2010 Annual Report 1a.Objectives (from AD-416) To explore the possibility of initial stage of host gene manipulation by developing RNA interference technology using primary lymphocytes. We will use RNAi technology to modulate IFN-y response since IFN-y is a key immunoregulatory cytokine of macrophages for mucosal immune response. 1b.Approach (from AD-416) Peripheral blood monocytes will be cultured in vitro and treated with siRNA using recently developed RNA interference (RNAi) technology to knockdown/silence post-transcriptional gene expression of chicken IFN-y. 3.Progress Report Cell-mediated immune response will was targeted for RNA interference (RNAi) technology to modulate the response of chicken cytokine interferon gamma (IFN-¿), a macrophage-activating factor. IFN-¿ is a key immunoregulatory cytokine of macrophages for mucosal immune response. To do this, peripheral blood monocytes was cultured in vitro and treated with small inhibitory RNA (siRNA) using recently developed RNAi technology to knockdown/silence post-transcriptional gene expression of chicken IFN-¿. Three siRNAs produced fragments indicative of successful cloning and initial results showed partial reduction of IFN-g and IFN-a. Further optimization is being carried out. Progress is monitored by written progress reports, regular teleconferences and meetings.