Recombinant E.coli LLO/OVA Induces Murine BMDCs Maturation via TLR4 and NOD1 Receptor and Promotes Specific Cytotoxic T Cell Immunity

ObjectiveTo explore the immune stimulation effect of recombinant E.coli LLO/OVA on mice bone marrow-derived dendritic cells (BMDCs) and T lymphocytes in vitro.MethodsAfter BMDCs stimulated by E.coli LLO/OVA, their Toll-like receptor (TLR) and nucleotide-binding oligomerization domain (NOD) receptor signalling pathway were examined by superarray hybridization; and the priming effect of the vaccine activated BMDCs on CD4+T and CD8+T was determined by [3H]thymidine uptake and ELISA, the tumor cytotoxic effect of activated CD8+T cells was determined by cytotoxic assay.ResultsAfter BMDCs were activated by E. coli LLO/OVA via TLR4, NOD1 receptor and NF-κB signalling pathway, the expression of their surface molecules including MHC class ?, MHC class ?, CD40, CD80 and CD86 significantly up-regulated; the secretion of IL-12 and IFN-γ increased also. The mature BMDCs stimulated the allergic CD4+T and CD8+T cells proliferation and their IL-2 and IFN-γ secretion, and the activated CD8+T cells effectively killed B16-OVA melanoma cells and RMA-S/OVA lymphoma cells in vitro.ConclusionE.coli LLO/OVA is effective in inducing BMDCs maturation via activating TLR4 and NOD1 receptor signalling pathway and promoting specific anti-tumor T cell immunity in vitro.