Synthetic antimicrobial peptides Bac-5, BMAP-28, and Syn-1 can inhibit bovine respiratory disease pathogens .

Mass treatment with antibiotics at arrival has been the mainstay for bovine respiratory disease (BRD) control but there is an increase in antimicrobial-resistant bacteria being shed from treated cattle. BRD is a disease complex that results from the interaction of viruses or bacteria and susceptible animals with inappropriate immunity. With bacteria being the only feasibly treatable agent and the emergence of antimicrobial resistance, decreased efficacy of commonly used antibiotics could threaten livestock health.

L-arginine supplementation abrogates hypoxia-induced virulence of in a murine diabetic pressure wound model.

Diabetic foot ulcers (DFUs) are the most common complications of diabetes resulting from hyperglycemia leading to ischemic hypoxic tissue and nerve damage. is the most frequently isolated bacteria from DFUs and causes severe necrotic infections leading to amputations with a poor 5-year survival rate. However, very little is known about the mechanisms by which dominantly colonizes and causes severe disease in DFUs.

Stimulation Strength Determined by Superantigen Dose Controls Subcellular Localization of FOXP3 Isoforms and Suppressive Function of CD4+CD25+FOXP3+ T Cells.

Staphylococcal superantigens induce massive activation of T cells and inflammation, leading to toxic shock syndrome. Paradoxically, increasing evidence indicates that superantigens can also induce immunosuppression by promoting regulatory T cell (Treg) development. In this study, we demonstrate that stimulation strength plays a critical role in superantigen-mediated induction of immunosuppressive human CD4+CD25+FOXP3+ T cells.

Assessment of accredited veterinary diagnostic laboratory use of breakpoints for canine and feline infections in the United States and Canada.

The objective of this study was to assess the use of breakpoints in antibiotic susceptibility testing among veterinary diagnostic laboratories in the United States and Canada. An eight-question survey was conducted via phone and email to determine how often laboratories use breakpoints consistent with published guidelines in wounds, lower urinary tract infections and upper urinary tract infections (pyelonephritis) involving , both in dogs and cats, for a total of 6 different hypothetical clinical scenarios. Nineteen veterinary diagnostic laboratories that perform antibiotic susceptibility testing on samples from dogs and cats in the United States or Canada and were accredited by the American Association of Veterinary Laboratory Diagnosticians (AAVLD) responded to the survey between January 15th and September 15th, 2022.

Multiclonal human origin and global expansion of an endemic bacterial pathogen of livestock.

Most new pathogens of humans and animals arise via switching events from distinct host species. However, our understanding of the evolutionary and ecological drivers of successful host adaptation, expansion, and dissemination are limited. is a major bacterial pathogen of humans and a leading cause of mastitis in dairy cows worldwide.

The Group B Streptococcal Adhesin BspC Interacts with Host Cytokeratin 19 To Promote Colonization of the Female Reproductive Tract.

Streptococcus agalactiae, otherwise known as Group B Streptococcus (GBS), is an opportunistic pathogen that vaginally colonizes approximately one third of healthy women. During pregnancy, this can lead to infection, resulting in premature rupture of membranes, chorioamnionitis, and stillbirths. Furthermore, GBS causes serious infection in newborns, including sepsis, pneumonia, and meningitis.

Does swab type matter? Comparing methods for Mannheimia haemolytica recovery and upper respiratory microbiome characterization in feedlot cattle.

Background: Bovine respiratory disease (BRD) is caused by interactions among host, environment, and pathogens. One standard method for antemortem pathogen identification in cattle with BRD is deep-guarded nasopharyngeal swabbing, which is challenging, costly, and waste generating. The objective was to compare the ability to recover Mannheimia haemolytica and compare microbial community structure using 29.

Effect of Treated Time of Hydrothermal Etching Process on Oxide Layer Formation and Its Antibacterial Properties.

Inspired by natural materials, we developed an antibacterial surface on titanium (Ti) using hydrothermal etching techniques and examined the effect of treated time on oxide layer formation, its antibacterial properties, and surface defects. Hydrothermal etching was conducted on Grade 2 commercially pure Ti immersed in 5M NaOH at 250 °C during a range of time of 0-12 h. Nanopillars generated on the surface had ~100 nm thickness, which resulted in decreased attachment and rupturing of the attached bacteria.

Contribution of Puma to Inflammatory Resolution During Early Pneumococcal Pneumonia.

Apoptosis of cells at the site of infection is a requirement for shutdown of inflammatory signaling, avoiding tissue damage, and preventing progression of sepsis. and mice were challenged with TIGR4 strain pneumococcus and cytokines were quantitated from lungs and blood using a magnetic bead panel analysis. mice exhibited higher lung and blood cytokine levels of several major inflammatory cytokines, including IL-6, G-CSF, RANTES, IL-12, IFN-ϒ, and IP-10.

Role of Glucose-6-Phosphate in Metabolic Adaptation of Staphylococcus aureus in Diabetes.

Diabetic foot ulcer (DFU) is the most common and costly sequela of diabetes mellitus, often leading to lower-extremity amputation with poor 5-year survival rates. Staphylococcus aureus is the most prevalent pathogen isolated from DFU, suggesting adaptation of S. aureus to the unique metabolic conditions of diabetes.

Pneumococcal surface adhesion A protein (PsaA) interacts with human Annexin A2 on airway epithelial cells.

(pneumococcus) is a normal colonizer of the human nasopharynx capable of causing serious invasive disease. Since colonization of the nasopharynx is a prerequisite for progression to invasive diseases, the development of future protein-based vaccines requires an understanding of the intimate interaction of bacterial adhesins with host receptors. In this study, we identified that pneumococcal surface adhesin A (PsaA), a highly conserved pneumococcal protein known to play an important role in colonization of pneumococcus, can interact with Annexin A2 (ANXA2) on Detroit 562 nasopharyngeal epithelial cells.

Responses to chemical cross-talk between the Mycobacterium ulcerans toxin, mycolactone, and Staphylococcus aureus.

Buruli ulcer is a neglected tropical disease caused by the environmental pathogen, Mycobacterium ulcerans whose major virulence factor is mycolactone, a lipid cytotoxic molecule. Buruli ulcer has high morbidity, particularly in rural West Africa where the disease is endemic. Data have shown that infected lesions of Buruli ulcer patients can be colonized by quorum sensing bacteria such as Staphylococcus aureus, S.

CRISPR-Cas9 modified bacteriophage for treatment of Staphylococcus aureus induced osteomyelitis and soft tissue infection.

Osteomyelitis, or bone infection, is often induced by antibiotic resistant Staphylococcus aureus strains of bacteria. Although debridement and long-term administration of antibiotics are the gold standard for osteomyelitis treatment, the increase in prevalence of antibiotic resistant bacterial strains limits the ability of clinicians to effectively treat infection. Bacteriophages (phages), viruses that in a lytic state can effectively kill bacteria, have gained recent attention for their high specificity, abundance in nature, and minimal risk of host toxicity.

Glycerol Monolaurate Contributes to the Antimicrobial and Anti-inflammatory Activity of Human Milk.

Human milk has antimicrobial compounds and immunomodulatory activities. We investigated glycerol monolaurate (GML) in human milk versus bovine milk and infant formula for antimicrobial and anti-inflammatory activities. Human milk contained approximately 3000 µg/ml of GML, compared to 150 μg/ml in bovine milk and none in infant formula.

The Group B Streptococcal surface antigen I/II protein, BspC, interacts with host vimentin to promote adherence to brain endothelium and inflammation during the pathogenesis of meningitis.

Streptococcus agalactiae (Group B Streptococcus, GBS) normally colonizes healthy adults but can cause invasive disease, such as meningitis, in the newborn. To gain access to the central nervous system, GBS must interact with and penetrate brain or meningeal blood vessels; however, the exact mechanisms are still being elucidated. Here, we investigate the contribution of BspC, an antigen I/II family adhesin, to the pathogenesis of GBS meningitis.

Effect of a DNA-based immunostimulant on growth, performance, and expression of inflammatory and immune mediators in beef calves abruptly weaned and introduced to a complete ration.

The effect of a DNA immunostimulant on inflammatory and immune responses, performance, and health in calves following abrupt weaning and introduction to a concentrate diet was tested. Sixty-four single source Angus crossbred steers were weaned on day 1 and assigned to receive a DNA immunostimulant (TRT) or saline (CON) on days 0, 2, 4, and 6. On day 0, steers received clostridial and respiratory vaccines and anthelmintic; they were then transported 2 h, allocated to pens (n = 8 per pen), and introduced to total mixed ration.

Bovine Staphylococcus aureus Superantigens Stimulate the Entire T Cell Repertoire of Cattle.

Superantigens (SAgs) represent a diverse family of bacterial toxins that induce Vβ-specific T cell proliferation associated with an array of important diseases in humans and animals, including mastitis of dairy cows. However, an understanding of the diversity and distribution of SAg genes among bovine strains and their role in the pathogenesis of mastitis is lacking. Population genomic analysis of 195 bovine isolates representing 57 unique sequence types revealed that strains encode 2 to 13 distinct SAgs and that the majority of isolates contain 5 or more SAg genes.

Induction of Immunosuppressive CD8CD25FOXP3 Regulatory T Cells by Suboptimal Stimulation with Staphylococcal Enterotoxin C1.

Superantigens (SAgs) produced by at high concentrations induce proliferation of T cells bearing specific TCR Vβ sequences and massive cytokinemia that cause toxic shock syndrome. However, the biological relevance of SAgs produced at very low concentrations during asymptomatic colonization or chronic infections is not understood. In this study, we demonstrate that suboptimal stimulation of human PBMCs with a low concentration (1 ng/ml) of staphylococcal enterotoxin C1, at which half-maximal T cell proliferation was observed, induced CD8CD25 T cells expressing markers related to regulatory T cells (Tregs), such as IFN-γ, IL-10, TGF-β, FOXP3, CD28, CTLA4, TNFR2, CD45RO, and HLA-DR.

The Staphylococcus aureus superantigen SElX is a bifunctional toxin that inhibits neutrophil function.

Bacterial superantigens (SAgs) cause Vβ-dependent T-cell proliferation leading to immune dysregulation associated with the pathogenesis of life-threatening infections such as toxic shock syndrome, and necrotizing pneumonia. Previously, we demonstrated that staphylococcal enterotoxin-like toxin X (SElX) from Staphylococcus aureus is a classical superantigen that exhibits T-cell activation in a Vβ-specific manner, and contributes to the pathogenesis of necrotizing pneumonia. Here, we discovered that SElX can also bind to neutrophils from human and other mammalian species and disrupt IgG-mediated phagocytosis.

Genetic engineering of a temperate phage-based delivery system for CRISPR/Cas9 antimicrobials against Staphylococcus aureus.

Discovery of clustered, regularly interspaced, short palindromic repeats and the Cas9 RNA-guided nuclease (CRISPR/Cas9) system provides a new opportunity to create programmable gene-specific antimicrobials that are far less likely to drive resistance than conventional antibiotics. However, the practical therapeutic use of CRISPR/Cas9 is still questionable due to current shortcomings in phage-based delivery systems such as inefficient delivery, narrow host range, and potential transfer of virulence genes by generalized transduction. In this study, we demonstrate genetic engineering strategies to overcome these shortcomings by integrating CRISPR/Cas9 system into a temperate phage genome, removing major virulence genes from the host chromosome, and expanding host specificity of the phage by complementing tail fiber protein.

Genotypic and Phenotypic Characterization of Methicillin-Resistant Staphylococcus aureus Isolated from Bovine Mastitic Milk in Korea.

Staphylococcus aureus is a major etiological pathogen for bovine mastitis, foodborne illness, and various clinical infections. Methicillin-resistant S. aureus (MRSA) has been isolated from bovine mastitic milk, and the presence of MRSA in milk is a major public health concern.

Transposase-Mediated Excision, Conjugative Transfer, and Diversity of ICE Elements in Staphylococcus aureus.

ICE represents one of two families of integrative conjugative elements (ICEs) identified in the pan-genome of the human and animal pathogen Here we investigated the excision and conjugation functions of ICE and further characterized the diversity of this element. ICE excision was not significantly affected by growth, temperature, pH, or UV exposure and did not depend on The IS-like DDE transposase (Tpase; encoded by and ) of ICE must be uninterrupted for excision to occur, whereas disrupting three of the other open reading frames (ORFs) on the element significantly affects the level of excision. We demonstrate that ICE conjugatively transfers to different backgrounds at frequencies approaching that of the conjugative plasmid pGO1.

Cannabidiol (CBD) induces functional Tregs in response to low-level T cell activation.

Many effects of the non-psychoactive cannabinoid, cannabidiol (CBD), have been described in immune responses induced by strong immunological stimuli. It has also been shown that CBD enhances IL-2 production in response to low-level T cell stimulation. Since IL-2, in combination with TGF-β1, are critical for Treg induction, we hypothesized that CBD would induce CD4CD25FOXP3 Tregs in response to low-level stimulation.

Genotype and enterotoxigenicity of Staphylococcus epidermidis isolate from ready to eat meat products.

We have previously shown that potentially pathogenic isolates of Staphylococcus epidermidis occur at high incidence in ready-to-eat food. Now, within 164 samples of ready-to-eat meat products we identified 32 S. epidermidis isolates.