摘要OBJECTIVE To investigate the effect and mechanisms of Liuwei Dihuang Decoction (LW)on cognition in PrP-hAβPPswe/PS1ΔE9(APP/PS1)transgenic mice.METHODS LW was adminis-trated with oral for 3 months.The locomotor activity test was performed to investigate the spontaneous motor activity of mice. The Morris water maze test and shuttle box test were performed to investigate the spatial learning and memory and active avoidance response respectively.The Αβ deposits and neuron loss in the hippocampus was detected by immunofluorescence staining and nissl staining respectively. The flow cytometry was employed to investigate the lymphocyte subsets of the mice.The 3H-thymidine incorporation was performed to investigate the splenocytes proliferation. RESULTS The treatment of LW ameliorated the impairments of spatial learning and memory and active and passive avoidance in APP/PS1 mice. The administration of LW alleviated neuron loss in the brain, suppressed amyloid-β (Αβ) deposits in the hippocampus of APP/PS1 mice. The treatment of LW significantly increased ConA-and LPS-induced proliferation of splenocytes,increased CD3+T cells and CD19+B cells in the spleen lymphocytes and reduced Gr1+cells in APP/PS1 mice.CONCLUSION This data indicated the adminis-tration of LW ameliorated behavioral and pathological deterioration via regulating immune function.