It has recently been reported that alzheimer’s symptoms could be alleviated by transplanting stem cells derived from human umbilical cord, amniotic membrane-derived epithelial cells and mesenchyme into the brains of alzheimer’s transgenic animals. The treatment led to improve cognitive and memory perfomances and increased neuronal survival as a result of the decrease in beta-amyloid, amyloid precursor protein generation, and microglia activation. Another study has reported a therapeutic effect of decreasing the size and number of beta-amyloid  as a result of differentiating peripheral mononuclear cells into microglia by injecting stromal cell-derived factor 1 into alzheimer’s transgenic animals.