Studying host-pathogen interactions and innate immunity in Caenorhabditis elegans

Abstract

The genetic analysis of mechanisms of pathogen resistance in the nematode Caenorhabditis elegans has revealed a role for evolutionarily conserved signaling pathways that are required for innate immunity in a wide range of organisms, from worms to mammals. C. elegans represents one of the more simple host organisms in which mechanisms of host defense can be dissected, and the use of C. elegans presents the researcher with a wide array of genetic and genomic tools to probe the host-pathogen interface. The study of host defense mechanisms in C. elegans continues to provide an ancient evolutionary perspective on innate immunity, which may generate insights into the conserved processes in phylogenetically diverse host organisms, including humans.

Fig. 1

Different modes of infection of C. elegans elicit immune responses. Three distinct modes of infection of C. elegans have been described that elicit conserved innate immune signaling pathways. (A) Intestinal infection with a wide range of pathogens involves proliferation of bacteria in the intestinal lumen. (B) The nematophagous fungus Drechmeria initiates infection by attachment to the cuticle with subsequent penetration of the epidermis. (C) The attachment of M. nematophilum to the tail region of C. elegans and subsequent rectal invasion induces a protective swelling response at the site of infection.