Infection with Angiostrongylus cantonensis reveals up- and down-regulation of the protein profile in the mucus of infected slugs.

Host-parasite adaptation is crucial for evolutionary success of a parasite. The nematode Angiostrongylus cantonensis has a heterogenic life cycle involving molluscs as intermediate hosts and rats as definitive hosts. Several mollusc species are susceptible hosts of A. cantonensis, allowing the development of first-stage larvae (L1) into third-stage larvae (L3). Changes in the metabolism of infected molluscs have been demonstrated, disturbing regular routes and inducing host defence mechanisms. This study aimed to identify changes in the proteomic content of Phyllocaulis spp. mucus during A. cantonensis infection. Proteins were extracted from the mucus samples of infected and non-infected slugs and identified using liquid chromatography-tandem mass spectrometry. We found 26 up-regulated and 15 down-regulated proteins in infected slugs compared to non-infected slugs. Protein profiles are promising markers of parasite infection, and a better understanding of proteomic profiles during infection may help inform in vivo studies and promote new tools for the non-invasive identification of infected hosts.