#$%^&*AU2015100662A420150611.pdf#####ABSTRACT The present invention provides a compound, Isoliquiritigenin, which could inhibit immunesuppressive effect resulted from direct interaction with IKK-P C46A in vivo and in vitro. Isoliquiritigenin effectively inhibits the immune-suppressive effects through regulation of T lymphocytes by inhibiting T cells proliferation and division, suppressing expression of CD69 and CD 25 as well as up-regulating CD71 in a dose-dependent manner. The present invention also provides a method of screening therapeutic agents for treating autoimmune diseases. 17