Legionella pneumophila inhibits type I interferon signaling to avoid cell-intrinsic host cell defense.

Allen, C. N. S.; Banks, D. A.; Shuster, M.; Vogel, S. N.; O'Connor, T. J.; Briken, V.

doi:10.1101/2022.12.21.521455

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bioRxiv · 10.1101/2022.12.21.521455

Legionella pneumophila inhibits type I interferon signaling to avoid cell-intrinsic host cell defense.

Allen, C. N. S.·Banks, D. A.·Shuster, M.·Vogel, S. N.·O'Connor, T. J.·Briken, V.

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Abstract

The host type I interferon (IFN) response protects against Legionella pneumophila infections. Other bacterial pathogens inhibit type I IFN-mediated cell signaling; however, the interaction between this signaling pathway and L. pneumophila has not been well described. Here, we demonstrate that L. pneumophila inhibits the IFN-{beta} signaling pathway but does not inhibit IFN-{psi}-mediated cell signaling. The addition of IFN-{beta} to L. pneumophila-infected macrophages limited bacterial growth independently of NOS2 and reactive nitrogen species. The type IV secretion system of L. pneumophila is required to inhibit IFN-{beta}-mediated cell signaling. Finally, we show that the inhibition of the IFN-{beta} signaling pathway occurs downstream of STAT1 and STAT2 phosphorylation. In conclusion, our findings describe a novel host cell signaling pathway inhibited by L. pneumophila via its type IV secretion system.

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Allen, C. N. S., Banks, D. A., Shuster, M., Vogel, S. N., O'Connor, T. J., Briken, V.. 2022-12-22. Legionella pneumophila inhibits type I interferon signaling to avoid cell-intrinsic host cell defense.. https://doi.org/10.1101/2022.12.21.521455

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