NOD2 Signaling Contributes to the Innate Immune Response Against Helper-Dependent Adenovirus Vectors Independently of MyD88 In Vivo

Abstract

We previously demonstrated that Toll-like receptor/myeloid differentiation primary response gene 88 (MyD88) signaling is required for maximal innate and acquired [T helper cell type 1 (Th1)] immune responses following systemic administration of helper-dependent adenoviral vectors (HDAds). However, MyD88-deficient mice injected with HDAdLacZ exhibited only partial reduction of innate immune cytokine expression compared with wild-type mice, suggesting MyD88-independent pathways also respond to HDAds. We now show that NOD2, a nucleotide-binding and oligomerization domain (NOD)-like receptor known to detect muramyl dipeptides in bacterial peptidoglycans, also contributes to innate responses to HDAds, but not to humoral or Th1 immune responses. We established NOD2/MyD88 double-deficient mice that, when challenged with HDAds, showed a significant reduction of the innate response compared with mice deficient for either gene singly, suggesting that NOD2 signaling contributes to the innate response independently of MyD88 signaling following systemic administration of HDAds. In addition, NOD2-deficient mice exhibited significantly higher transgene expression than did wild-type mice at an early time point (before development of an acquired response), but not at a later time point (after development of an acquired response). These results indicate that the intracellular sensor NOD2 is required for innate responses to HDAds and can limit transgene expression during early phases of infection.

Innate immunity to adenovirus: lessons from mice

“…It was also suggested that the cytosolic sensors of the nucleotide-binding and oligomerization domain (NOD) family receptor, NOD2, and a NOD-like (NLR) family receptor, NLRP3, contribute to the detection of HAdv in the cytosol [72,73]. Suzuki et al [72] have shown that the intravenous administration of HAdv-C5-based vector triggered reduced levels of activation of the inflammatory cytokines IL-6, TNF-a, and IL-12p40 and chemokines CCL2 and CCL5 in the livers of Nod2 À/À mice, compared to control wild-type mice, when analyzed 6 h after the intravenous virus administration. Muruve et al [73] have demonstrated that 6 h after intravenous administration of HAdv5based vector, the amounts of inflammatory cytokines IL-1b and IL-6 and chemokines CCL2, CCL4, and CXCL10 were significantly lower in the spleens of Nlr-p3 À/À mice compared to WT mice.…”

Cytokine-Conditioned Dendritic Cells Induce Humoral Tolerance to Protein Therapy in Mice

“…Splenocytes were collected from each group of mice (Suzuki et al, 2011). One million splenocytes were washed with stain buffer and used for immediate ex vivo analysis by flow cytometry.…”

Feasibility of Applying Helper-Dependent Adenoviral Vectors for Cancer Immunotherapy

“…We and another group have reported that NOD2 and NLRP3 recognize Ad vector DNA, likely via the NBD, independent of vector sequences and induce pro-inflammatory cytokines in vivo [39,40]. Our data showed that HDAd injected NOD2 deficient (NOD2 −/− ) mice and infected NOD2 −/− mouse derived embryonic fibroblasts (MEFs) show a significant reduction of inflammatory cytokine expression at both the RNA and protein levels compared to WT mice.…”