title: Increased T cell recruitment to the CNS after amyloid beta 1-42 immunization in Alzheimer's mice overproducing transforming growth factor-beta 1.
abstract: Immunotherapy targeting the amyloid beta (Abeta) peptide is a novel therapy under investigation for the treatment of Alzheimer's disease (AD). A clinical trial using Abeta(1-42) (AN1792) as the immunogen was halted as a result of development of meningoencephalitis in a small number of patients. The cytokine TGF-beta1 is a key modulator of immune responses that is increased in the brain in AD. We show here that local overexpression of TGF-beta1 in the brain increases both meningeal and parenchymal T lymphocyte number. Furthermore, TGF-beta1 overexpression in a mouse model for AD [amyloid precursor protein (APP) mice] leads to development of additional T cell infiltrates when mice were immunized at a young but not old age with AN1792. Notably, only mice overproducing both Abeta (APP mice) and TGF-beta1 experienced a rise in T lymphocyte number after immunization. One-third of infiltrating T cells were CD4 positive. We did not observe significant differences in B lymphocyte numbers in any of the genotypes or treatment groups. These results demonstrate that TGF-beta1 overproduction in the brain can promote T cell infiltration, in particular after Abeta(1-42) immunization. Likewise, levels of TGF-beta1 or other immune factors in brains of AD patients may influence the response to Abeta(1-42) immunization.
authors.affiliation: Neurology and Neurological Sciences, Stanford University, Stanford, California 94305, USA.
authors.forename: Marion S
authors.initials: MS
authors.lastname: Buckwalter
authors.forename: Bronwen S
authors.initials: BS
authors.lastname: Coleman
authors.forename: Manuel
authors.initials: M
authors.lastname: Buttini
authors.forename: Robin
authors.initials: R
authors.lastname: Barbour
authors.forename: Dale
authors.initials: D
authors.lastname: Schenk
authors.forename: Dora
authors.initials: D
authors.lastname: Games
authors.forename: Peter
authors.initials: P
authors.lastname: Seubert
authors.forename: Tony
authors.initials: T
authors.lastname: Wyss-Coray
mesh_terms: D000544:Alzheimer Disease / Q000276:immunology* / Q000378:metabolism; D023582:Alzheimer Vaccines / Q000008:administration & dosage / Q000276:immunology; D016229:Amyloid beta-Peptides / Q000008:administration & dosage* / Q000276:immunology*; D000818:Animals; D002452:Cell Count / Q000379:methods; D002490:Central Nervous System / Q000276:immunology* / Q000378:metabolism; D008213:Lymphocyte Activation / Q000276:immunology*; D051379:Mice; D008810:Mice, Inbred C57BL; D008822:Mice, Transgenic; D010446:Peptide Fragments / Q000008:administration & dosage* / Q000276:immunology*; D013601:T-Lymphocytes / Q000276:immunology* / Q000378:metabolism; D016212:Transforming Growth Factor beta / Q000096:biosynthesis* / Q000235:genetics / Q000502:physiology; D053773:Transforming Growth Factor beta1
chemical_list: D023582:Alzheimer Vaccines; D016229:Amyloid beta-Peptides; D010446:Peptide Fragments; C508961:Tgfb1 protein, mouse; D016212:Transforming Growth Factor beta; D053773:Transforming Growth Factor beta1; C075222:amyloid beta-protein (1-42)