BACKGROUND An accurate and prompt diagnosis of bacterial arthritis is essential for earlier treatment and a good outcome. Superantigens produced by Staph. Aureus are among the most lethal toxins. The paper objective was Identification of common bacterial antigens and S.aureus superantigens in synovial fluid (SF) of children with negative culture and direct smear for other bacteria except for S....

Three variants of the chloramine-T radioiodination method were used to iodinate staphylococcal enterotoxin A with 125I. Only one method consistently produced usable labels for radioimmunoassay. The iodine incorporation was 55 to 76%; the specific activity was 3.5 to 5.5 muCi/microgram of enterotoxin, and the label was extremely stable on storage at -20 degrees C. Determinations of the enterotox...

BACKGROUND In the previous studies using the commercial ELISA kit, the existence of staphylococcal superantigens has been reported in synovial fluid of patients with rheumatoid arthritis (RA). OBJECTIVES This study aimed to design molecular methods to detect staphylococcal enterotoxin C in synovial fluid of patients with rheumatoid arthritis. MATERIALS AND METHODS In this experimental study...

The superantigen staphylococcal enterotoxin A (SEA) binds to major histocompatibility complex (MHC) class II molecules at two sites on either side of the peptide groove. Two separate but cooperative interactions to the human class II molecule HLA-DR1 were detected. The first high affinity interaction to the DR1 beta chain is mediated by a zinc atom coordinated by H187, H225, and D227 in SEA and...

In this study, we investigated the interaction between apple polyphenols (AP; mainly consisting of procyanidin (PC) from an apple) and staphylococcal enterotoxin A (SEA), and the inhibitory effects of AP on SEA activity. According to the degree of polymerization, in particularly highly polymerized PC (more than pentamer) strongly interacted with SEA. The binding affinity of AP with SEA molecule...

The regulation of staphylococcal enterotoxin A (SEA) synthesis in a defined medium was studied using continuous culture techniques. SEA production was repressed by glucose and repression could be overcome by addition of exogenous cyclic AMP. As well as this classical catabolite repression control, addition of glucose to de-repressed steady-state cultures resulted in rapid disappearance of toxin...

OBJECTIVE The aim of this study was to construct a conditionally replicating adenovirus pPE3-SEA expressing staphylococcal enterotoxin A (SEA) gene. MATERIALS AND METHODS A full-length SEA gene fragment was cloned into pENTR12 plasmid to obtain a recombinant viral plasmid pENTR12-SEA. The pENTR12-SEA plasmid was co-transfected into HEK293 cells along with pPE3-ccdB, which encoded for the viru...

The electrophoretic mobility of enterotoxin B was investigated through the use of the disc electrophoresis technique. Ideal patterns were developed with a 7.5% acrylamide gel system (pH 4.3). The toxin can be separated and identified from other complex proteins such as serum or suspect samples of foods by this technique. The technique can be used as an assay method for the toxin as well as to e...

To seek information on the role of Fas in negative selection, we examined subsets of thymocytes from normal neonatal mice versus Fas-deficient lpr/lpr mice injected with graded doses of antigen. In normal mice, injection of 1-100 microg of staphylococcal enterotoxin B (SEB) induced clonal elimination of SEB-reactive Vbeta8+ cells at the level of the semi-mature population of HSAhi CD4+ 8- cells...