scholarly journals Fosfomycin Reduces CD15s-Related Antigen Expression of Streptococcus pyogenes

1998 ◽  
Vol 42 (5) ◽  
pp. 1083-1087 ◽  
Author(s):  
Katsuhiko Hirota ◽  
Kinya Murakami ◽  
Ken Nemoto ◽  
Tsuneko Ono ◽  
Takashi Matsuo ◽  
...  
Keyword(s):  
Streptococcus Pyogenes ◽  
Surface Antigen ◽  
Phosphonic Acid ◽  
Laser Scanning ◽  
Antigen Expression ◽  
Host Cells ◽  
Enzyme Linked Immunosorbent Assay ◽  
Sialyl Lewis ◽  
Cell Enzyme ◽  
Selectin Family

ABSTRACT We have previously shown the immunological mimicry of human sialyl-Lewisx (CD15s) by a surface antigen ofStreptococcus pyogenes. This mimicking surface antigen may act as a ligand to the selectin family and may induce antibody production against CD15s on host cells, suggesting a possible role in the pathogenesis of S. pyogenes. In this study, the effects of antibiotics on the CD15s-related antigen expression of S. pyogenes were examined at a concentration below the MIC (sub-MIC). The amounts of CD15s on the surfaces of S. pyogenes cells and on the surfaces of S. pyogenesbiofilms were determined by a whole-cell enzyme-linked immunosorbent assay and by laser scanning fluorescence microscopy, respectively, by using an anti-CD15s monoclonal antibody. At the sub-MICs, fosfomycin (1R,2S-1,2-epoxypropyl phosphonic acid), its enantiomer (1S,2R-1,2-epoxypropyl phosphonic acid), and benzylpenicillin significantly inhibited the CD15s expression of all strains studied. The effects of fosfomycin and its enantiomer on biofilms were also observed by scanning electron microscopy. Incubation of S. pyogenes with the sub-MIC of fosfomycin or its enantiomer, which has no antibacterial activity, reduced the amount of CD15s on the biofilm surface and made it smooth. These results suggest that fosfomycin or its enantiomer might be useful for preventing S. pyogenes adherence to human CD15s receptors and the resulting immunological pathogenicity.

scholarly journals Proteomic Analysis and Identification of Streptococcus pyogenes Surface-Associated Proteins

2006 ◽  
Vol 189 (5) ◽  
pp. 1514-1522 ◽  
Author(s):  
Anatoly Severin ◽  
Elliott Nickbarg ◽  
Joseph Wooters ◽  
Shakey A. Quazi ◽  
Yury V. Matsuka ◽  
...  
Keyword(s):  
Streptococcus Pyogenes ◽  
Vaccine Development ◽  
Wide Spectrum ◽  
Enzyme Linked Immunosorbent Assay ◽  
Bacterial Surface ◽  
Cell Enzyme ◽  
Specific Antisera ◽  
Significant Burden ◽  
Associated Proteins ◽  
Surface Localization

ABSTRACT Streptococcus pyogenes is a gram-positive human pathogen that causes a wide spectrum of disease, placing a significant burden on public health. Bacterial surface-associated proteins play crucial roles in host-pathogen interactions and pathogenesis and are important targets for the immune system. The identification of these proteins for vaccine development is an important goal of bacterial proteomics. Here we describe a method of proteolytic digestion of surface-exposed proteins to identify surface antigens of S. pyogenes. Peptides generated by trypsin digestion were analyzed by multidimensional tandem mass spectrometry. This approach allowed the identification of 79 proteins on the bacterial surface, including 14 proteins containing cell wall-anchoring motifs, 12 lipoproteins, 9 secreted proteins, 22 membrane-associated proteins, 1 bacteriophage-associated protein, and 21 proteins commonly identified as cytoplasmic. Thirty-three of these proteins have not been previously identified as cell surface associated in S. pyogenes. Several proteins were expressed in Escherichia coli, and the purified proteins were used to generate specific mouse antisera for use in a whole-cell enzyme-linked immunosorbent assay. The immunoreactivity of specific antisera to some of these antigens confirmed their surface localization. The data reported here will provide guidance in the development of a novel vaccine to prevent infections caused by S. pyogenes.

The development of exo-erythrocytic schizonts ofPlasmodium berghei in vitrofrom gamma-irradiated and non-irradiated sporozoites: a study using confocal laser scanning microscopy

Parasitology ◽  
1991 ◽  
Vol 103 (1) ◽  
pp. 17-21 ◽  
Author(s):  
R. E. Sinden ◽  
A. Couchman ◽  
A. Suhrbier ◽  
F. Marsh ◽  
L. Winger ◽  
...  
Keyword(s):  
Laser Scanning ◽  
De Novo ◽  
Parasitophorous Vacuole ◽  
Hepatoma Cell ◽  
Specific Antigen ◽  
Antigen Expression ◽  
Laser Scanning Microscopy ◽  
Host Cells ◽  
Confocal Scanning Laser Microscopy ◽  
Confocal Laser

Confocal scanning laser microscopy has been used to study the distribution of antigens expressed by the liver stages ofPlasmodium bergheiin cultured hepatoma cells. The 3-dimensional images obtained of intact parasites clearly show complex patterns of antigen expression not apparent when using conventional IFAT or immunoelectron microscopy. A liver-stage specific antigen (Pbl 1) was shown to be confined to the parasitophorous vacuole; the vacuole has extensive diverticulae extending into the host cell. Small parasites were detected for the first time in ‘mature’ cultures. These did not represent a distinct population, but the ‘tail’ of a broad continuum of parasite sizes. Irradiated sporozoites produce a transient population of slow-growing parasites which express a very limited range of antigensde novoin the invaded hepatoma cell. A comparison of the reactivity of text-abstract EE parasites with anti-circumsporozoite antibody and with anti-Pbl 1 suggests that the former reagent may reliably be used to identify sporozoites invading host cells, but should not be used to determine the number of parasites that successfully undergo intrahepatic development. Anti-Pbl-1 indicates on 33% of invaded sporozoites identified by anti-CSP subsequently differentiate.

scholarly journals Surface antigen expression in spleen cells of C57Bl/6 mice during ageing: influence of sex and parity

1997 ◽  
Vol 107 (3) ◽  
pp. 593-600 ◽  
Author(s):  
F. BARRAT ◽  
B. M. LESOURD ◽  
A. LOUISE ◽  
H.-J. BOULOUIS ◽  
S. VINCENT-NAULLEAU ◽  
...  
Keyword(s):  
Surface Antigen ◽  
Antigen Expression ◽  
Spleen Cells ◽  
Surface Antigen Expression

Direct IFNluence of interferon-γ on proliferation and cell-surface antigen expression of non-small cell lung cancer cells

Lung Cancer ◽  
2000 ◽  
Vol 30 (3) ◽  
pp. 169-174 ◽  
Author(s):  
Tokujiro Yano ◽  
Kenji Sugio ◽  
Koji Yamazaki ◽  
Shinichiro Kase ◽  
Masafumi Yamaguchi ◽  
...  
Keyword(s):  
Lung Cancer ◽  
Cell Surface ◽  
Small Cell Lung Cancer ◽  
Cancer Cells ◽  
Surface Antigen ◽  
Antigen Expression ◽  
Interferon Γ ◽  
Small Cell ◽  
Small Cell Lung ◽  
Surface Antigen Expression

scholarly journals A distinct 5' flanking var gene region regulates Plasmodium falciparum variant erythrocyte surface antigen expression in placental malaria

2002 ◽  
Vol 45 (1) ◽  
pp. 155-167 ◽  
Author(s):  
Aleida Vazquez-Macias ◽  
Perla Martinez-Cruz ◽  
Maria Cristina Castaneda-Patlan ◽  
Christine Scheidig ◽  
Jurg Gysin ◽  
...  
Keyword(s):  
Plasmodium Falciparum ◽  
Surface Antigen ◽  
Placental Malaria ◽  
Antigen Expression ◽  
Gene Region ◽  
Erythrocyte Surface ◽  
Surface Antigen Expression ◽  
Var Gene

scholarly journals Development and evaluation of an in-house ELISA to detect hepatitis B virus surface antigen in resource-limited settings

2014 ◽  
Vol 39 (2) ◽  
pp. 65-68 ◽  
Author(s):  
K Fatema ◽  
S Tabassum ◽  
A Nessa ◽  
M Jahan
Keyword(s):  
Hepatitis B Virus ◽  
Hepatitis B ◽  
Surface Antigen ◽  
Hbv Infection ◽  
Health Concern ◽  
Enzyme Linked Immunosorbent Assay ◽  
Virus Surface ◽  
B Virus ◽  
Commercial Kits ◽  
Checkerboard Titration

Hepatitis B virus (HBV) infection is of global public health concern. Among various serological tests used for the diagnosis and screening of HBV infection, the enzyme-linked immunosorbent assay (ELISA) to detect hepatitis B surface antigen (HbsAg) is most widely used. The present study was designed to develop and standardize a cost effective in-house ELISA for the detection of HbsAg and compare its performance with two established commercial kits. The concentrations of coating antibody, conjugates and sera were fixed by checkerboard titration. Using known HBsAg positive and negative sera, four different concentrations (1, 0.5, 0.25 and 0.125 ?g/well) of coating anti-HBs were applied. Similarly, serial dilutions of patients’ sera (1 in 2, 1 in 3, 1 in 5 and 1 in 9) and conjugates (1 in 2, 1 in 3, 1 in 5, 1 in 9 and 1 in 17) were evaluated by checkerboard titration. The optimal concentration of coating antibody was determined at 0.25 ?g/well and 1 in 9 dilution for both conjugates and sera. The performance comparison of our in-house ELISA showed excellent correlation with two commercial kits (Pearson 0.957, P=0.001 for monoclonal antibody coated kit and Pearson 0.929, P=0.000 for polyclonal antibody coated kit) when OD values were compared. All commercial kit proven positive samples was positive while all negative samples were negative with the in-house ELISA resulting in 100% sensitivity and specificity. The results of our study demonstrated that our inhouse ELISA for detection of HBsAg was equally as sensitive and specific as two well-known commercial kits. Thus, this system may be a useful tool for diagnostic and screening purposes, as well as outbreak investigations. DOI: http://dx.doi.org/10.3329/bmrcb.v39i2.19644 Bangladesh Med Res Counc Bull 2013; 39: 65-68

scholarly journals The inhibitory effects of toothpaste and mouthwash ingredients on the interaction between the SARS-CoV-2 spike protein and ACE2, and the protease activity of TMPRSS2, in vitro

2021 ◽  
Author(s):  
Riho Tateyama-Makino ◽  
Mari Abe-Yutori ◽  
Taku Iwamoto ◽  
Kota Tsutsumi ◽  
Motonori Tsuji ◽  
...  
Keyword(s):  
Serine Protease ◽  
Protease Activity ◽  
Oral Care ◽  
Sodium Dodecyl ◽  
Host Cells ◽  
Spike Protein ◽  
Enzyme Linked Immunosorbent Assay ◽  
Inhibitory Effects ◽  
Docking Simulations

Severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) enters host cells when the viral spike protein is cleaved by transmembrane protease serine 2 (TMPRSS2) after binding to the host angiotensin-converting enzyme 2 (ACE2). Since ACE2 and TMPRSS2 are expressed in the mucosa of the tongue and gingiva, the oral cavity seems like it is an entry point for SARS-CoV-2. Daily oral care using mouthwash seems to play an important role in preventing SARS-CoV-2 infection. However, the relationship between daily oral care and the mechanisms of virus entry into host cells is unclear. In this study, we evaluated the inhibitory effects of ingredients that are generally contained in toothpaste and mouthwash on the interaction between the spike protein and ACE2 and on the serine protease activity of TMPRSS2 using an enzyme-linked immunosorbent assay and in vitro enzyme assay, respectively. Both assays detected inhibitory effects of sodium tetradecene sulfonate, sodium N-lauroyl-N-methyltaurate, sodium N-lauroylsarcosinate, sodium dodecyl sulfate, and copper gluconate. Molecular docking simulations suggested that these ingredients could bind to the inhibitor-binding site of ACE2. In addition, tranexamic acid and 6-aminohexanoic acid, which act as serine protease inhibitors, exerted inhibitory effects on TMPRSS2 protease activity. Further experimental and clinical studies are needed to further elucidate these mechanisms. Our findings support the possibility that toothpaste and mouthwash contain ingredients that inhibit SARS-CoV-2 infection.

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