Introduction: Streptococcus pneumoniae is the most common cause of bacterial meningitis and meningoencephalitis in humans. The bacterium produces numerous virulence determinants, among them hydrogen peroxide (H2O2) and pneumolysin (Ply), which contribute to bacterial cytotoxicity. Microglia, the resident phagocytes in the brain, are distinct from other macrophages, and we thus compared their susceptibility to pneumococcal toxicity and their ability to phagocytose pneumococci with those of bone marrow-derived macrophages (BMDM).
View Article and Find Full Text PDFMarine mammals are sentinel species representing the "health" of our oceans on which we are dependent. There are many threats to marine mammals including infectious diseases that increase with climate change and pollution of the marine environment. Streptococcus phocae has frequently been isolated from diseased or dead marine mammals.
View Article and Find Full Text PDFPathogens
December 2023
is a porcine and zoonotic pathogen in the upper respiratory tract, expressing different capsular serotypes and virulence-associated factors. Given its genomic and phenotypic diversity, the virulence potential of cannot be attributed to a single factor. Since strong inflammatory response is a hallmark of infection, the objective of this study was to investigate the differences in transcriptional host responses to two serotype 2 and one serotype 9 strains.
View Article and Find Full Text PDFis one of the most important porcine pathogens causing Glaesser's disease. Neutrophil granulocytes are the major counteracting cell type of the innate immune system, which contribute to the host defense by phagocytosis or the formation of neutrophil extracellular traps (NETs). Recently, NET-formation has been shown to facilitate the survival of bacteria from the family.
View Article and Find Full Text PDFStreptococcus suis, a common member of the porcine respiratory microbiota, can cause life-threatening diseases in pigs as well as humans. A previous study identified the gene trpX as conditionally essential for in vivo survival by intrathecal infection of pigs with a transposon library of S. suis strain 10.
View Article and Find Full Text PDFHighly pathogenic avian influenza viruses of the H5N8 subtype have been circulating in Europe and Asia since 2016, causing huge economic losses to the poultry industry. A new wave of H5Nx infections has begun in 2020. The viruses mainly infect wild birds and waterfowl; from there they spread to poultry and cause diseases.
View Article and Find Full Text PDFThe Gram-negative, obligate intracellular bacterium is the causative organism of the zoonosis Q fever and is known for its resistance toward various intra- and extracellular stressors. Infected ruminants such as cattle, sheep, and goats can shed the pathogen in their milk. Pasteurization of raw milk was introduced for the inactivation of and other milk-borne pathogens.
View Article and Find Full Text PDFStreptococcus suis, an emerging zoonotic pathogen, causes invasive diseases in pigs, including sepsis, meningitis, endocarditis, pneumonia, and arthritis. Importantly, similar pathologies are reported in human S. suis infections.
View Article and Find Full Text PDFpathogenicity island (SPI) 2 type three secretion system (T3SS)-mediated effector molecules facilitate bacterial survival in phagocytes but their role in the intestinal epithelium remains ill-defined. Using our neonatal murine infection model in combination with SPI2 reporter technology and RNA-Seq of sorted primary enterocytes, we demonstrate expression of SPI2 effector molecules by intraepithelial Typhimurium . Typhimurium).
View Article and Find Full Text PDFA vaccine protecting against different Streptococcus suis serotypes is highly needed in porcine practice to improve animal welfare and reduce the use of antibiotics. We hypothesized that immunogens prominently recognized by convalescence sera but significantly less so by sera of susceptible piglets are putative protective antigens. Accordingly, we investigated immunogenicity and protective efficacy of a multicomponent vaccine including six main conserved immunogens, namely SSU0934, SSU1869, SSU0757, SSU1950, SSU1664 and SSU0187.
View Article and Find Full Text PDF() is an important opportunistic pathogen, which can cause septicemia and meningitis in pigs and humans. Previous observations in -infected pigs revealed lesions at the choroid plexus (CP). experiments with primary porcine CP epithelial cells (PCPEC) and human CP epithelial papilloma (HIBCPP) cells demonstrated that can invade and traverse the CP epithelium, and that the CP contributes to the inflammatory response cytokine expression.
View Article and Find Full Text PDFis a common pathogen colonising the respiratory tract of pigs. It can cause meningitis, sepsis and pneumonia leading to economic losses in the pig industry worldwide. Cyclooxygenase-2 (COX-2) and its metabolites play an important regulatory role in different biological processes like inflammation modulation and immune activation.
View Article and Find Full Text PDFMarine mammals are sentinels for the marine ecosystem and threatened by numerous factors including infectious diseases. One of the most frequently isolated bacteria are beta-hemolytic streptococci. However, knowledge on ecology and epidemiology of streptococcal species in marine mammals is very limited.
View Article and Find Full Text PDFSerotyping is the most common method to characterize field isolates of Actinobacillus (A.) pleuropneumoniae, the etiological agent of porcine pleuropneumonia. Based on serology, many farms seem to be infected and antibodies against a wide variety of serovars are detectable, but, so far it is unknown to what degree respective serovars contribute to outbreaks of clinical manifest disease.
View Article and Find Full Text PDFPasteurella (P.) multocida is a zoonotic pathogen, which is able to cause respiratory disorder in different hosts. In cattle, P.
View Article and Find Full Text PDFGlaesserella parasuis is an important pathogen in swine production. It acts as a primary pathogen in systemic Glässer´s disease and as a secondary pathogen in Porcine Respiratory Disease Complex. In this study, a collection of 308 isolates from carrier animals and individuals with respiratory or Glässer´s disease isolated 2012-2019 in Germany was analysed.
View Article and Find Full Text PDFis a zoonotic agent causing meningitis in pigs and humans. Neutrophils, as the first line of defense against infections, release neutrophil extracellular traps (NETs) to entrap pathogens. In this study, we investigated the role of the secreted nuclease A of (SsnA) as a NET-evasion factor in vivo and in vitro.
View Article and Find Full Text PDFis a swine pathogen and a zoonotic agent afflicting people in close contact with infected pigs or pork meat. Sporadic cases of human infections have been reported worldwide. In addition, outbreaks emerged in Asia, making this bacterium a primary health concern in this part of the globe.
View Article and Find Full Text PDFActinobacillus (A.) pleuropneumoniae is one of the most important respiratory pathogens in global pig production. Antimicrobial treatment and vaccination provide only limited protection, but genetic disease resistance is a very promising alternative for sustainable prophylaxis.
View Article and Find Full Text PDF() is a major cause of economic losses in the pig industry worldwide and is an emerging zoonotic pathogen. One important virulence-associated factor is suilysin (SLY), a toxin that belongs to the family of cholesterol-dependent pore-forming cytolysins (CDC). However, the precise role of SLY in host-pathogen interactions is still unclear.
View Article and Find Full Text PDFActinobacillus pleuropneumoniae (A.pp) causes severe pneumonia associated with enormous economic loss in pigs. Peracute diseased pigs die in <24 h with pneumonia.
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