In vivo Suppression and Enhancement of the Murine Homocytotropic Antibody Response by Staphylococcal Enterotoxin A

1980 ◽  
Vol 63 (4) ◽  
pp. 470-472 ◽  
Author(s):  
S.E. Chen ◽  
C.S. Tse ◽  
I.L. Bernstein ◽  
D. Archer
Keyword(s):  
Antibody Response ◽  
Staphylococcal Enterotoxin ◽  
Staphylococcal Enterotoxin A

scholarly journals Effect of (−)-Epigallocatechin Gallate to Staphylococcal Enterotoxin A on Toxin Activity

Molecules ◽  
2020 ◽  
Vol 25 (8) ◽  
pp. 1867
Author(s):  
Yuko Shimamura ◽  
Mio Utsumi ◽  
Chikako Hirai ◽  
Ami Kurokawa ◽  
Toshiyuki Kan ◽  
...  
Keyword(s):  
Cell Proliferation ◽  
Epigallocatechin Gallate ◽  
Direct Interaction ◽  
Model Solution ◽  
Staphylococcal Enterotoxin ◽  
Hydroxyl Group ◽  
Staphylococcal Enterotoxin A ◽  
Toxic Activity ◽  
Alkaline Conditions

Staphylococcal enterotoxin A (SEA) functions both as superantigens that stimulate non-specific T cell proliferation as well as potent gastrointestinal toxins. We previously reported that (−)-epigallocatechin gallate (EGCG) binds to SEA. Therefore, the ability of EGCG to inhibit SEA toxin activity was examined. As a result, EGCG significantly decreased SEA-induced expression and production of interferon gamma (IFN-γ). In addition, EGCG inhibited SEA-induced spleen cell proliferation. To investigate the role of the galloyl group in EGCG on SEA cytotoxicity in more detail, the effect of the binding of a hydroxyl group at position 3 of the galloyl group in EGCG to SEA on SEA cytotoxicity was examined using two methylated EGCG. SEA cytotoxicity was significantly controlled in both (−)-3′′-Me-EGCG and (−)-4′′-Me-EGCG. These results suggest that EGCG inhibits toxic activity via direct interaction with SEA or without any interaction with SEA. The binding affinity between SEA and EGCG under in vivo conditions was examined using a model solution. Although after treatment under acidic and alkaline conditions, the presence of protein and the digestive tract model solution, EGCG still interacted with SEA. Our studies are the first to demonstrate the effect of the binding of EGCG to SEA on toxin activity.

Immunofluorescence Assay Using Monoclonal and Polyclonal Antibodies for Detection of Staphylococcal Enterotoxins A in Milk

2019 ◽  
Vol 13 (1) ◽  
pp. 137-145 ◽  
Author(s):  
Tzonka Godjevargova ◽  
Zlatina Becheva ◽  
Yavor Ivanov ◽  
Andrey Tchorbanov
Keyword(s):  
Monoclonal Antibody ◽  
Magnetic Nanoparticles ◽  
Polyclonal Antibody ◽  
Polyclonal Antibodies ◽  
Food Poisoning ◽  
Staphylococcal Enterotoxin ◽  
Staphylococcal Enterotoxin A ◽  
Fluorescence Immunoassay ◽  
Magnetic Separator ◽  
Milk Samples

Objectives: Staphylococcus aureus is a Gram-positive microorganism. S. aureus can grow in various foods and cause food poisoning by secreting enterotoxins. The most common enterotoxins involved in food poisoning are staphylococcal enterotoxin A and staphylococcal enterotoxin B, but Staphylococcal Enterotoxin A (SEA) is predominant. The main types of food contaminated with SEs are meat and meat products, poultry and eggs, milk and dairy products. The aim of this study was to develop a rapid and sensitive fluorescence immunoassay for detection of staphylococcal enterotoxin A in milk. Methods: Monoclonal and polyclonal antibodies for SEA were produced and characterized. Competitive fluorescence immunoassay based on Magnetic Nanoparticles (MNPs) was performed and optimized. MNPs were used as a solid carrier of the antibodies. The first step of the assay was immunoreaction between the immobilized antibody onto MNPs and SEA in milk sample. Then the fluorescein-SEA conjugate was added to the sample. Thus, competitive immunoreaction between MNP-mAb/MNP-pAb with SEA and SEA-FITC was performed. These immuno-complexes were separated by a magnetic separator and the obtained supernatants were analyzed. The fluorescent signal from the excess of conjugated SEA was proportional to the SEA contained in the milk. The assay duration was only 30 min. Results: The fluorescence immunoassays performed with polyclonal antibody had linear ranges from 5 pg/mL to 100 ng/mL SEA in a buffer, and from 50 pg/mL to 50 ng/mL SEA in spiked milk samples. While the same assays performed with monoclonal antibody had linear ranges from 1 pg/mL to 20 ng/mL SEA in buffer, and from 10 pg/mL to 10 ng/mL SEA in spiked milk samples. The detection limits of the developed immunoassays performed in milk were: 48 pg/mL with polyclonal antibody and 9 pg/mL with monoclonal antibody. Conclusion: A rapid and sensitive fluorescence immunoassay based on magnetic nanoparticles with a polyclonal and monoclonal antibody for determination of staphylococcal enterotoxin A in milk was developed.

The in vivo antibody response in rat gut-associated lymphoid tissue (GALT) after immunization with bacterial polysaccharide antigen

1993 ◽  
Vol 144 (2) ◽  
pp. 121-128 ◽  
Author(s):  
M. Soesatyo ◽  
G.P.J.M. Van den Dobbelsteen ◽  
E.P. Van Rees ◽  
J. Biewenga ◽  
T. Sminia
Keyword(s):  
Antibody Response ◽  
Lymphoid Tissue ◽  
Bacterial Polysaccharide ◽  
Polysaccharide Antigen ◽  
Rat Gut

scholarly journals Mass Outbreak of Food Poisoning Disease Caused by Small Amounts of Staphylococcal Enterotoxins A and H

2005 ◽  
Vol 71 (5) ◽  
pp. 2793-2795 ◽  
Author(s):  
Tetsuya Ikeda ◽  
Naoto Tamate ◽  
Keiji Yamaguchi ◽  
Sou-ichi Makino
Keyword(s):  
Food Poisoning ◽  
Staphylococcal Enterotoxin ◽  
Raw Material ◽  
Staphylococcal Enterotoxin A ◽  
Staphylococcal Enterotoxins ◽  
Reconstituted Milk

ABSTRACT It was believed that food poisoning in Osaka in 2000 was due to small amounts of staphylococcal enterotoxin A (SEA) in reconstituted milk. Results of this study clearly indicate that SEH was also present in the raw material of reconstituted milk, indicating that the food poisoning was caused by multiple staphylococcal enterotoxins.

scholarly journals Heavily Isotype-Dependent Protective Activities of Human Antibodies against Vaccinia Virus Extracellular Virion Antigen B5

2009 ◽  
Vol 83 (23) ◽  
pp. 12355-12367 ◽  
Author(s):  
Mohammed Rafii-El-Idrissi Benhnia ◽  
Megan M. McCausland ◽  
John Laudenslager ◽  
Steven W. Granger ◽  
Sandra Rickert ◽  
...  
Keyword(s):  
Antibody Response ◽  
Vaccinia Virus ◽  
Smallpox Vaccine ◽  
Human Antibody ◽  
Human Mabs ◽  
Complement Components ◽  
Vaccinia Virion ◽  
Virion Antigen

ABSTRACT Antibodies against the extracellular virion (EV or EEV) form of vaccinia virus are an important component of protective immunity in animal models and likely contribute to the protection of immunized humans against poxviruses. Using fully human monoclonal antibodies (MAbs), we now have shown that the protective attributes of the human anti-B5 antibody response to the smallpox vaccine (vaccinia virus) are heavily dependent on effector functions. By switching Fc domains of a single MAb, we have definitively shown that neutralization in vitro—and protection in vivo in a mouse model—by the human anti-B5 immunoglobulin G MAbs is isotype dependent, thereby demonstrating that efficient protection by these antibodies is not simply dependent on binding an appropriate vaccinia virion antigen with high affinity but in fact requires antibody effector function. The complement components C3 and C1q, but not C5, were required for neutralization. We also have demonstrated that human MAbs against B5 can potently direct complement-dependent cytotoxicity of vaccinia virus-infected cells. Each of these results was then extended to the polyclonal human antibody response to the smallpox vaccine. A model is proposed to explain the mechanism of EV neutralization. Altogether these findings enhance our understanding of the central protective activities of smallpox vaccine-elicited antibodies in immunized humans.

scholarly journals Production of Staphylococcal Enterotoxin A in Blue, Brick, Mozzarella, and Swiss Cheeses

1973 ◽  
Vol 56 (4) ◽  
pp. 429-435 ◽  
Author(s):  
S.R. Tatini ◽  
W.D. Wesala ◽  
J.J. Jezeski ◽  
H.A. Morris
Keyword(s):  
Staphylococcal Enterotoxin ◽  
Staphylococcal Enterotoxin A
Sign in / Sign up

Export Citation Format

Share Document