiratory disease syndrome (BRD) in cattle are Mannheimia haemolytica and Mycoplasma bovis. The interaction...
Amongst the bacterial pathogens associated with the bovine respiratory disease syndrome (BRD) in cattle are Mannheimia haemolytica and Mycoplasma bovis. The interaction between these two pathogens has not been investigated before; thus, there are gaps in the knowledge of why and how a previous infection with M. haemolytica allows the development of M. bovis-related lesions. We hypothesized that upon M. haemolytica infection, inflammatory products are produced in the lung and that these inflammatory products stimulate M. bovis to produce proteases and lipases that degrade lipids and proteins important for lung function. In this work, we identified several M. bovis proteases and lipases whose expression was modulated by M. haemolytica products in vitro. We performed co-infection animal challenges to develop a model to test vaccine protection. A prior exposure to BHV-1 followed by infection with M. bovis and M. haemolytica resulted in severe pathology and the BHV-1 infection was abandoned. When M. bovis and M. haemolytica were introduced into the lungs by bronchoscopy, we found that M. haemolytica resulted in worsening of the respiratory disease caused by M. bovis. We performed a proof-of-concept trial where animals were immunized with the M. bovis proteins identified in this study and challenged with both pathogens. Despite detecting significant humoral immune responses to the antigens, the experimental vaccine failed to protect against M. bovis disease.
Topics: Animals; Cattle; Bacteria; Cattle Diseases; Mannheimia haemolytica; Mycoplasma bovis; Respiratory Tract Diseases; Proof of Concept Study
PubMed: 37276814
DOI: 10.1016/j.vetmic.2023.109793 -
Veterinary Journal (London, England :... Feb 2021In the Dutch national surveillance system, outbreaks of fatal infections by Mannheimia haemolytica (M. haemolytica) in dairy cows and veal calves have become apparent in...
In the Dutch national surveillance system, outbreaks of fatal infections by Mannheimia haemolytica (M. haemolytica) in dairy cows and veal calves have become apparent in recent years. These observations prompted an in-depth analysis of available pathology data over the period 2004-2018 to investigate changes in the occurrence and/or expression of M. haemolytica-associated cattle disease. With multilevel logistic regression models, time trends were identified and corrected for farm, season, pathologist and region. Deaths associated with M. haemolytica infection increased over time with dairy cows and veal calves diagnosed with fatal M. haemolytica infections 1.5 and 1.4 times more frequently every following 3-year period between 2004 and 2018, respectively. M. haemolytica-associated disease showed two distinct disease presentations: acute pleuropneumonia in dairy cows and polyserositis in veal calves. The prevalence of both disease presentations with M. haemolytica confirmed increased in each 3-year time period between 2004 and 2018, with an odds ratio (OR) of 1.5 for acute pleuropneumonia in dairy cows and an OR of 1.7 for polyserositis in veal calves. No change was found for M. haemolytica-associated disease in dairy calves. Although M. haemolytica is considered an opportunist bovine pathogen, and the presence of primary pathogens such as BHV-1, BVDV and Mycoplasma species was not completely ruled out in our study, substantial evidence is provided to indicate infections with M. haemolytica were the most likely cause of death. M. haemolytica-associated diseases occurred more often in October-June than July-September, and were detected more often in necropsied animals from the North, South and East Netherlands than the West Netherlands.
Topics: Animals; Cattle; Cattle Diseases; Mannheimia haemolytica; Netherlands; Pasteurellosis, Pneumonic; Prevalence
PubMed: 33468303
DOI: 10.1016/j.tvjl.2020.105576 -
Infection and Immunity Jun 2019The Gram-negative bacterium is the primary bacterial species associated with bovine respiratory disease (BRD) and is responsible for significant economic losses to...
The Gram-negative bacterium is the primary bacterial species associated with bovine respiratory disease (BRD) and is responsible for significant economic losses to livestock industries worldwide. Healthy cattle are frequently colonized by commensal serotype A2 strains, but disease is usually caused by pathogenic strains of serotype A1. For reasons that are poorly understood, a transition occurs within the respiratory tract and a sudden explosive proliferation of serotype A1 bacteria leads to the onset of pneumonic disease. Very little is known about the interactions of with airway epithelial cells of the respiratory mucosa which might explain the different abilities of serotype A1 and A2 strains to cause disease. In the present study, host-pathogen interactions in the bovine respiratory tract were mimicked using a novel differentiated bovine bronchial epithelial cell (BBEC) infection model. In this model, differentiated BBECs were inoculated with serotype A1 or A2 strains of and the course of infection followed over a 5-day period by microscopic assessment and measurement of key proinflammatory mediators. We have demonstrated that serotype A1, but not A2, invades differentiated BBECs by transcytosis and subsequently undergoes rapid intracellular replication before spreading to adjacent cells and causing extensive cellular damage. Our findings suggest that the explosive proliferation of serotype A1 that occurs within the bovine respiratory tract prior to the onset of pneumonic disease is potentially due to bacterial invasion of, and rapid proliferation within, the mucosal epithelium. The discovery of this previously unrecognized mechanism of pathogenesis is important because it will allow the serotype A1-specific virulence determinants responsible for invasion to be identified and thereby provide opportunities for the development of new strategies for combatting BRD aimed at preventing early colonization and infection of the bovine respiratory tract.
Topics: Animals; Bronchi; Cattle; Epithelial Cells; Mannheimia haemolytica; Pasteurellosis, Pneumonic; Respiratory System; Virulence
PubMed: 30962401
DOI: 10.1128/IAI.00078-19 -
The Journal of Antimicrobial... Sep 2023
Topics: Mannheimia haemolytica; Anti-Bacterial Agents; Drug Resistance, Bacterial; Macrolides; Pasteurella multocida
PubMed: 37533327
DOI: 10.1093/jac/dkad209 -
Veterinary Research 2005Mannheimia haemolytica induced pneumonias are only observed in goats, sheep and cattle. The bacterium produces several virulence factors,whose principal ones are... (Review)
Review
Mannheimia haemolytica induced pneumonias are only observed in goats, sheep and cattle. The bacterium produces several virulence factors,whose principal ones are lipopolysaccharide and leukotoxin. The latter is cytotoxic only for ruminant leukocytes, a phenomenon that is correlated with its ability to bind and interact with the ruminant beta2-integrin Lymphocyte Function-associated Antigen 1. This paper globally reviews all the information available on host-pathogen interactions underlying respiratory mannheimiosis (formerly pasteurellosis), from the stable and the Petri dish to the biochemical cascade of events triggered by the leukotoxin inside ruminant leukocytes. One conclusion can be made: the most widespread cattle respiratory disease with the most important impact on beef production worldwide, is probably due to a tiny ruminant-specific focal variation in the CD18- and/or CD11a-expressing genes.
Topics: Animals; Bacterial Toxins; Cattle; Exotoxins; Lipopolysaccharides; Mannheimia haemolytica; Pasteurellosis, Pneumonic; Virulence Factors
PubMed: 15720968
DOI: 10.1051/vetres:2004065 -
Animal Health Research Reviews Dec 2020Bovine respiratory disease (BRD) is the most common cause of morbidity and mortality in North American beef cattle. In recent years, isolation of strains of Mannheimia...
Bovine respiratory disease (BRD) is the most common cause of morbidity and mortality in North American beef cattle. In recent years, isolation of strains of Mannheimia haemolytica that are resistant to multiple different classes of antimicrobials has become commonplace. New research would suggest that the routine use of antimicrobials by some cattle operations might be driving emerging resistance patterns, with the majority of the spread observed due to propagation of strains of M. haemolytica that have acquired integrative conjugative elements. To date, there is little information evaluating the impact of antimicrobial resistance on clinical outcome in cattle with BRD.
Topics: Animals; Anti-Bacterial Agents; Bovine Respiratory Disease Complex; Cattle; Drug Resistance, Bacterial; Mannheimia haemolytica; Prevalence
PubMed: 33261715
DOI: 10.1017/S1466252320000109