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Neutralization of staphylococcal enterotoxin B by an aptamer antagonist.

ABSTRACT: Staphylococcal enterotoxin B (SEB) is a major virulence factor for staphylococcal toxic shock syndrome (TSS). SEB activates a large subset of the T lymphocytic population, releasing proinflammatory cytokines. Blocking SEB-initiated toxicity may be an effective strategy for treating TSS. Using a process known as systematic evolution of ligands by exponential enrichment (SELEX), we identified an aptamer that can antagonize SEB with nanomolar binding affinity (Kd = 64 nM). The aptamer antagonist effectively inhibits SEB-mediated proliferation and cytokine secretion in human peripheral blood mononuclear cells. Moreover, a PEGylated aptamer antagonist significantly reduced mortality in a "double-hit" mouse model of SEB-induced TSS, established via sensitization with d-galactosamine followed by SEB challenge. Therefore, our novel aptamer antagonist may offer potential therapeutic efficacy against SEB-mediated TSS.

SUBMITTER: Wang K

PROVIDER: S-EPMC4356834 | biostudies-other | 2015 Apr

REPOSITORIES: biostudies-other

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Neutralization of staphylococcal enterotoxin B by an aptamer antagonist.

Wang Kaiyu K Gan Longjie L Jiang Li L Zhang Xianhui X Yang Xiangyue X Chen Min M Lan Xiaopeng X

Antimicrobial agents and chemotherapy 20150126 4

Staphylococcal enterotoxin B (SEB) is a major virulence factor for staphylococcal toxic shock syndrome (TSS). SEB activates a large subset of the T lymphocytic population, releasing proinflammatory cytokines. Blocking SEB-initiated toxicity may be an effective strategy for treating TSS. Using a process known as systematic evolution of ligands by exponential enrichment (SELEX), we identified an aptamer that can antagonize SEB with nanomolar binding affinity (Kd = 64 nM). The aptamer antagonist ef ...[more]

PMID: 25624325

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