O94 Recognition of Staphylococcus aureus by plasmacytoid dendritic cells is species-specific but not related to alpha-toxin or protein A expression

2007 ◽  
Vol 29 ◽  
pp. S19
Author(s):  
M. Parcina ◽  
C. Wendt ◽  
K. Heeg ◽  
I.B. Bekeredjian-Ding
Keyword(s):  
Staphylococcus Aureus ◽  
Dendritic Cells ◽  
Protein A ◽  
Plasmacytoid Dendritic Cells ◽  
Alpha Toxin ◽  
Species Specific

scholarly journals Corneal virulence of Staphylococcus aureus: roles of alpha-toxin and protein A in pathogenesis.

1994 ◽  
Vol 62 (6) ◽  
pp. 2478-2482 ◽  
Author(s):  
M C Callegan ◽  
L S Engel ◽  
J M Hill ◽  
R J O'Callaghan
Keyword(s):  
Staphylococcus Aureus ◽  
Protein A ◽  
Alpha Toxin

scholarly journals Characterization of species-specific genes regulated by E2-2 in human plasmacytoid dendritic cells

2015 ◽  
Vol 5 (1) ◽  
Author(s):  
Menglan Cheng ◽  
Xuyuan Zhang ◽  
Haisheng Yu ◽  
Peishuang Du ◽  
Joël Plumas ◽  
...  
Keyword(s):  
Dendritic Cells ◽  
Plasmacytoid Dendritic Cells ◽  
Species Specific

scholarly journals mgr, a Novel Global Regulator in Staphylococcus aureus

2003 ◽  
Vol 185 (13) ◽  
pp. 3703-3710 ◽  
Author(s):  
Thanh T. Luong ◽  
Steven W. Newell ◽  
Chia Y. Lee
Keyword(s):  
Staphylococcus Aureus ◽  
Capsular Polysaccharide ◽  
Polyacrylamide Gel Electrophoresis ◽  
Protein A ◽  
Sodium Dodecyl ◽  
Binding Motif ◽  
Transcriptional Level ◽  
Virulence Determinants ◽  
Alpha Toxin ◽  
Extracellular Protein Production

ABSTRACT The virulence determinants of Staphylococcus aureus are coordinately controlled by several unlinked chromosomal loci. Here, we report the identification of CYL5614, derived from strain Becker, with a mutation that affects the expression of type 8 capsular polysaccharide (CP8), nuclease, alpha-toxin, coagulase, protease, and protein A. This novel locus, named mgr, was linked by transposon Tn917 and mapped by three-factorial transduction crosses. The region containing the mgr locus was cloned and sequenced. Deletion mutagenesis and genetic complementation showed that the locus consisted of one gene, mgrA. Interestingly, mgrA-null mutants exhibited a phenotype opposite to that of CYL5614. This was due to a T-to-C mutation upstream of mgrA that resulted in a four- to eightfold increase in mgrA transcription in strain CYL5614. Thus, these results indicate that mgrA is an activator of CP8 and nuclease but a repressor of alpha-toxin, coagulase, protease, and protein A. In addition, sodium dodecyl sulfate-polyacrylamide gel electrophoresis analyses showed that the mgr locus profoundly affected extracellular protein production, suggesting that the locus may regulate many other genes as well. The translated MgrA protein has a region of significant homology, which includes the helix-turn-helix DNA-binding motif, with the Escherichia coli MarR family of transcriptional regulators. Northern slot blot analyses suggested that mgr affected CP8, alpha-toxin, nuclease, and protein A at the transcriptional level.

scholarly journals Regulation of agr-Dependent Virulence Genes in Staphylococcus aureus by RNAIII from Coagulase-Negative Staphylococci

1998 ◽  
Vol 180 (12) ◽  
pp. 3181-3186 ◽  
Author(s):  
Karin Tegmark ◽  
Eva Morfeldt ◽  
Staffan Arvidson
Keyword(s):  
Staphylococcus Aureus ◽  
Cell Surface ◽  
Serine Protease ◽  
Protein A ◽  
Surface Proteins ◽  
Open Reading Frames ◽  
Alpha Toxin ◽  
Coagulase Negative Staphylococci ◽  
Cell Surface Proteins ◽  
Genes Encoding

ABSTRACT Many of the genes coding for extracellular toxins, enzymes, and cell surface proteins in Staphylococcus aureus are regulated by a 510-nucleotide (nt) RNA molecule, RNAIII. Transcription of genes encoding secreted toxins and enzymes, includinghla (alpha-toxin), saeB (enterotoxin B),tst (toxic shock syndrome toxin 1), and ssp(serine protease), is stimulated, while transcription of genes encoding cell surface proteins, like spa (protein A) andfnb (fibronectin binding proteins), is repressed. Besides being a regulator, RNAIII is also an mRNA coding for staphylococcal delta-lysin. We have identified RNAIII homologs in three different coagulase-negative staphylococci (CoNS), i.e., Staphylococcus epidermidis, Staphylococcus simulans, andStaphylococcus warneri. RNAIII from these CoNS turned out to be very similar to that of S. aureus and contained open reading frames encoding delta-lysin homologs. Though a number of big insertions and/or deletions have occurred, mainly in the 5′ half of the molecules, the sequences show a high degree of identity, especially in the first 50 and last 150 nt. The CoNS RNAIII had the ability to completely repress transcription of protein A in an RNAIII-deficientS. aureus mutant and the ability to stimulate transcription of the alpha-toxin and serine protease genes. However, the stimulatory effect was impaired compared to that of S. aureus RNAIII, suggesting that these regulatory functions are independent. By creating S. epidermidis-S. aureus RNAIII hybrids, we could also show that both the 5′ and 3′ halves of the RNAIII molecule are involved in the transcriptional regulation of alpha-toxin and serine protease mRNAs in S. aureus.

scholarly journals Nicotiana spp. for the Expression and Purification of Functional IgG3 Antibodies Directed Against the Staphylococcus aureus Alpha Toxin

2021 ◽  
Vol 3 ◽  
Author(s):  
P. Opdensteinen ◽  
S. Meyer ◽  
J. F. Buyel
Keyword(s):  
Staphylococcus Aureus ◽  
Binding Capacity ◽  
Protein A ◽  
Adaptive Immune Response ◽  
Hybridoma Cells ◽  
Alpha Toxin ◽  
In Planta ◽  
Affinity Ligand ◽  
Igg3 Subclass ◽  
Drug Resistant Strains

Immunoglobulin subclass IgG1 is bound and neutralized effectively by Staphylococcus aureus protein A, allowing the bacterium to evade the host’s adaptive immune response. In contrast, the IgG3 subclass is not bound by protein A and can be used to treat S. aureus infections, including drug-resistant strains such as methicillin-resistant Staphylococcus aureus (MRSA). However, the yields of recombinant IgG3 are generally low because this subclass is prone to degradation, and recovery is hindered by the inability to use protein A as an affinity ligand for antibody purification. Here, we investigated plants (Nicotiana spp.) as an alternative to microbes and mammalian cell cultures for the production of an IgG3 antibody specific for the S. aureus alpha toxin. We targeted recombinant IgG3 to different subcellular compartments and tested different chromatography conditions to improve recovery and purification. Finally, we tested the antigen-binding capacity of the purified antibodies. The highest IgG3 levels in planta (>130 mg kg−1 wet biomass) were achieved by targeting the endoplasmic reticulum or apoplast. Although the purity of IgG3 exceeded 95% following protein G chromatography, product recovery requires further improvement. Importantly, the binding affinity of the purified antibodies was in the nanomolar range and thus comparable to previous studies using murine hybridoma cells as the production system.

scholarly journals MsrR, a Putative Cell Envelope-Associated Element Involved in Staphylococcus aureus sarA Attenuation

2003 ◽  
Vol 47 (8) ◽  
pp. 2558-2564 ◽  
Author(s):  
Jutta Rossi ◽  
Markus Bischoff ◽  
Akihito Wada ◽  
Brigitte Berger-Bächi
Keyword(s):  
Staphylococcus Aureus ◽  
Virulence Factors ◽  
Regulatory Network ◽  
Cell Envelope ◽  
Protein A ◽  
Virulence Gene ◽  
Exponential Growth Phase ◽  
Alpha Toxin ◽  
Altered Expression ◽  
Virulence Gene Expression

ABSTRACT A novel membrane-associated protein, MsrR, was identified in Staphylococcus aureus which affects resistance to methicillin and teicoplanin, as well as the synthesis of virulence factors. MsrR belongs to the LytR-CpsA-Psr family of cell envelope-related transcriptional attenuators and was shown to be inducible by cell wall-active agents, such as β-lactams, glycopeptides, and lysostaphin. The expression of msrR peaked in the early exponential growth phase and decreased sharply thereafter. msrR mutants showed increased sarA transcription and an earlier and higher expression of RNAIII, resulting in altered expression of virulence factors such as alpha-toxin and protein A. These observations suggest that MsrR is a new component involved in sarA attenuation and the regulatory network controlling virulence gene expression in S. aureus.

scholarly journals Diagnostic utility of plasmacytoid dendritic cells in dermatopathology

2021 ◽  
Vol 87 ◽  
pp. 3-13
Author(s):  
Tara Bardawil ◽  
Samar Khalil ◽  
Mazen Kurban ◽  
Ossama Abbas
Keyword(s):  
Dendritic Cells ◽  
Dendritic Cell ◽  
Plasmacytoid Dendritic Cell ◽  
Protein A ◽  
Surrogate Marker ◽  
Plasmacytoid Dendritic Cells ◽  
Current Evidence ◽  
Histopathological Diagnosis ◽  
Type I ◽  
Resistance Protein

Differentiating cutaneous diseases that mimic each other clinically and histopathologically can at times be a challenging task for the dermatopathologist. At the same time, differentiation of entities with overlapping features may be crucial for patient management. Although not seen in normal skin, plasmacytoid dendritic cells usually infiltrate the skin in several infectious, inflammatory/autoimmune and neoplastic entities. Plasmacytoid dendritic cells can be identified in tissue using specific markers such as CD123 and/or blood-derived dendritic cell antigen-2. Plasmacytoid dendritic cells are the most potent producers of type I interferons and their activity may therefore be assessed indirectly in tissue using human myxovirus resistance protein A, a surrogate marker for type I interferon production. In recent years, accumulating evidence has established the utility of evaluating for specific plasmacytoid dendritic cell-related parameters (plasmacytoid dendritic cell content, distribution and clustering and/ or human myxovirus resistance protein A expression) as a diagnostic tool in differentiating cutaneous diseases with overlapping features such as the alopecias, lupus and its mimics, and neoplastic entities. In this review, we provide an update on the current evidence on this topic and on the contexts where this can be a useful adjunct to reach the histopathological diagnosis.

Sign in / Sign up

Export Citation Format

Share Document