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Biomedical subjects

R N Robbins

Publications and source records attributed to R N Robbins.

14 recordsLinked to original sources
PubMed1987

Production of toxic shock syndrome toxin 1 by Staphylococcus aureus as determined by tampon disk-membrane-agar method.

The influence of 17 commercially available tampons on production of toxic shock syndrome toxin 1 (TSST-1) by Staphylococcus aureus was investigated by using a tampon disk method. Filter membranes overlaying agar medium (with or without blood) in small petri dishes were spread inoculated with a TSST-1-producing strain of S. aureus. Disks cut from unrolled tampons were pressed and laid on the inoculated membranes; incubation was for 19 h at 37 degrees C with 5% CO2 in air. CFU on the membranes and in the disks were enumerated, and the presence of TSST-1 in the disks and in the agar layers was determined. Tampons made of different materials supported characteristic levels of cell growth and toxin production in the tampon. Colonization of the interface surface of the tampon disks was heavy. The number of CFU extracted from the tampon disks ranged from 5 X 10(10) to 82 X 10(10). There was little variation in the CFU recovered from the membranes ([1.9 +/- 0.4] X 10(11)). Sixty to 170 micrograms of TSST-1 was recoverable from the agar, with an additional 10 to 90 micrograms recoverable from tampon disks, depending on the type of tampon disk. The amount of toxin in the agar layer from the various tampon disks was relatively constant and indicated an important contribution of toxin from vaginal S. aureus cells not growing in the tampon. The main role of tampons in toxic shock syndrome may be that of providing a fibrous surface for heavy colonization and sufficient air for TSST-1 production.

Bacterial Toxins↗
PubMed1985

Toxic shock syndrome--the role of the toxin.

From isolates of Staphylococcus aureus derived from patients suffering from toxic shock syndrome a toxin was identified by tests in monkeys and was found to be distinct from the enterotoxin responsible for staphylococcal food poisoning. When purified, this TSS toxin (TSST-1) was characterised and used to generate antibodies in rabbits. Only a small proportion of routine staphylococcal isolates produce TSST-1, though it is clear that this toxin has existed for some years. At the same time, TSST-1 producing staphylococci have been isolated in every continent, yet very few cases of toxic shock syndrome have been recognised in developing countries. Using the purified TSST-1, human sera have been examined for the presence of antibodies. Patients with the disease had either no antibodies, or low titres.

Animals↗
PubMed1984

Identification, purification, and some physicochemical properties of staphylococcal enterotoxin C3.

A third staphylococcal enterotoxin C (C3) has been identified, purified, and characterized. Staphylococcal enterotoxin C3 was identified from a Staphylococcus aureus isolated received from England. The purified toxin was determined by gel permeation chromatography and sodium dodecyl sulfate-polyacrylamide gel electrophoresis to be a simple protein with a molecular weight of 26,900. The isoelectric point of the major band was determined by isoelectric focusing in polyacrylamide gels to be 8.15. The reaction of enterotoxin C3 with its specific antibody was not affected by tryptic digestion at pH 8.0 or peptic digestion at pH 4.5. The enterotoxin C3 consisted of 236 amino acid residues. Serine was shown to be the NH2-terminal amino acid residue by end group analysis. The protein was highly emetic in cynomolgus monkeys both per os and intravenously.

Amino Acids↗
PubMed1983

Purification and some physicochemical properties of toxic-shock toxin.

A procedure for the purification of a protein marker for the staphylococci isolated from toxic-shock syndrome patients has been developed. The purification procedure involves the removal of the toxic protein from culture supernatant fluids of toxic-shock syndrome associated Staphylococcus aureus strains FRI-1169 and FRI-1183 by batch absorption with CG-50 resin, ion-exchange chromatography on CM-Sepharose CL-6B, and gel permeation chromatography on Sephacryl S-200. The purified toxin is a simple protein with a molecular weight of 24 000 +/- 500 as determined by sodium dodecyl sulfate-polyacrylamide gel electrophoresis. The isoelectric point of the major band is 7.0 as determined by isoelectric focusing in polyacrylamide gels. The TS-toxin's reactivity with its specific antibody is not affected by tryptic digestion at pH 8.0 but is slowly reduced by treatment with pepsin at pH 4.5. The TS-toxin consists of 188 amino acid residues. Serine was shown to be the NH2-terminal amino acid residue by end-group analysis. Initial studies indicated the protein was emetic; thus tentatively it was called staphylococcal enterotoxin F. In this paper it is called TS-toxin because the emetic action in monkeys has not been confirmed.

Amino Acids↗
PubMed1982

An enterotoxin-like protein in Staphylococcus aureus strains from patients with toxic shock syndrome.

An enterotoxin-like protein, tentatively labeled enterotoxin F, was isolated from Staphylococcus aureus strains taken from patients with toxic shock syndrome. Antibodies specific for enterotoxin F were prepared in rabbits. Use of these antibodies showed that 130 (91.5%) of 142 S. aureus strains from patients with toxic shock syndrome produced enterotoxin F. Strains from toxic shock patients in eight other countries were identified as enterotoxin F producers. Only a small number of S. aureus strains from sources other than patients with toxic shock syndrome were found to produce enterotoxin F. Twenty-one of 111 controls had low antibody titers (less than 1:100) to enterotoxin F whereas 86 of 92 toxic shock patients had low acute phase antibody titers (less than 1:100) to enterotoxin F. Eight of 52 patients had serum conversion as shown by an increase in antibody titer to enterotoxin F in sera taken 21 to 60 days after onset of the illness. It may be possible to identify persons susceptible to toxic shock syndrome by measuring their antibody titer to enterotoxin F.

Bacterial Toxins↗
PubMed1981

A new staphylococcal enterotoxin, enterotoxin F, associated with toxic-shock-syndrome Staphylococcus aureus isolates.

612 (93.8%) of 65 Staphylococcus aureus strains isolated from 65 patients with toxic-shock syndrome (TSS) produced an enterotoxin-like protein, tentatively identified as staphylococcal enterotoxin F (SEF). One of the other strains produced staphylococcal enterotoxin B and another exterotoxin C. In two blind studies all 34 TSS-associated S. aureau strains examined and 3 (11.5%) of 26 control S. aureau strains produced SEF. 2 of the latter strains were isolated from the vaginas of women who had no history of TSS. SEF was purified, and specific antibodies to it were prepared. Only 4 (4.6%) of 87 S. aureau strains from other sources were found to produce SEF. 5 (17.2%) of 29 TSS patients whose acute sera were available had anti-SEF antibody present in titres of greater than or equal to 1:100 as determined by radioimmunoassay, compared with 44 (78.6%) of 56 controls--demonstrating a greater serosusceptibility of TSS patients to SEF. It is suggested that staphylococcal enterotoxin, particularly SEF, may be a cause of the signs and symptoms of TSS.

Antibodies↗
PubMed1980

Isolation of specific and common antibodies to staphylococcal enterotoxins B, C1, and C2.

Staphylococcal enterotoxins C1 and C2 elicit the production of antibodies in rabbits that give precipitin reactions with both toxins and gel diffusion plates. These enterotoxins also elicit the production of antibodies that are specific for each of the enterotoxins. Enterotoxin B elicits the production of antibodies in some rabbits that react with enterotoxins B, C1, and C2 in gel diffusion plates and in radioimmunoassay. Antibodies specific for enterotoxin B are produced also. Enterotoxin C1 elicits the production of antibodies that cross-react weakly with enterotoxin B, indicating that the antigenic sites involved in the cross-reactions are not identical in the two toxins. The antibodies have been isolated by affinity chromatography.

Animals↗
PubMed1980

Antibodies to staphylococcal enterotoxin in laboratory personnel.

Eighty-five percent of laboratory personnel working with staphylococcal enterotoxin had antibodies to enterotoxin in their sera, whereas only 23% of the control group had antibodies specific for enterotoxin. Two persons who carried enterotoxin B-producing staphylococci in their noses, throats, or both, had antibodies to enterotoxin B in their sera.

Antibodies, Bacterial↗
PubMed1978

Isolation of specific and common antibodies to staphylococcal enterotoxins A and E by affinity chromatography.

Specific and common antibodies to staphylococcal enterotoxins A and E (SEA and SEE) were isolated from anti-SEA and anti-SEE antisera by affinity chromatography. Anti-SEA and anti-SEE antisera were passed through a column with the cross-reacting enterotoxin coupled to a CNBr-activated Sepharose 4B matrix. Specifically bound common antibodies were eluted with NaSCN. The isolated specific antibodies reacted only with the homologous enterotoxin, whereas the common antibodies gave a reaction of identify with both enterotoxins in double gel diffusion plates. The common antibodies had a higher titer against SEE than against SEA. The significance of the isolation of antibodies common to two separate protein molecules is discussed.

Animals↗
PubMed1971

Identification of enterotoxin E.

Identification of a new enterotoxin was accomplished by purification of the enterotoxin produced by staphylococcal strain FRI-326 and by preparation of specific antitoxin to the enterotoxin. Toxicity of the preparations was determined in rhesus monkeys, and specificity of the enterotoxin-antitoxin reaction was determined in gel diffusion plates. The enterotoxin was designated enterotoxin E.

Animals↗
PubMed1970

Relationship between staphylococcal antiserum titer and zone development on immune serum plates.

A workable relationship was established between the standard serum titers of staphylococcal immune antisera and the development of precipitin zones on serum agar around colonies of staphylococcal strains producing homologous antigens (enterotoxins). The standard titer of a serum is defined as the reciprocal of that serum dilution which, with 10 mug of pure enterotoxin per ml, will give a precipitin zone 10 mm in length in single gel-diffusion tubes after 7 days of incubation at 25 C. A numerical scale was set up for determining the intensity of precipitin zones on serum agar. A reading of 3 was considered optimum. This correlated well with a standard serum titer of 25, when 1 ml of such a serum was used per 20 ml of medium per serum plate. From this relationship, the minimum volume of serum required to give optimum precipitin zone development can be calculated.

Agar↗
PubMedDate not supplied

Effect of tampon wraps on production of toxic shock syndrome toxin 1.

The influence of tampon wraps on the production and distribution of toxic shock syndrome toxin 1 (TSST-1) was investigated with use of a disk-membrane-agar method. Filter membranes (45 micron) overlaying agar medium in 50-mm petri dishes were spread-inoculated with a TSST-1-producing strain of Staphylococcus aureus and covered with 0.5 mL of whole citrated rabbit blood. Disks of tampon core materials with and without wraps were placed on the inoculated membranes and incubated at 37 degrees C in 5% CO2 in air. Eight wraps with each of 14 tampon core materials were tested to determine the amount of toxin in the agar layer, a quantity considered an indicator of the relative amounts of toxin available for absorption in vivo. The average level of toxin in the agar layer with any particular wrap compared with that in the agar layer with no wrap was higher with five wraps, lower with two wraps, and essentially the same with one wrap. The lower levels of toxin were obtained with one wrap that had a starch binder and with one that contained the surfactant Standamul 1414-E. Standamul 1414-E has been reported to be an inhibitor of growth of and production of TSST-1 by S. aureus.

Bacterial Toxins↗