Life Science Seminar

 

▶Subject : Immunological strategies for treating chronic viral infections

▶Speaker : Hyun-Tak Jin (Emory University School of Midicine)

▶Date : 2:00PM / July 25 (Mon) / 2011

▶Place : 1st Floor, Conference Room
 
*Abstract
During chronic viral infections, virus-specific CD8 T cells become unresponsive to viral antigens and persist in a nonfunctional exhausted state. Exhausted CD8 T cells are characterized by step-wise impairment of effector function to produce immune-stimulatory cytokines, lyse virally infected cells, and proliferate. Since CD8 T-cell exhaustion was characterized in the murine lymphocyte choriomeningitis virus (LCMV), such a functional impairment has been a common feature in human chronic viral infections such as human immunodeficiency virus (HIV), hepatitis B virus (HBV), and hepatitis C virus (HCV). Programmed death 1 (PD-1), an inhibitory receptor of the CD28 superfamily, was shown to be highly expressed on exhausted CD8 T cells and play a major role in regulating T-cell exhaustion during chronic LCMV infection. Subsequently, involvement of PD-1 pathway has also been shown in various chronic viral infections including HIV, HBV, and HCV in human, and during simian immunodeficiency virus infection in nonhuman primate. Therefore, targeting the PD-1/PD-1 ligand (PD-L) inhibitory pathway represents an attractive therapeutic strategy to enhance anti-viral immunity and reduce viral reservoirs during chronic infections. However, blockade of PD-1/PD-L pathway does not completely restore T-cell function, indicating the involvement of more complex pathway for regulating T-cell exhaustion. In this context, I will introduce our current studies on immunological strategies for treating chronic infections, which is based on the blockade of PD-1/PD-L pathway in combination with other immune modulators for more effectively boosting anti-viral activity.

☎ Inquiry : Prof. Young Chul Sung(279-2294)