Toxic shock syndrome toxin-1

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Immunoblots for detection of toxic shock syndrome toxin 1 produced by Staphylococcus aureus

Immunoblots for detection of toxic shock syndrome toxin 1 produced by Staphylococcus aureus

Colony immunoblot assay for the detection of staphylococcal toxic shock syndrome toxin 1 TSST-1 with anti-TSST-1 Fab'2 fragments.. Rapid screening assay for toxic shock syndrome toxin pr[r]

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Competitive, enzyme linked immunosorbent assay for toxic shock syndrome toxin 1

Competitive, enzyme linked immunosorbent assay for toxic shock syndrome toxin 1

We developed a competitive, enzyme-linked immunosorbent assay for the quantitation of toxic shock syndrome toxin 1 TSST-1.. Polyvalent immunoglobulin G from immunized rabbits was used as[r]

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Detection of New Methicillin Resistant Staphylococcus aureus Clones Containing the Toxic Shock Syndrome Toxin 1 Gene Responsible for Hospital  and Community Acquired Infections in France

Detection of New Methicillin Resistant Staphylococcus aureus Clones Containing the Toxic Shock Syndrome Toxin 1 Gene Responsible for Hospital and Community Acquired Infections in France

Methicillin-resistant Staphylococcus aureus (MRSA) clones harboring the toxic shock syndrome toxin 1 (tst) gene have been detected in France and in Switzerland since 2002. During a passive survey conducted between 2002 and 2003, we collected 103 tst-positive S. aureus isolates from 42 towns in France, of which 27 were resistant to methicillin. The tst-positive MRSA belonged to two clones: a major clone comprising 25 isolates of sequence type (ST) 5 and agr group 2 and a minor clone comprising two isolates of ST30 and agr3. The tst-positive MRSA clones were associated with both hospital-acquired (12 cases) and community-acquired (8 cases) infections. The MRSA clones were mainly isolated from children (overall median age, 3 years). They caused a variety of clinical syndromes, including toxic shock syndrome and suppurative infections. Both clones were found to harbor a type IV staphylococcal chromosomal cassette mec (SCCmec) and to have similar antibiotic resistance profiles (usually resistant to oxacillin, kanamycin, and tobramycin and with intermediate resistance to fusidic acid). The origin of these clones is unclear. The tst-positive agr2 MRSA clone has the same sequence type (ST5) of two pandemic nosocomial MRSA clones, namely, the Pediatric clone and the New York/Japan clone. These findings suggest that all these clones are phylogenetically related. The pulsotype of the tst-positive MRSA clones differed from that of methicillin-sensitive S. aureus (MSSA) clones by a single band involving the SCCmec element. These findings suggest that the tst-positive MRSA clones may have emerged from their respective MSSA counterparts.
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Influence of Subinhibitory Concentrations of Honey on Toxic Shock Syndrome Toxin  1 (TSST 1) Production by Two Strains of Staphylococcus Aureus

Influence of Subinhibitory Concentrations of Honey on Toxic Shock Syndrome Toxin 1 (TSST 1) Production by Two Strains of Staphylococcus Aureus

Staphylococcus aureus is a common pathogen associated with a large proportion of nosocomial and community acquired infections resulting in high morbidity and mortality. Diseases caused by this microbe include skin and soft tissue abscesses, toxic shock syndrome (TSS), scalded skin syndrome, food poisoning, pneumonia and septicaemia [1,2].Treatment of diseases caused by S. aureus is difficult because of the emergence of multi- antibiotic resistant strains, including methicillin resistant S. aureus (MRSA) and vancomycin resistant S. aureus (VRSA) [3,4,5]. The ability of S.aureus to cause disease is largely dependent on the presence of extracellular virulence factors, including surface and secreted toxins [2]. Some of the most important and well studied extracellular virulence factors include four distinct haemolysins (alpha, beta, gamma and delta), toxic shock syndrome toxin1 (TSST-1), staphylococcal enterotoxins
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Production and characterization of monoclonal antibodies to toxic shock syndrome toxin 1 and use of a monoclonal antibody in a rapid, one step enzyme linked immunosorbent assay for detection of picogram quantities of toxic shock syndrome toxin 1

Production and characterization of monoclonal antibodies to toxic shock syndrome toxin 1 and use of a monoclonal antibody in a rapid, one step enzyme linked immunosorbent assay for detection of picogram quantities of toxic shock syndrome toxin 1

Twenty-six hybridoma cell lines that produced monoclonal antibodies to toxic shock syndrome toxin 1 TSST-1 were generated by immunizing mice with a highly purified preparation of TSST-1 [r]

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Toxic Shock Syndrome Toxin 1 Evaluation and Antibiotic Impact in a Transgenic Model of Staphylococcal Soft Tissue Infection

Toxic Shock Syndrome Toxin 1 Evaluation and Antibiotic Impact in a Transgenic Model of Staphylococcal Soft Tissue Infection

IMPORTANCE Staphylococcal toxic shock syndrome (TSS) is a life-threatening illness causing fever, rash, and shock, attributed to toxins produced by the bacterium Staphylococcus aureus, mainly toxic shock syndrome toxin 1 (TSST-1). TSS was in the past commonly linked with menstruation and high-absorbency tampons; now, TSS is more frequently triggered by other staphylococcal infections, particularly of skin and soft tissue. Investigating the progress and treatment of TSS in patients is challeng- ing, as TSS is rare; animal models do not mimic TSS adequately, as toxins interact best with human immune cells. We developed a new model of staphylococcal soft tissue infection in mice producing human immune cell proteins, rendering them TSST-1 sensitive, to investigate TSS. The significance of our research was that TSST-1 was found in soft tissues and immune organs of mice and that early treatment of mice with the antibiotic clindamycin altered TSST-1 production. Therefore, the early treatment of patients suspected of having TSS with clindamycin may influence their response to treatment.
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Specific Inhibitory Action of Anisodamine against a Staphylococcal Superantigenic Toxin, Toxic Shock Syndrome Toxin 1 (TSST-1), Leading to Down-Regulation of Cytokine Production and Blocking of TSST-1 Toxicity in Mice

Specific Inhibitory Action of Anisodamine against a Staphylococcal Superantigenic Toxin, Toxic Shock Syndrome Toxin 1 (TSST-1), Leading to Down-Regulation of Cytokine Production and Blocking of TSST-1 Toxicity in Mice

Toxic shock syndrome toxin 1 (TSST-1), produced by Staphylococcus aureus (including methicillin-resistant S. aureus), is a superantigenic toxin responsible for toxic shock syndrome as well as neonatal TSS-like exanthematous disease. TSST-1 exhibits its deleterious effects by leading to the abnormal proliferation of, e.g., V ␤ 2 ⴙ T cells and overproduction of proinflammatory cytokines. In the present study we examined the inhibitory effect of a Chinese herbal extract, anisodamine, on TSST-1 using human peripheral blood mono- nuclear cells (PBMCs). Anisodamine inhibited the production of proinflammatory cytokines better than interleukin-10 (an anti-inflammatory cytokine). The inhibitory effect of anisodamine was greater than that of any tropane alkaloid examined. Anisodamine acted directly on both monocytes and T cells in human PBMCs, and the effect was confirmed at the transcriptional level. Inhibition of NF- ␬ B activation was also demonstrated. In contrast, no significant inhibition of V ␤ 2 ⴙ T-cell proliferation was observed. In mice injected with TSST-1, anisodamine treatment significantly decreased serum proinflammatory cytokine levels and prevented TSST- 1-induced death. These results suggest that anisodamine specifically acts against the production of cytokines (inflammatory cytokines in particular) and not against V ␤ 2 ⴙ T-cell proliferation and that anisodamine may have a beneficial effect on TSST-1-associated disease.
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Prevalence of Toxic Shock Syndrome Toxin 1 Producing Staphylococcus aureus and the Presence of Antibodies to This Superantigen in Menstruating Women

Prevalence of Toxic Shock Syndrome Toxin 1 Producing Staphylococcus aureus and the Presence of Antibodies to This Superantigen in Menstruating Women

Menstrual toxic shock syndrome (mTSS) is thought to be associated with colonization with toxic shock syndrome toxin 1 (TSST-1)-producing Staphylococcus aureus in women with insufficient antibody titers. mTSS has been associated with menstruation and tampon use, and although it is rare, the effects can be life threatening. It remains of interest because of the widespread use of tampons, reported to be about 70% of women in the United States, Canada, and much of Western Europe. This comprehensive study was designed to determine S. aureus colonization and TSST-1 serum antibody titers in 3,012 menstruating women in North America between the ages of 13 and 40, particularly among age and racial groups that could not be assessed reliably in previous small studies. One out of every four subjects was found to be colonized with S. aureus in at least one of three body sites (nose, vagina, or anus), with approximately 9% colonized vaginally. Eighty-five percent of subjects had antibody titers ( > 1:32) to TSST-1, and the vast majority (81%) of teenaged subjects (13 to 18 years) had already developed antibody titers. Among carriers of toxigenic S. aureus, a significantly lower percentage of black women than of white or Hispanic women were found to have antibody titers ( > 1:32) to TSST-1 (89% versus 98% and 100%). These findings demonstrate that the majority of teenagers have antibody titers ( > 1:32) to TSST-1 and are presumed to be protected from mTSS. These findings also suggest that black women may be more susceptible to mTSS than previously thought.
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Rapid and Specific Detection of Toxigenic Staphylococcus aureus: Use of Two Multiplex PCR Enzyme Immunoassays for  Amplification and Hybridization of Staphylococcal  Enterotoxin Genes, Exfoliative Toxin Genes,  and Toxic Shock Syndrome Toxin 1 Gene

Rapid and Specific Detection of Toxigenic Staphylococcus aureus: Use of Two Multiplex PCR Enzyme Immunoassays for Amplification and Hybridization of Staphylococcal Enterotoxin Genes, Exfoliative Toxin Genes, and Toxic Shock Syndrome Toxin 1 Gene

Two multiplex PCR enzyme immunoassays (PCR-EIAs) were developed for Staphylococcus aureus exotoxin gene screening as an alternative to the conventional biological assays, which depend on detectable amounts of toxins produced. One set of oligonucleotide primers and probes was designed to search for enterotoxin A to E genes (entA, entB, entC, entD, and entE), and the other one was designed to detect the staphylococcal exfoliative toxin genes (eta and etb) and the toxic shock syndrome toxin 1 gene (tst). Oligonucleotide primers were used as published previously, modified or newly developed to meet the requirements of both good size-distinguish- able amplification bands of multiplex PCR and the temperature limit of the uracil DNA glycosylase system for carryover protection. Amplification products were visualized by agarose gel electrophoresis, and specificity was controlled with the aid of a DNA EIA system using oligonucleotide probes derived from the sequences of the S. aureus toxin genes. PCR procedures were performed by using template nucleic acids extracted from a panel of S. aureus reference strains and from a collection of 50 clinical strains. The PCR results were compared with those of immunological toxin production assays. This multiplex PCR-EIA system offers an alternative method for the rapid, sensitive, specific, and simultaneous detection of the clinically important exotoxin potency of isolated S. aureus strains for diagnostic purposes as well as research studies.
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Dye labelled monoclonal antibody assay for detection of Toxic Shock Syndrome Toxin -1 from Staphylococcus aureus

Dye labelled monoclonal antibody assay for detection of Toxic Shock Syndrome Toxin -1 from Staphylococcus aureus

Assay of enterotoxins (A-D) and TSST-1. The supernatant fluids were tested for the presence of enterotoxins and TSST-1 using Reverse Passive Latex Agglutination (RPLA) test kits from Oxoid Unipath (TST-RPLA, TD 940A for TSST-1 and SET-RPLA, TD900A for enterotoxins) according to the manufacturers specifications. Briefly, phosphate buffered saline (PBS, 25 µl) containing 5% bovine serum albumin was dispensed in each well of two rows in a 96 well conical bottom microtitre plate. Supernatant fluid (25 µl) was added to the first and second well of each row and doubling dilutions were performed to give titres ranging from 1:2 to 1:256. 25 µl of latex suspension sensitised with specific antibodies against TSST-1 or enterotoxins was added to each well in the first row. Twenty-five microliters of control latex suspension sensitised with non- immune rabbit immunoglobulin was added to each well of the second row. After thorough mixing, the plates were incubated in a humidified box for 18- 20 h at room temperature. The titres were expressed as the reciprocal of the last dilution which gave an agglutination reaction (lattice). The control row showed a negative reaction (pellet) to indicate there was no non-specific reaction.
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Investigation by improved syringe method of effect of tampons on production in vitro of toxic shock syndrome toxin 1 by Staphylococcus aureus

Investigation by improved syringe method of effect of tampons on production in vitro of toxic shock syndrome toxin 1 by Staphylococcus aureus

Brand B, cardboard applicator Rayon Junior Rayon Slender Cotton Regular Rayon-cotton Super Rayon-modified cellulose Super Plus Brand B, plastic applicator.. Rayon-modified cellulose Supe[r]

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Prevalence of Toxic Shock Syndrome Toxin 1 (TSST 1) Producing Strains of Staphylococcus aureus and Antibody to TSST 1 among Healthy Japanese Women

Prevalence of Toxic Shock Syndrome Toxin 1 (TSST 1) Producing Strains of Staphylococcus aureus and Antibody to TSST 1 among Healthy Japanese Women

The relatively low rate of seropositivity for TSST-1 in Japan was not a result of lack of colonization by S. aureus and spe- cifically by TSST-1-producing strains: 52% of women were colonized with S. aureus at one or more mucosal sites (Table 2), 8.8% of all isolates produced TSST-1, and 6% of women were colonized with a TSST-1-producing strain. Two of the 209 women (0.9%) had TSST-1-producing S. aureus vaginal colo- nization, which is similar to the rate found in other geograph- ical locations (1, 4, 24, 36, 39). Colonization with a toxin- producing strain was associated with a high rate of antibody positivity: 92% of women colonized with a toxin-producing strain had a high level of antibody (Fig. 4). Subjects with nose and/or throat colonization with a toxin-producing strain had higher antibody titers than those with vaginal colonization (Ta- ble 3). It has been demonstrated that nasal exposure to supe- rantigens (e.g., TSST-1) is an excellent avenue for generating neutralizing antibodies to superantigens and for enhancing the bactericidal activity of neutrophils (30). Furthermore, the nasal mucosae consist of a thin, pseudostratified, columnar epithelium interspersed with glandular ducts and resting on a basement membrane. This nasal basement membrane is semipermeable due to capillary penetration, which makes it fundamentally dif- ferent from basement membranes found elsewhere in the hu- man body (54). One could speculate that the nasal basement membrane of the throat and nasal mucosal surfaces may be easier for toxin to penetrate than the more robust barrier of the vagina (7, 42). These differences may warrant further in- FIG. 4. Titers of anti-TSST-1 antibodies in Japanese women in Tokyo and Japanese women colonized with TSST-1-producing S. aureus.
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Detection of genes for enterotoxins, exfoliative toxins, and toxic shock syndrome toxin 1 in Staphylococcus aureus by the polymerase chain reaction

Detection of genes for enterotoxins, exfoliative toxins, and toxic shock syndrome toxin 1 in Staphylococcus aureus by the polymerase chain reaction

Eight pairs of synthetic oligonucleotide primers were used in a polymerase chain reaction PCR protocol to detect genes for staphylococcal enterotoxins A to E, exfoliative toxins A and B,[r]

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Oligonucleotide probes for detection and differentiation of Staphylococcus aureus strains containing genes for enterotoxins A, B, and C and toxic shock syndrome toxin 1

Oligonucleotide probes for detection and differentiation of Staphylococcus aureus strains containing genes for enterotoxins A, B, and C and toxic shock syndrome toxin 1

Different synthetic DNA nucleotide sequences were evaluated as gene probes for the specific detection and differentiation of Staphylococcus aureus strains encoding enterotoxins A SEA, B [r]

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Persistence survey of Toxic Shock Syndrome toxin 1 producing Staphylococcus aureusand serum antibodies to this superantigen in five groups of menstruating women

Persistence survey of Toxic Shock Syndrome toxin 1 producing Staphylococcus aureusand serum antibodies to this superantigen in five groups of menstruating women

Menstrual TSS is generally thought to be caused by S. aureus TSST-1 in a susceptible host [8,9]. TSST-1 is considered a superantigen (SAg), a class of very potent immune stimulators that interact with the immune sys- tem in a way that is different from conventional anti- gens. As a result, the magnitude of immune stimulation by a SAg is usually 10-500,000 fold higher than with convention antigens. This exaggerated release of inflam- matory cytokines is responsible for the clinical signs of illness associated with these toxins [10,11]. Individuals who lack neutralizing antibodies to a SAg are at a higher risk of developing severe systemic disease with hypotension and organ failure, particularly if they hap- pen to be high responders to these specific SAgs [11-13].
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Detection and quantitation of toxic shock syndrome toxin 1 in vitro and in vivo by noncompetitive enzyme linked immunosorbent assay

Detection and quantitation of toxic shock syndrome toxin 1 in vitro and in vivo by noncompetitive enzyme linked immunosorbent assay

Of 60 isolates negative for TSST-1 production as tested by immunodiffusion, 42 would be falsely positive by ELISA if culture supernatants were not pretreated with 10% normal rabbit serum[r]

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Oxygen and Carbon Dioxide Regulation of Toxic Shock Syndrome Toxin 1 Production by Staphylococcus aureus MN8

Oxygen and Carbon Dioxide Regulation of Toxic Shock Syndrome Toxin 1 Production by Staphylococcus aureus MN8

37°C while being continuously stirred with a Teflon-coated magnetic stir bar and were flushed at a rate of approximately 5 liters/min with a gas mixture (Praxair, St. Louis, Mo.). The gas mixtures contained a constant percentage of oxygen balanced with nitrogen and, when indicated, 7% carbon dioxide. The effect of stirring in the batch cultures was to entrain completely the atmosphere through- out the culture in the form of small bubbles, exposing the entire culture to atmospheric oxygen levels. In tests with an oxygen probe (model 5300; YSI Inc., Yellow Springs, Ohio), the oxygen concentrations in the headspace of the batch culture container were found to be constant throughout the incubation period, while the dissolved oxygen levels in the liquid medium slowly declined to unde- tectable levels during exponential growth of the bacteria. Batch cultures were incubated for 6 to 7 h when no carbon dioxide was present or 8 h when 7% carbon dioxide was included in the gas mixture. Samples were removed from the culture at regular time intervals, and readings of the optical density at 600 nm were taken and cell counts were determined prior to ethanol treatment of the culture samples. Proteins were precipitated and cells were killed in 4 volumes of ethanol for a minimum of 12 h. Precipitation by this method has been shown to be complete, and the removal of bacteria prior to treatment with ethanol is not necessary to quantify toxin production (16, 17). The mixtures were centrifuged at 500 ⫻ g for 10 min, the supernatant was removed, and the pellet was partially desiccated to remove excess liquid. The pellets were resuspended in 1 ml of phosphate buffer solution containing 1.0% fetal calf serum and 0.05% Tween 20 and were centrifuged at approximately 500 ⫻ g for 5 min to remove insoluble cell debris in the preparation for determination of TSST-1 concentrations by en- zyme-linked immunosorbent assay (ELISA).
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Toxin Profiling of Staphylococcus aureus Strains Involved in Varicella Superinfection

Toxin Profiling of Staphylococcus aureus Strains Involved in Varicella Superinfection

The most common complications of varicella are bacterial skin and soft tissue infections, generally due to Staphylococcus aureus and group A beta-hemolytic streptococci. The aim of this study was to characterize the toxin and antibiotic resistance profiles of S. aureus isolates involved in varicella complications. Between 2002 and 2007, the French Reference Centre for Staphylococci collected 58 S. aureus isolates involved in varicella superinfection. All the isolates were characterized by screening for 12 toxin genes, agr typing, and mecA gene detection; some isolates were also studied by spa typing, multilocus sequence typing (MLST), and resistance profiling. A major toxin gene was detected in 53% (31/58) of the isolates (genes for exfoliative toxins A and B, 17.2%; Panton-Valentine leukocidin gene, 8.6%; toxic shock syndrome toxin 1 gene, 27.6%). Most clinical manifestations were directly compatible with the classical activity of these toxins. Nineteen isolates (33%) were resistant to methicillin, and 12 of these isolates belonged to an emerging agr-2, ST5 clone that harbors the toxic shock syndrome toxin 1 gene. These data should be considered in the management and treatment of patients with varicella complicated by S. aureus superinfection. Antibiotics that decrease toxin production, such as clindamycin, may provide benefit, and their efficacy against bacterial superinfections in children with varicella should be studied.
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Staphylococcus aureus Exotoxins Are Present In Vivo in Tampons

Staphylococcus aureus Exotoxins Are Present In Vivo in Tampons

Staphylococcal toxic shock syndrome toxin 1 (TSST-1) is the cause of menstrual toxic shock syndrome (mTSS) associated with vaginal colonization by Staphylococcus aureus. In this pilot study, we measured TSST-1 and alpha-toxin, another exotoxin, on used tampons from four healthy women with S. aureus on tampons and from two women with tampon-associated mTSS. Tampons from all six women were sectioned into approximately 0.5-cm 3 pieces, some containing menstrual blood and some lacking menstrual blood. The pH of tampon sections with or without menstrual blood was neutral. S. aureus CFU were present in tampon sections at approximately equivalent counts (total counts were 1 ⴛ 10 8 to 2 ⴛ 10 9 CFU/tampon). TSST-1 (2 to 80 ␮ g/tampon) and alpha-toxin (28 to 30 ␮ g/tampon) were present only in the sections containing little or no menstrual blood (low hemoglobin density). In the tampons from TSS patients, the cytokine gamma interferon (IFN- ␥ ) was detected only in menstrual-blood-containing sections, whereas the chemokines macrophage inflammatory protein 3 ␣ and interleukin-8 were detected in all sections. Thus, IFN- ␥ was being produced systemically, whereas the chemokines were being produced both locally by epithelial cells and systemically. The data show that S. aureus exotoxins can be identified in tampons ex vivo in sites with low hemoglobin density.
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Epidermal HLA DR and the enhancement of cutaneous reactivity to superantigenic toxins in psoriasis

Epidermal HLA DR and the enhancement of cutaneous reactivity to superantigenic toxins in psoriasis

Streptococcal and staphylococcal superantigens (SAg’s) have been implicated in the pathogenesis of inflammatory skin diseases, but the mechanisms by which these toxins act are unknown. The present study assessed the ability of nanogram quantities of topically applied purified toxic shock syndrome toxin-1 (TSST-1), staphylococcal enterotoxin type B, and streptococcal pyrogenic enterotoxin types A and C to induce inflammatory reactions in clinically uninvolved skin of normal controls and subjects with psoriasis, atopic dermatitis, and lichen planus. These SAg’s triggered a significantly greater inflammatory skin response in psoriatics than in normal control subjects or in subjects with atopic dermatitis or lichen planus. Surprisingly, skin biopsies did not exhibit the T-cell receptor Vb stimulatory properties predicted for SAg-induced skin reactions. By 6 hours after patch testing with SAg’s, TNF-a mRNA had increased in the epidermis (but not the dermis) in biopsies from psoriatics, compared with controls. Immunohistochemical studies revealed significantly higher HLA-DR expression in keratinocytes from psoriatics than from controls. However, a mutant TSST-1 protein that fails to bind HLA-DR did not elicit an inflammatory skin reaction. These results indicate that keratinocyte expression of HLA-DR enhances inflammatory skin responses to SAg’s. They may also account for previous studies failing to demonstrate selective expansion of T-cell receptor Vbs in psoriatics colonized with SAg-producing Staphylococcus aureus, and they identify a novel T cell–independent mechanism by […]
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