Evaluation of The Pathogenicity ofListeriaspp. inCaenorhabditis elegans

Abstract

Caenorhabditis has proven to be a useful model for studying host-pathogen interactions as well as the ability of nematodes to serve as vectors for the dispersal of foodborne pathogens. In this study, we evaluated whether C. elegans can serve as a host for Listeria spp. While there was an effect of growth media on C. elegans killing, C. elegans exposed to L. monocytogenes and L. innocua pregrown in Luria-Bertani medium showed reduced survival when compared to nonpathogenic E. coli OP50, while L. seeligeri showed survival similar to E. coli OP50. In a preference assay, C. elegans preferred E. coli over L. monocytogenes and L. innocua, but showed no preference between L. monocytogenes and L. innocua. A gentamicin assay indicated that L. monocytogenes did not persist within the C. elegans intestinal tract. Our findings that L. monocytogenes and L. innocua strains tested have equally deleterious effects on C. elegans and that L. monocytogenes did not establish intestinal infection conflict with other recently published results, which found intestinal infection and killing of C. elegans by L. monocytogenes. Further studies are thus needed to clarify the interactions between L. monocytogenes and C. elegans, including effects of environmental conditions and strain differences on killing and intestinal infection.

Characterisation of InlA truncation in Listeria monocytogenes isolates from farm animals and human cases in the province of Quebec

“…The C elegans model was first proposed in 2006 and confirmed in 2007 (Thomsen and others 2006, Forrester and others 2007) when studies showed that the worm is as sensitive to pathogenic L monocytogenes as humans. But Guha and others questioned the model in 2013 (Guha and others 2013) after failing to obtain loss of viability of worms inoculated by L monocytogenes .…”

Listeria monocytogenes, a down-to-earth pathogen

“…Reports on the role of free living nematodes feeding on bacteria as vectors of dispersion of food-borne pathogens are available in the literature (Anderson et al, 2003, 2006; Caldwell et al, 2003; Gibbs et al, 2005; Thomsen et al, 2006; Forrester et al, 2007; Zhou et al, 2007; Guha et al, 2013). Ceanorhabditis elegans can feed on L. monocytogenes , moreover, in an agar plate assay, presence of live cells in the gut and excrement was confirmed and shedding of the pathogen was evidenced (Anderson et al, 2003, 2006; Caldwell et al, 2003; Guha et al, 2013).…”

“…Interestingly, shedding by Diploscapter sp., a bacteriovorous soil nematode, was observed in soil amended with composted turkey manure (Gibbs et al, 2005). Feeding on L. monocytogenes may have deleterious effects on C. elegans (Forrester et al, 2007) and killing of the nematode was demonstrated experimentally (Thomsen et al, 2006) but others did not report killing (Guha et al, 2013) and this remains an open question.…”

Sublethal injury and virulence changes in Listeria monocytogenes and Listeria innocua treated with antimicrobials carvacrol and citral

“…The nematode C. elegans has been used as a model to describe the virulence of L. monocytogenes and other pathogenic bacteria (Costi et al, 2005;Thomsen et al, 2006;Diard et al, 2007;Jensen et al, 2008a;Forrester et al, 2007).…”

“…Studies have demonstrated that many mammalian pathogenic bacteria and fungi can infect and cause disease in a nonvertebrate host, such as C. elegans. The nematode C. elegans has been used as a model to describe the virulence of Listeria monocytogenes and other pathogenic bacteria (Thomsen et al, 2006;Diard et al, 2007;Jensen et al, 2008a;Forrester et al, 2007). This invertebrate animal model requires simple, inexpensive growth conditions, i.e.…”