Interestingly, Kaparakis et al. reported that Gram-negative
bacteria can deliver peptidoglycan to cytosolic nucleotide-
binding oligomerization domain containing protein 1
(NOD1) in host cells via OMVs. Purified OMVs (containing
peptidoglycan) from H. pylori, P. aeruginosa, and Neisseria
gonorrhea up-regulated NF-κB and NOD1-dependent
responses in vitro. Moreover, OMVs are delivered intragastrically
to mice-induced innate and adaptive immune
responses via NOD1-dependent but TLR-independent
mechanism