Objective: The docking and superantigen activity sites of staphylococcal enterotoxin-like W (SElW) and T cell receptor (TCR) were predicted, and its SElW was cloned, expressed and purified. Methods: AlphaFold was used to predict the 3D structure of SElW protein monomers, and the protein models were evaluated with the help of the SAVES online server from ERRAT, Ramachandran plot, and Verify_3D. The ZDOCK server simulates the docking conformation of SElW and TCR, and the amino acid sequences of SElW and other serotype enterotoxins were aligned. The primers were designed to amplify selw, and the fragment was recombined into the pMD18-T vector and sequenced. Then recombinant plasmid pMD18-T was digested with BamHⅠand Hind Ⅲ. The target fragment was recombined into the expression plasmid pET-28a(+). After identification of the recombinant plasmid, the protein expression was induced by isopropyl-beta-D- thiogalactopyranoside. The SElW expressed in the supernatant was purified by affinity chromatography and quantified by the BCA method. Results: The predicted three-dimensional structure showed that the SElW protein was composed of two domains, the amino-terminal and the carboxy-terminal. The amino-terminal domain was composed of 3 α-helices and 6 β-sheets, and the carboxy-terminal domain included 2 α-helices and 7 antiparallel β-sheets composition. The overall quality factor score of the SElW protein model was 98.08, with 93.24% of the amino acids having a Verify_3D score ≥0.2 and no amino acids located in disallowed regions. The docking conformation with the highest score (1 521.328) was selected as the analysis object, and the 19 hydrogen bonds between the corresponding amino acid residues of SElW and TCR were analyzed by PyMOL. Combined with sequence alignment and the published data, this study predicted and found five important superantigen active sites, namely Y18, N19, W55, C88, and C98. The highly purified soluble recombinant protein SElW was obtained with cloning, expression, and protein purification. Conclusions: The study found five superantigen active sites in SElW protein that need special attention and successfully constructed and expressed the SElW protein, which laid the foundation for further exploration of the immune recognition mechanism of SElW.
Humans ; Enterotoxins/genetics* ; Superantigens/genetics* ; Catalytic Domain ; Selenoprotein W/metabolism* ; Receptors, Antigen, T-Cell

Staphylococcus aureus commonly colonizes the skin of atopic dermatitis (AD) patients and contributes to the development and exacerbation of AD. Multiple factors are associated with colonization of AD skin by S. aureus, including the strength of S. aureus-corneocyte adhesion, deficiency of antimicrobial peptides, decreased levels of filaggrin and filaggrin degradation products, overexpressed Th2/Th17 cytokines, microbial dysbiosis and altered lipid profiles. S. aureus colonization on AD skin causes skin barrier dysfunction through virulence factors such as superantigens (toxins), enzymes and other proteins. Furthermore, colonization of AD skin by S. aureus exacerbates AD and may contribute to microbial dysbiosis, allergen sensitization, Th2/Th17 polarization, development of atopic march and food allergy in AD patients. Skin colonization of S. aureus, particularly methicillin-resistant S. aureus (MRSA), is one of the major challenges commonly encountered in the management of AD. Bleach bath, and topical or systemic antibiotics could be used to control S. aureus infection on AD skin. However, careful use of antibiotics is required to control the occurence of MRSA. Recently, various strategies, including microbiome transplant, monoclonal antibodies against virulent toxins, vaccines and recombinant phage endolysin, have been studied to control S. aureus infection on AD skin. Further advances in our understanding of S. aureus could provide us with ways to manage S. aureus colonization more effectively in AD patients.
Anti-Bacterial Agents ; Antibodies, Monoclonal ; Bacteriophages ; Baths ; Colon ; Cytokines ; Dermatitis, Atopic ; Dysbiosis ; Food Hypersensitivity ; Humans ; Methicillin Resistance ; Methicillin-Resistant Staphylococcus aureus ; Microbiota ; Peptides ; Skin ; Staphylococcus aureus ; Staphylococcus ; Superantigens ; Vaccines ; Virulence Factors

OBJECTIVES: Pathophysiology of chronic rhinosinusitis (CRS) is very complex and has not yet been clearly understood. To date, various factors have been researched to have relations with the pathogenesis of CRS, such as superantigens and biofilms. Recently, we found an unusual pathological finding in patients with CRS, and we called this new entity as bacteria ball (or bioball). In this study, we analyze the clinical characteristics of bacteria ball occurred in CRS. METHODS: This study enrolled consecutive 247 patients with CRS who underwent functional endoscopic sinus surgery from January 2015 to August 2016. The diagnosis of bacterial ball was made when negative in Gomori-methenamine-silver stain and positive in Gram stain. Histologically, bacterial ball was defined as acellular mucous materials with bacterial colonies and inflammatory cell infiltrates. We compared clinical data and computed tomography (CT) findings between fungal and bacterial balls. RESULTS: Six cases (2.4%) of CRS were confirmed histologically as bacterial ball. Most of them were found in the maxillary sinus of CRS without nasal polyposis (66.7%). Bacterial ball was green or brown colored materials similar to fungal ball which was harder and tightly adherent to the antral mucosa. Compared to fungal ball, patients with bacterial ball showed significantly less peripheral eosinophils (P=0.011) and calcification in CT scans (P=0.003). CONCLUSION: Bacterial ball is unusual findings occurred in patient with CRS which is different from fungal ball and biofilm. For diagnosis of bacterial ball, Gram stain is essentially required to identify bacterial colonies. Bacterial ball might appear to be evidence of a new strategy for living in the paranasal sinuses.
Bacteria ; Biofilms ; Diagnosis ; Eosinophils ; Fungi ; Humans ; Maxillary Sinus ; Mucous Membrane ; Paranasal Sinuses ; Sinusitis ; Superantigens ; Tomography, X-Ray Computed

Objective: To analyze the characteristics of super-antigen (SAg) of group A Streptococcus pyogenes (GAS), isolated from patients with scarlet fever or pharyngeal infections in Beijing between 2015-2017. Methods: Throat swab specimens from patients with scarlet fever or pharyngeal infections were collected and tested for GAS. Eleven currently known SAg genes including SpeA, speC, speG, speH, speI, speJ, speK, speL, speM, smeZ and ssa were tested by real-time PCR while M protein genes (emm genes) were amplified and sequenced by PCR. Results: A total of 377 GAS were isolated from 6 801 throat swab specimens, with the positive rate as 5.5%. There were obvious changes noticed among speC, speG, speH and speK in three years. A total of 45 SAg genes profiles were observed, according to the SAgs inclusion. There were significant differences appeared in the frequencies among two of the highest SAg genes profiles between emm1 and emm12 strains (χ(2)=38.196, P<0.001; χ(2)=72.310, P<0.001). There also appeared significant differences in the frequencies of speA, speH, speI and speJ between emm1 and emm12 strains (χ(2)=146.154, P<0.001; χ(2)=52.31, P<0.001; χ(2)=58.43, P<0.001; χ(2)=144.70, P<0.001). Conclusions: Obvious changes were noticed among SAg genes including speC, speG, speH and speK from patients with scarlet fever or pharyngeal infections in Beijing between 2015-2017. SAg genes including speA, speH, speI and speJ appeared to be associated with the emm 1 and emm 12 strains. More kinds of SAg genes profiles were isolated form GAS but with no significant differences seen in the main SAg genes profiles, during the epidemic period.
Antigens, Bacterial/genetics* ; Bacterial Outer Membrane Proteins ; Bacterial Proteins ; Beijing/epidemiology* ; China/epidemiology* ; Exotoxins ; Female ; Humans ; Membrane Proteins ; Pharyngitis/microbiology* ; Pharynx/microbiology* ; Pregnancy ; Pregnancy Complications, Infectious/microbiology* ; Real-Time Polymerase Chain Reaction ; Scarlet Fever/microbiology* ; Streptococcal Infections ; Streptococcus pyogenes/isolation & purification* ; Superantigens/genetics*

Atopic dermatitis (AD) is characterized by disturbances in epidermal barrier functions and the hyperactive immune response. Staphylococcus aureus (S. aureus) can be cultured from 90% of AD skin lesions and can exacerbate or contribute to the persistent skin inflammation in AD by secreting toxins with superantigenic properties. Superantigens can induce mast cell (MC) degranulation after penetrating the epidermal barrier. The role of MCs in AD is suggested by the increase in the MC number and MC activation. MCs are activated for degranulation and mediator release by allergens that cross-link IgE molecules or by microbial products. Therefore, MCs may be critically involved in the pathogenesis of AD. However, the understanding mechanisms of MC degranulation by S. aureus in relation to AD have still not been fully elucidated. In this study, we found that live S. aureus or methicillin-resistant S. aureus (MRSA) but not heat-killed bacteria induced MC degranulation. The heat-treatment partially inhibited MC degranulation by conditioned media (CM) of S. aureus or MRSA. The calcium chelator ethylene glycol tetraacetic acid (EGTA) did not block MC degranulation induced by live S. aureus or MRSA, but EGTA-treatment partially inhibited MC degranulation by CM from S. aureus or MRSA. These results suggest that live S. aureus and MRSA can degranulate MCs via direct interaction which may be important role in AD.
Allergens ; Bacteria ; Calcium ; Culture Media, Conditioned ; Dermatitis, Atopic ; Egtazic Acid ; Humans* ; Immunoglobulin E ; Inflammation ; Mast Cells ; Methicillin Resistance ; Methicillin-Resistant Staphylococcus aureus ; Skin ; Staphylococcus aureus ; Superantigens

Atopic dermatitis (AD) is characterized by disturbances in epidermal barrier functions and the hyperactive immune response. Staphylococcus aureus (S. aureus) can be cultured from 90% of AD skin lesions and can exacerbate or contribute to the persistent skin inflammation in AD by secreting toxins with superantigenic properties. Superantigens can induce mast cell (MC) degranulation after penetrating the epidermal barrier. The role of MCs in AD is suggested by the increase in the MC number and MC activation. MCs are activated for degranulation and mediator release by allergens that cross-link IgE molecules or by microbial products. Therefore, MCs may be critically involved in the pathogenesis of AD. However, the understanding mechanisms of MC degranulation by S. aureus in relation to AD have still not been fully elucidated. In this study, we found that live S. aureus or methicillin-resistant S. aureus (MRSA) but not heat-killed bacteria induced MC degranulation. The heat-treatment partially inhibited MC degranulation by conditioned media (CM) of S. aureus or MRSA. The calcium chelator ethylene glycol tetraacetic acid (EGTA) did not block MC degranulation induced by live S. aureus or MRSA, but EGTA-treatment partially inhibited MC degranulation by CM from S. aureus or MRSA. These results suggest that live S. aureus and MRSA can degranulate MCs via direct interaction which may be important role in AD.
Allergens ; Bacteria ; Calcium ; Culture Media, Conditioned ; Dermatitis, Atopic ; Egtazic Acid ; Humans* ; Immunoglobulin E ; Inflammation ; Mast Cells ; Methicillin Resistance ; Methicillin-Resistant Staphylococcus aureus ; Skin ; Staphylococcus aureus ; Superantigens

BACKGROUND: Burn wounds lack normal barriers that protect against pathogenic bacteria, and burn patients are easily colonized and infected by Staphylococcus aureus. Toxic shock syndrome (TSS) is a rare but fatal disease caused by S. aureus. A lack of detectable antibodies to TSS toxin-1 (TSST-1) in serum indicates susceptibility to TSS. METHODS: A total of 207 patients (169 men and 38 women; median age, 42.5 yr) admitted to a burn center in Korea were enrolled in this study. The serum antibody titer to TSST-1 was measured by sandwich ELISA. S. aureus isolates from the patients' nasal swab culture were tested for TSST-1 toxin production by PCR-based detection of the TSST-1 toxin gene. RESULTS: One hundred seventy-four (84.1%) patients showed positive results for antibody against TSST-1. All patients aged > or =61 yr (n=28) and <26 months (n=7) were positive for the anti-TSST-1 antibody. S. aureus was isolated from 70 patients (33.8%), and 58.6% of the isolates were methicillin resistant. Seventeen patients were colonized with TSST-1-producing S. aureus. The antibody positivity in these 17 carriers was 88.2%, and the positivity in the non-carriers was 83.7%. CONCLUSIONS: Most burn patients had antibody to TSST-1, and nasal colonization with TSST-1-producing S. aureus was associated with positive titers of anti-TSST-1 antibody. Additionally, patients with negative titers of anti-TSST-1 antibody might be susceptible to TSS.
Adolescent ; Adult ; Aged ; Aged, 80 and over ; Antibodies, Bacterial/*blood ; Bacterial Toxins/genetics/immunology/*metabolism ; Burns/blood/*immunology/*microbiology/pathology ; Child ; Child, Preschool ; Enterotoxins/genetics/immunology/*metabolism ; Enzyme-Linked Immunosorbent Assay ; Female ; Humans ; Infant ; Male ; Middle Aged ; Nasal Cavity/microbiology ; Polymerase Chain Reaction ; Prevalence ; Staphylococcal Infections/epidemiology ; Staphylococcus aureus/isolation & purification/*metabolism ; Superantigens/genetics/immunology/*metabolism ; Young Adult

Protein tyrosine phosphatase-22 (PTPN22) gene encodes lymphoid-specific tyrosine phosphatase (Lyp), an inhibitor of T cell activation. A polymorphism of the PTPN22 gene has been found to be associated with chronic urticaria (CU). We investigated the associations between PTPN22 gene polymorphisms and CU characteristics, including serum specific IgE antibodies response to toxic shock syndrome toxin-1 (TSST-1) and staphylococcal enterotoxin A (SEA). CU patients (n=409) and normal healthy controls (n=388) were enrolled in the present study. Serum specific IgE to TSST-1 and SEA were measured by ImmunoCAP(R). Five PTPN22 single nucleotide polymorphisms, -1123G>C, 1858C>T, 13145A>G, 14943C>T, and 20628A>G, were genotyped. There were no significant differences in genotype or haplotype frequencies of these polymorphisms between the 2 groups. CU patients carrying the GG genotype at 20628A>G (P=0.035) or haplotype 3 [GGG] (P=0.047) had a significantly higher prevalence of serum specific IgE to TSST-1 compared to non-carriers. Similarly, CT/TT genotype at 14943C>T had a significantly higher prevalence of serum specific IgE to SEA (P=0.045). The findings suggest that the PTPN22 gene polymorphisms at 20628A>G and 14943C>T may enhance serum specific IgE responses to TSST-1 and SEA, which may contribute to CU pathogenesis.
Antibodies ; Enterotoxins ; Genotype ; Haplotypes ; Humans ; Immunoglobulin E* ; Polymorphism, Single Nucleotide ; Prevalence ; Shock, Septic ; Superantigens* ; Tyrosine ; Urticaria*

Systemic corticosteroids currently represent the most effective treatment for chronic rhinosinusitis with nasal polyps (CRSwNP), but their long-term use is constrained due to their detrimental side effects. Until recently, development of novel drugs for CRSwNP has been difficult partly due to the absence of a standard animal model of CRSwNP. Exotoxins of Staphylococcus aureus such as staphylococcal enterotoxin B (SEB), are well-known superantigens which can induce a strong immune response; there have been many studies on the association of staphylococcal enterotoxins and development of CRSwNP over the past two decades. Based on previous studies, we invented a mouse model of CRSwNP using SEB. Herein, we explain the protocol development for the mouse model, as well as identify histological and immunological similarities between this mouse model and humans. Furthermore, we describe a study that analyzed the risk factors for CRSwNP such as smoking, and also elaborate on a series of studies that searched for new potential drugs for CRSwNP, including resveratrol, anti-periostin antibody, topical hypoxia-inducible factors, and topical cyclosporine. Based on preceding studies, we have concluded that this mouse model might be a useful tool to investigate the pathophysiology and development of novel drugs for CRSwNP.
Adrenal Cortex Hormones ; Animals ; Cyclosporine ; Enterotoxins ; Exotoxins ; Humans ; Mice* ; Models, Animal ; Nasal Polyps* ; Risk Factors ; Smoke ; Smoking ; Staphylococcus aureus ; Superantigens

OBJECTIVETo investigate superantigen gene profiles of group A Streptococcus (GAS) isolated in Beijing pediatric patients in 2014, and to explore the the relationship between superantigen gene profiles with emm types, and GAS infections with diseases.

METHODSA total of 259 GAS strains were isolated from pediatric patients clinically who diagnosed with scarlet fever and pharyngitis from 36 hospitals in Beijing from May to July, 2014.The Superantigens genes of strains were performed by Real-time PCR (speA, speB, speC, speF, speG, speH, speI, speJ, speK, speL, speM, smeZ, ssa). PCR amplification of GAS strain M protein N gene segments were carried ort; products after sequencing comparison were analyzed to determine the GAS types of emm. The differences in distributions of superantigen genes and emm types of GAS isolates were compared between subgroups.

RESULTSAmong the 259 GAS strains, the detection rates of 13 superantigens were as the following: speA 48.6% (126), speB 99.2% (257), speC 99.2% (257), speF 98.8% (256), speG 98.5% (255), speH 43.6% (113), speI 46.3% (120), speJ 49.0% (127), smeZ 99.2% (257) and ssa 98.5% (255), respectively, however, speK, speL, and speM were not found. Eleven superantigen gene profiles in all were observed (A-K). The percentage of emm1 strains harbored spe A and speJ were 94.2% (113/120), 95.0% (114/120), respectively, which were significantly higher than those of emm12 strains (5.6% (7/124), 5.6% (7/124), respectively; χ(2) = 191.20, 194.80, P < 0.001). The percentage of emm12 strains harbored speH and speI were 83.9% (104/124), 88.7% (110/124), respectively, which were significantly higher than those of emm1 strains (3.3% (4/120), 4.2% (5/120), respectively; χ(2) = 160.30, 174.90, P < 0.001).The superantigen genotypes of GAS strains and emm types, which were isolated from scarlet fever and pharyngitis cases, were not significant different (P > 0.05).

CONCLUSIONThe GSA strains isolated in Beijing pediatric patients in 2014, the relevance ratio of speB, speC, speF, smeZ, speG, ssa were higher than others, while speK, speL, and speM were no detected in any GAS strains. The superantigen genes appeared to be associated with the emm type. Furthermore, emm type distribution and superantigen genes were not different between scalet fever and pharyngitis.

Antigens, Bacterial ; genetics ; Beijing ; Child ; Genotype ; Humans ; Real-Time Polymerase Chain Reaction ; Streptococcal Infections ; microbiology ; Streptococcus pyogenes ; genetics ; immunology ; Superantigens ; genetics