MAPT and Alzheimer disease: The extent of tau phosphorylation at multiple epitopes, including Thr181 (pT181), Thr231 (pT231) and pS396, was increased in AD mice underwent splenectomy compared with sham mice, whereas no difference was observed in the levels of total tau (defined as tau5) between the two groups (t = 2.24, p = 0.042 for pT181; t = 2.88, p = 0.012 for pT231; t = 2.64, p = 0.020 for PS396; t = 0.29, p = 0.77 for Tau5; Figure 5d).