Evaluation of the Efficacy of a Cholera Toxin-Based Staphylococcus aureus Vaccine against Bovine Intramammary Challenge

Staphylococcus aureus (S. aureus) is a primary agent of bovine mastitis and a source of significant economic loss for the dairy industry. We previously reported antigen-specific immune induction in the milk and serum of dairy cows following vaccination with a cholera toxin A2 and B subunit (CTA2/B) based vaccine containing the iron-regulated surface determinant A (IsdA) and clumping factor A (ClfA) antigens of S. aureus (IsdA + ClfA-CTA2/B). The goal of the current study was to assess the efficacy of this vaccine to protect against S. aureus infection after intramammary challenge. Six mid-lactation heifers were randomized to vaccinated and control groups. On days 1 and 14 animals were inoculated intranasally with vaccine or vehicle control, and on day 20 animals were challenged with S. aureus. Clinical outcome, milk quality, bacterial shedding, and somatic cell count (SCC) were followed for ten days post-challenge. Vaccinated animals did not show signs of clinical S. aureus mastitis and had lower SCCs compared to control animals during the challenge period. Reductions in bacterial shedding were observed but were not significant between groups. Antibody analysis of milk and serum indicated that, upon challenge, vaccinated animals produced enhanced IsdA- and ClfA-CTA2/B specific immunoglobulin G (IgG) responses, while responses to CTA2/B alone were not different between groups. Responses after challenge were largely IgG1 against the IsdA antigen and mixed IgG1/IgG2 against the ClfA antigen. In addition, there was a significant increase in interferon gamma (IFN-γ) expression from blood cells in vaccinated animals on day 20. While preliminary, these findings support evidence of the induction of active immunity by IsdA + ClfA-CTA2/B, and further assessment of this vaccine is warranted.

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Differential Biological and Adjuvant Activities of Cholera Toxin and Escherichia coli Heat-Labile Enterotoxin Hybrids

Infection and Immunity ◽

10.1128/iai.69.3.1528-1535.2001 ◽

2001 ◽

Vol 69 (3) ◽

pp. 1528-1535 ◽

Cited By ~ 40

Author(s):

Christal C. Bowman ◽

John D. Clements

Keyword(s):

Escherichia Coli ◽

Cyclic Amp ◽

Cholera Toxin ◽

The Other ◽

Toxin Gene ◽

Wild Type ◽

B Subunit ◽

Heat Labile ◽

A Subunit ◽

Ifn Γ

ABSTRACT Two bacterial products that have been demonstrated to function as mucosal adjuvants are cholera toxin (CT), produced by various strains of Vibrio cholerae, and the heat-labile enterotoxin (LT) produced by some enterotoxigenic strains of Escherichia coli. Although LT and CT have many features in common, they are clearly distinct molecules with biochemical and immunologic differences which make them unique. The goal of this study was to determine the basis for these biological differences by constructing and characterizing chimeric CT-LT molecules. Toxin gene fragments were subcloned to create two constructs, each expressing the enzymatically active A subunit of one toxin and the receptor binding B subunit of the other toxin. These hybrid toxins were purified, and the composition and assembly of CT A subunit (CT-A)-LT B subunit (LT-B) and LT A subunit (LT-A)-CT B subunit (CT-B) were confirmed. Hybrids were evaluated for enzymatic activity, as measured by the accumulation of cyclic AMP in Caco-2 cells, and the enterotoxicity of each toxin was assessed in a patent-mouse assay. The results demonstrated that LT-A–CT-B induces the accumulation of lower levels of cyclic AMP and has less enterotoxicity than either wild-type toxin or the other hybrid. Nonetheless, this hybrid retains adjuvant activity equivalent to or greater than that of either wild-type toxin or the other hybrid when used in conjunction with tetanus toxoid for intranasal immunization of BALB/c mice. Importantly, the ability of LT to induce a type 1 cytokine response was found to be a function of LT-A. Specifically, LT-A–CT-B was able to augment the levels of antigen-specific gamma interferon (IFN-γ) and interleukin 5 to levels comparable to those achieved with native LT, while CT-A–LT-B and native CT both produced lower levels of antigen-specific IFN-γ. Thus, these toxin hybrids possess unique biological characteristics and provide information about the basis for differences in the biological activities observed for CT and LT.

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Roles of Mannosylerythritol Lipid-B Components In Antimicrobial Activity Against Bovine Mastitis-Causing Staphylococcus Aureus

10.21203/rs.3.rs-561655/v1 ◽

2021 ◽

Author(s):

Shinya Yamauchi ◽

Mutsumi Furukawa ◽

Akio Kawahara ◽

Tomohiro Sugahara ◽

Shuhei Yamamoto ◽

...

Keyword(s):

Fatty Acids ◽

Staphylococcus Aureus ◽

Antimicrobial Activity ◽

Mechanism Of Action ◽

Bovine Mastitis ◽

Economic Loss ◽

Mannosylerythritol Lipid ◽

Gram Positive ◽

Bacterial Surface ◽

High Concentrations

Abstract Mannosylerythritol lipid-B (MEL-B), which comprises ester-bonded hydrophilic ME and hydrophobic fatty acids, is a bio-surfactant with various unique properties, including antimicrobial activity against most gram-positive bacteria. The gram-positive Staphylococcus aureus is a causative pathogen of dairy cattle mastitis, which results in considerable economic loss in dairy industry. Here, we demonstrate the efficacy of MEL-B as a disinfectant against bovine-derived S. aureus and elucidate a mechanism of action of MEL-B in inhibition of bacterial growth. The growth of bovine mastitis causative S. aureus BM1006 was inhibited when cultured with MEL-B above 10 ppm (equivalent to 0.015 mM). The activity of MEL-B required fatty acids (i.e., caprylic and myristoleic acids) as ME, the component of MEL-B lacking fatty acids, did not inhibit the growth of S. aureus even at high concentrations. Importantly, ME-bound fatty acids effectively inhibited the growth of S. aureus when compared with free fatty acids. Specifically, the concentrations of ME-bound fatty acids and free caprylic and myristoleic acids required to inhibit the growth of S. aureus were 0.015, 10, and 1 mM, respectively. The involvement of ME in the antimicrobial activity of MEL-B was confirmed by digestion of MEL-B with lipase, which dissociated ME and fatty acids. These results indicated that a mechanism of action of MEL-B in inhibiting the growth of S. aureus could be explained by the effective transporting of antimicrobial fatty acids to the bacterial surface via hydrophilic ME.

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Development of a Cholera Toxin CTA2/B Based Staphylococcus aureus Vaccine to Prevent Bovine Mastitis

10.18122/b26q7c ◽

2017 ◽

Author(s):

Neha Misra

Keyword(s):

Staphylococcus Aureus ◽

Cholera Toxin ◽

Bovine Mastitis

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Immunogenicity of a Staphylococcus aureus-cholera toxin A2/B vaccine for bovine mastitis

Vaccine ◽

10.1016/j.vaccine.2018.04.067 ◽

2018 ◽

Vol 36 (24) ◽

pp. 3513-3521 ◽

Cited By ~ 4

Author(s):

N. Misra ◽

T.F. Wines ◽

C.L. Knopp ◽

R. Hermann ◽

L. Bond ◽

...

Keyword(s):

Staphylococcus Aureus ◽

Cholera Toxin ◽

Bovine Mastitis

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The recombinant pseudorabies virus expressing porcine deltacoronavirus spike protein is safe and effective for mice

BMC Veterinary Research ◽

10.1186/s12917-021-03115-1 ◽

2022 ◽

Vol 18 (1) ◽

Author(s):

Yao Huang ◽

Zhiwen Xu ◽

Sirui Gu ◽

Mincai Nie ◽

Yuling Wang ◽

...

Keyword(s):

Antibody Level ◽

Recombinant Strain ◽

Gene Editing ◽

Pseudorabies Virus ◽

Virulent Strain ◽

Neutralizing Antibody ◽

Economic Loss ◽

Recombinant Pseudorabies Virus ◽

Ifn Γ ◽

Significant Economic Loss

Abstract Background Porcine deltacoronavirus (PDCoV) is a new pathogenic porcine intestinal coronavirus, which has appeared in many countries since 2012. PDCoV disease caused acute diarrhea, vomiting, dehydration and death in piglets, resulted in significant economic loss to the pig industry. However, there is no commercially available vaccine for PDCoV. In this study, we constructed recombinant pseudorabies virus (rPRVXJ-delgE/gI/TK-S) expressing PDCoV spike (S) protein and evaluated its safety and immunogenicity in mice. Results The recombinant strain rPRVXJ-delgE/gI/TK-S obtained by CRISPR/Cas gE gene editing technology and homologous recombination technology has genetic stability in baby hamster syrian kidney-21 (BHK-21) cells and is safe to mice. After immunizing mice with rPRVXJ-delgE/gI/TK-S, the expression levels of IFN-γ and IL-4 in peripheral blood of mice were up-regulated, the proliferation of spleen-specific T lymphocytes and the percentage of CD4+ and CD8+ lymphocytes in mice spleen was increased. rPRVXJ-delgE/gI/TK-S showed good immunogenicity for mice. On the seventh day after booster immunity, PRV gB and PDCoV S specific antibodies were detected in mice, and the antibody level continued to increase, and the neutralizing antibody level reached the maximum at 28 days post- immunization (dpi). The recombinant strain can protect mice with 100% from the challenge of virulent strain (PRV XJ) and accelerate the detoxification of PDCoV in mice. Conclusion The recombinant rPRVXJ-delgE/gI/TK-S strain is safe and effective with strong immunogenicity and is expected to be a candidate vaccine against PDCoV and PRV.

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Oral administration to NOD mice of diabetic autoantigens: Pure and linked to cholera toxin B subunit

Immunology Letters ◽

10.1016/s0165-2478(97)88813-x ◽

1997 ◽

Vol 56 (1-3) ◽

pp. 484

Author(s):

I Bache

Keyword(s):

Oral Administration ◽

Cholera Toxin ◽

Nod Mice ◽

Cholera Toxin B Subunit ◽

Toxin B ◽

Cholera Toxin B ◽

B Subunit

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Dendritic Cell-Mediated Induction of Mucosal Cytotoxic Responses following Intravaginal Immunization with the Nontoxic B Subunit of Cholera Toxin

The Journal of Immunology ◽

10.4049/jimmunol.176.5.2749 ◽

2006 ◽

Vol 176 (5) ◽

pp. 2749-2757 ◽

Cited By ~ 47

Author(s):

Carmelo Luci ◽

Catherine Hervouet ◽

Déborah Rousseau ◽

Jan Holmgren ◽

Cecil Czerkinsky ◽

...

Keyword(s):

Dendritic Cell ◽

Cholera Toxin ◽

B Subunit ◽

Cytotoxic Responses

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Molecular Characterization of Staphylococcus aureus Isolated from Bovine Mastitis and Close Human Contacts in South African Dairy Herds: Genetic Diversity and Inter-Species Host Transmission

Frontiers in Microbiology ◽

10.3389/fmicb.2017.00511 ◽

2017 ◽

Vol 8 ◽

Cited By ~ 34

Author(s):

Tracy Schmidt ◽

Marleen M. Kock ◽

Marthie M. Ehlers

Keyword(s):

Genetic Diversity ◽

Staphylococcus Aureus ◽

South African ◽

Molecular Characterization ◽

Bovine Mastitis ◽

Dairy Herds

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Impact of Nisin and Nisin-Producing Lactococcus lactis ssp. lactis on Clostridium tyrobutyricum and Bacterial Ecosystem of Cheese Matrices

Foods ◽

10.3390/foods10040898 ◽

2021 ◽

Vol 10 (4) ◽

pp. 898

Author(s):

Hebatoallah Hassan ◽

Daniel St-Gelais ◽

Ahmed Gomaa ◽

Ismail Fliss

Keyword(s):

Lactococcus Lactis ◽

Cheddar Cheese ◽

Economic Loss ◽

Gas Production ◽

Clostridium Tyrobutyricum ◽

Nisin Production ◽

Genus Clostridium ◽

Milk Pasteurization ◽

Cheese Slurry ◽

Significant Economic Loss

Clostridium tyrobutyricum spores survive milk pasteurization and cause late blowing of cheeses and significant economic loss. The effectiveness of nisin-producing Lactococcus lactis ssp. lactis 32 as a protective strain for control the C. tyrobutyricum growth in Cheddar cheese slurry was compared to that of encapsulated nisin-A. The encapsulated nisin was more effective, with 1.0 log10 reductions of viable spores after one week at 30 °C and 4 °C. Spores were not detected for three weeks at 4 °C in cheese slurry made with 1.3% salt, or during week 2 with 2% salt. Gas production was observed after one week at 30 °C only in the control slurry made with 1.3% salt. In slurry made with the protective strain, the reduction in C. tyrobutyricum count was 0.6 log10 in the second week at 4 °C with both salt concentration. At 4 °C, nisin production started in week 2 and reached 97 µg/g after four weeks. Metabarcoding analysis targeting the sequencing of 16S rRNA revealed that the genus Lactococcus dominated for four weeks at 4 °C. In cheese slurry made with 2% salt, the relative abundance of the genus Clostridium decreased significantly in the presence of nisin or the protective strain. The results indicated that both strategies are able to control the growth of Clostridium development in Cheddar cheese slurries.

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