title: APOE3, but not APOE4, bone marrow transplantation mitigates behavioral and pathological changes in a mouse model of Alzheimer disease.
abstract: Apolipoprotein E4 (APOE4) genotype is the strongest genetic risk factor for late-onset Alzheimer disease and confers a proinflammatory, neurotoxic phenotype to microglia. Here, we tested the hypothesis that bone marrow cell APOE genotype modulates pathological progression in experimental Alzheimer disease. We performed bone marrow transplants (BMT) from green fluorescent protein-expressing human APOE3/3 or APOE4/4 donor mice into lethally irradiated 5-month-old APPswe/PS1ΔE9 mice. Eight months later, APOE4/4 BMT-recipient APPswe/PS1ΔE9 mice had significantly impaired spatial working memory and increased detergent-soluble and plaque Aβ compared with APOE3/3 BMT-recipient APPswe/PS1ΔE9 mice. BMT-derived microglia engraftment was significantly reduced in APOE4/4 recipients, who also had correspondingly less cerebral apoE. Gene expression analysis in cerebral cortex of APOE3/3 BMT recipients showed reduced expression of tumor necrosis factor-α and macrophage migration inhibitory factor (both neurotoxic cytokines) and elevated immunomodulatory IL-10 expression in APOE3/3 recipients compared with those that received APOE4/4 bone marrow. This was not due to detectable APOE-specific differences in expression of microglial major histocompatibility complex class II, C-C chemokine receptor (CCR) type 1, CCR2, CX3C chemokine receptor 1 (CX3CR1), or C5a anaphylatoxin chemotactic receptor (C5aR). Together, these findings suggest that BMT-derived APOE3-expressing cells are superior to those that express APOE4 in their ability to mitigate the behavioral and neuropathological changes in experimental Alzheimer disease.
authors.affiliation: Department of Pathology, University of Washington, Seattle, Washington, USA.
authors.forename: Yue
authors.initials: Y
authors.lastname: Yang
authors.forename: Eiron
authors.initials: E
authors.lastname: Cudaback
authors.forename: Nikolas L
authors.initials: NL
authors.lastname: Jorstad
authors.forename: Jake F
authors.initials: JF
authors.lastname: Hemingway
authors.forename: Catherine E
authors.initials: CE
authors.lastname: Hagan
authors.forename: Erica J
authors.initials: EJ
authors.lastname: Melief
authors.forename: Xianwu
authors.initials: X
authors.lastname: Li
authors.forename: Tom
authors.initials: T
authors.lastname: Yoo
authors.forename: Shawn B
authors.initials: SB
authors.lastname: Khademi
authors.forename: Kathleen S
authors.initials: KS
authors.lastname: Montine
authors.forename: Thomas J
authors.initials: TJ
authors.lastname: Montine
authors.forename: C Dirk
authors.initials: CD
authors.lastname: Keene
mesh_terms: D000544:Alzheimer Disease / Q000276:immunology / Q000378:metabolism* / Q000473:pathology* / Q000503:physiopathology; D016229:Amyloid beta-Peptides / Q000378:metabolism; D000818:Animals; D000831:Animals, Newborn; D053318:Apolipoprotein E3 / Q000378:metabolism*; D053327:Apolipoprotein E4 / Q000378:metabolism*; D001522:Behavior, Animal; D016026:Bone Marrow Transplantation; D002478:Cells, Cultured; D002678:Chimera / Q000378:metabolism; D004195:Disease Models, Animal; D049452:Green Fluorescent Proteins / Q000378:metabolism; D006185:Habituation, Psychophysiologic; D006410:Hematopoiesis; D006624:Hippocampus / Q000473:pathology; D006801:Humans; D007113:Immunity, Innate; D056747:Immunomodulation / Q000276:immunology; D008570:Memory, Short-Term; D051379:Mice; D008810:Mice, Inbred C57BL; D017628:Microglia / Q000473:pathology; D009000:Monocytes / Q000473:pathology; D010641:Phenotype; D058225:Plaque, Amyloid / Q000378:metabolism / Q000473:pathology
chemical_list: D016229:Amyloid beta-Peptides; D053318:Apolipoprotein E3; D053327:Apolipoprotein E4; D049452:Green Fluorescent Proteins