Phosphorothioate CpG oligodeoxynucleotides (ODN) are reported to be recognized by the membrane-bound TLR9 and trigger the MyD88-dependent up-regulation of Type I interferons and pro-inflammatory cytokines. Whether plasmids containing multiple CpG motifs stimulate the same signaling pathway is yet to be determined. The present results show that the CpG motifs enrich plasmid pUC18-CpG stimulates RAW 264.7 in vitro, mainly through the TBK1-mediated signaling pathway, causing the up-regulation of IFN-β, and pro-inflammatory cytokines TNF-α and IL-6. When pUC18-CpG is co-administered with the recombinant Echinococcus granulosus antigen, the antigen-specific antibody titers are markedly increased compared to the Quil-A adju- vanted group. Antigen specific cytokine quantification shows that cytokine profiles from the pUC18-CpG adjuvanted-group are switched to a Th1-biased immune response.
The study was aimed to develop an indirect enzyme-linked immunosorbent assay (ELISA), which can detect specifically Feline herpesvirus type 1 (FHV-1). The primers were designed based on the conserved sequence of FHV-1 glycoprotein B gene. The recombinant protein with reactogenicity was purified as coating antigen of the assay. The indirect ELISA, characterized by high sensitivity showed no cross-reaction with two types of feline virus, had detection limit at 1:2000 dilution. The positive rate of the assay, according to the determined cutoff value (0.25), was basically consistent with Feline Herpes Virus Antibody ELISA kit. In conclusion, the indirect ELISA with high repeatability and reproducibility can be used for detecting FHV-1, and can provide necessary support to related research.