ABSTRACT
Introduction@#The aim of this research project is to elucidate the crosstalk of innate and adaptive immune reactions against the DNA containing bacteria.@*@#This study held in the Core laboratory, Science Technology Center, Mongolian National University of Medical Sciences (MNUMS). Murine aortal endothelial cells, END-D cultured and the cell viability checked by MTT assay. In addition, the NO production, protein and gene expression studied by Griess Reagent assay, R.T-PCR and immunoblotting, respectively. @*Results@#0.1µM, 1µM and 10µM of TLR9 ligand exhibited no cytotoxic action against the cells by MTT assay. IFN-ү alone induced NO production in END-D cells. In the other hand, TLR9 ligand at 0.1µM, 1µM and 10µM up-regulated IFN-ү induced NO production in dose dependent manner. RTPCR results exhibit that TLR9 ligand up regulates iNOS mRNA. Immunoblotting analysis showed the enhanced iNOS protein expression and phosphorylation of STAT1 in cells pre-treated with TLR9 ligand.@*Discussion@#We have demonstrated CpG DNA, TLR9 ligand, up-regulates IFN-ү induced NO via enhanced IFN-ү signaling. The result of Western Blotting and RT-PCR support the up-regulation of NO. CpG DNA can be used as agent against virus and bacteria. Further research need to be conducted. @*Conclusion@#TLR9 ligand, CpG DNA up-regulates IFN-ү induced NO production in time and dose dependent manner. TLR9 ligand augments the expression of iNOS mRNA and STAT1 phosphorylation in response to IFN-ү.