Given that RACK1 modulates the degradation of several signaling molecules through either the proteasome- or lysosome-dependent pathways [62,63], our previous studies have also disclosed that RACK1 regulates the ubiquitination and stability of histone deacetylase 1 (HDAC1) during cerebellum development and fulminant hepatitis progression [64,65], we therefore asked if RACK1 exerted a similar effect on STAT3 stability in CD4+ T cells. Here, CD4 is linked to Fulminant hepatitis.