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bioRxiv · 10.1101/305847

Staphylococcal superantigen-like protein 13 activates neutrophils via Formyl Peptide Receptor 2

Zhao, Y.·van Kessel, K. P. M.·de Haas, C. J. C.·Rogers, M. R. C.·van Strijp, J.·Haas, P.-J.
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Abstract

Staphylococcal Superantigen-Like (SSL) proteins, one of major virulence factor families produced by Staphylococcus aureus, were previously demonstrated to be immune evasion molecules that interfere with a variety of innate immune defenses. However, in contrast to these characterized SSLs, that inhibit immune functions, we show that SSL13 is a strong activator of neutrophils via the formyl-peptide receptor 2 (FPR2). Moreover, our data show that SSL13 acts as a chemoattractant, induces degranulation and oxidative burst in neutrophils. As with many other staphylococcal immune evasion proteins, SSL13 shows a high degree of human specificity. SSL13 is not able to efficiently activate mouse neutrophils, hampering in vivo experiments.\n\nIn conclusion, SSL13 is a neutrophil chemoattractant and activator that acts via the FPR2. Therefore, SSL13 is a unique SSL member that does not belong to the immune evasion class, but is a pathogen alarming molecule.

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Zhao, Y., van Kessel, K. P. M., de Haas, C. J. C., Rogers, M. R. C., van Strijp, J., Haas, P.-J.. 2018-04-21. Staphylococcal superantigen-like protein 13 activates neutrophils via Formyl Peptide Receptor 2. https://doi.org/10.1101/305847

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