Article

Abeta-specific T-cells reverse cognitive decline and synaptic loss in Alzheimer's mice.

Biomedical Sciences, University of California Riverside, 92521-0121, USA.
Neurobiology of Disease (Impact Factor: 5.2). 09/2006; 23(2):351-61. DOI: 10.1016/j.nbd.2006.03.008
Source: PubMed

ABSTRACT Active and passive Abeta immunotherapy provide behavioral benefits in AD transgenic mice, but they can also induce adverse immune over-activation and neuropathological effects. Here, we show that a restricted Abeta-specific immune re-activation can provide cognitive and pathological benefits to APPsw + PS1 transgenic mice for at least 2 1/2 months. A single infusion of Abeta-specific immune cells from Abeta-vaccinated littermates improved performance in cognitively impaired APP + PS1 mice. Recipients had lower levels of soluble Abeta in the hippocampus, less plaque-associated microglia, and more intense synaptophysin immunoreactivity, compared with untreated controls. However, Abeta-specific infusates enriched for Th1 or depleted of CD4(+) T-cells were not effective, nor were ovalbumin-specific infusates. These benefits occurred without global or brain-specific inflammatory responses. Chronically high levels of Abeta can cause immune tolerance, hypo-responsiveness, or anergy to Abeta, but our findings demonstrate that Abeta-specific immune cells can resume endogenous Abeta-lowering processes and may be an effective Abeta therapeutic.

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