GSK3B and infection: Interestingly, the infection of triple transgenic mice with mouse hepatitis virus (MHV) leads to significant increases in GSK3β activity and in the number of cells expressing major histocompatibility complex class II (MHC-II), CD4, and CD8, as well as in levels of proinflammatory cytokines (22), suggesting that different viruses cause different changes in GSK3β activity, but the exact detailed mechanisms still need to be investigated further.