Legionella pp 221-238 | Cite as

Perturbation of Legionella Cell Infection by RNA Interference

  • Bernhard Steiner
  • A. Leoni Swart
  • Hubert HilbiEmail author
Part of the Methods in Molecular Biology book series (MIMB, volume 1921)


Legionella pneumophila is a facultative intracellular bacterium, which grows in amoebae as well as in macrophages and epithelial cells. Depletion of genes of interest by RNA interference (RNAi) has proven to be a robust and economic technique to study L. pneumophila-host cell interactions. Predesigned and often validated double-stranded (ds) RNA oligonucleotides that silence specific genes are commercially available. RNAi results in a reduced level of distinct proteins, which allows studying the specific role of host cell components involved in L. pneumophila infection. Here, we describe how to assess RNAi-mediated protein depletion efficiency and cytotoxic effects in human A549 lung epithelial cells and murine RAW 264.7 macrophages. Moreover, we demonstrate how RNAi can be used to screen for novel host cell proteins involved in the formation of the Legionella-containing vacuole and intracellular replication of the pathogen.

Key words

Atlastin Host-pathogen interactions Intracellular bacteria Large GTPase Legionella pneumophila Macrophage Epithelial cells Pathogen vacuole Type IV secretion RNA interference 



N-(2-acetamido)-2-aminoethanesulfonic acid


Argonaute protein


ADP-ribosylation factor 1




Green fluorescent protein


Heat shock protein 90


Intracellular multiplication/defective organelle trafficking


Legionella-containing vacuole


Multiplicity of infection


Propidium iodide


RNA-induced silencing complex


RNA interference


Small interfering RNA


Single-stranded/double-stranded RNA


Type IV secretion system



We would like to thank Stephen Weber and Daniel Strebinger for providing critical input on the manuscript. Work in the group of H.H. was supported by the Swiss National Science Foundation (SNF; 31003A_153200), the Novartis Foundation for Medical-Biological Research, and the OPO Foundation.


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Copyright information

© Springer Science+Business Media, LLC, part of Springer Nature 2019

Authors and Affiliations

  • Bernhard Steiner
    • 1
  • A. Leoni Swart
    • 1
  • Hubert Hilbi
    • 1
    Email author
  1. 1.Institute of Medical MicrobiologyUniversity of ZürichZürichSwitzerland

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