Detecting Release of Bacterial dsDNA into the Host Cytosol Using Fluorescence Microscopy

  • Roland Felix Dreier
  • José Carlos Santos
  • Petr BrozEmail author
Part of the Methods in Molecular Biology book series (MIMB, volume 1714)


Recognition of pathogens by the innate immune system relies on germline-encoded pattern recognition receptors (PRRs) that recognize unique microbial molecules, so-called pathogen-associated molecular patterns (PAMPs). Nucleic acids and their derivatives are one of the most important groups of PAMPs, and are recognized by a number of surface-associated as well as cytosolic PRRs. Cyclic GMP-AMP synthase (cGAS) recognizes the presence of pathogen- or host-derived dsDNA in the cytosol and initiates type-I-IFN production. Here, we describe a methodology that allows for evaluating the association of cGAS with released bacterial dsDNA during Francisella novicida infection of macrophages, by fluorescence confocal microscopy. This method can be adapted to the study of cGAS-dependent responses elicited by other intracellular bacterial pathogens and in other cell types.


cGAS dsDNA F. novicida Innate immunity Fluorescence confocal microscopy 



This work was supported by a Career Development Award (CDA00032/2015) from the Human Frontiers Science Program.


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Copyright information

© Springer Science+Business Media LLC 2018

Authors and Affiliations

  • Roland Felix Dreier
    • 1
  • José Carlos Santos
    • 1
  • Petr Broz
    • 1
    Email author
  1. 1.Focal Area Infection Biology, BiozentrumUniversity of BaselBaselSwitzerland

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