Intravacuolar persistence in neutrophils facilitates Listeria monocytogenes spread to co-cultured cells

We are proud of Stefano Bagatella’s third first-author PhD manuscript on Listeria monocytogenes (Lm)! We show that neutrophils can harbor inactive but resilient Lm within their vacuoles, with most bacteria entering a viable but non-culturable (VBNC) state. Such persistent bacteria can be transferred from neutrophils to other cells where they reactivate their intracytosolic life cycle and multiply. We therefore uncover neutrophils as potential hosts for VBNC bacteria and as a novel niche for intracellular survival of Lm, which warrants further investigation due to its potential implications for intra-host dissemination, recurrent infections and possible therapeutic pitfalls.