Krachler, Anne Marie

Sirisaengtaksin, Natalie

Monteith, Pauline

Paine, C E Timothy

Coates, Christopher J

Lim, Jenson

2021

<p>Adhesins facilitate bacterial colonization and invasion of host tissues and are considered virulence factors, but their impact on immune-mediated damage as a driver of pathogenesis remains unclear. <i>Yersinia pseudotuberculosis</i> encodes for a multivalent adhesion molecule (MAM), a mammalian cell entry (MCE) family protein and adhesin. MAMs are widespread in Gram-negative bacteria and enable enteric bacteria to colonize epithelial tissues. Their role in bacterial interactions with the host innate immune system and contribution to pathogenicity remains unclear. Here, we investigated how<i>Y. pseudotuberculosis</i> MAM contributes to pathogenesis during infection of the <i>Galleria mellonella</i> insect model. We show that <i>Y. pseudotuberculosis</i> MAM is required for efficient bacterial binding and uptake by hemocytes, the host phagocytes. <i>Y. pseudotuberculosis</i> interactions with insect and mammalian phagocytes are determined by bacterial and host factors. Loss of MAM, and deficient microbe–phagocyte interaction, increased pathogenesis in <i>G. mellonella</i>. Diminished phagocyte association also led to increased bacterial clearance. Furthermore, <i>Y. pseudotuberculosis</i> that failed to engage phagocytes hyperactivated humoral immune responses, most notably melanin production. Despite clearing the pathogen, excessive melanization also increased phagocyte death and host mortality. Our findings provide a basis for further studies investigating how microbe- and host-factors integrate to drive pathogenesis in a tractable experimental system.</p>

Virulence, 12(1), p. 638-653

2150-5608

2150-5594

33550901

https://hdl.handle.net/1959.11/38645

en

Landes Bioscience

Attribution 4.0 International

Defective phagocyte association during infection of Galleria mellonella with Yersinia pseudotuberculosis is detrimental to both insect host and microbe

Journal Article

Publication