In AD, intravenous administration of human AD-MSC in mice (2 × 105 or 2 × 106 cells/200 μL normal saline) can alleviate allergic inflammation which includes decreasing the number of degranulated mast cells (MCs), IgE level, amount of histamine released, and prostaglandin E2 level; inhibiting the secretion of pro-inflammatory cytokines and chemokines; increasing the expression of Th1 and Th2 cells; and promoting the expression of regulatory T (Treg) cells (49). The gene discussed is IGHE; the disease is Alzheimer disease.