TLR4 and infection: DreddD55 IMD mutant flies infected with Xenorhabdus nematophila and Photorhabdus luminescens nemato-bacterial composites also fail to survive infection compared to Dif1 Toll mutants and wild-type infected flies, albeit the 24 h priming with non-pathogenic E. coli prior to X. nematophila and P. luminescens infection.