Review

Clearance of amyloid-β peptides by microglia and macrophages: the issue of what, when and where

Department of Laboratory Medicine & Pathobiology, University of Toronto, 1 King’s College Circle, Toronto, ON, CA M5S 1A2, Canada

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JoAnne McLaurin

* Author for correspondence

Department of Laboratory Medicine & Pathobiology, University of Toronto, 1 King’s College Circle, Toronto, ON, CA M5S 1A2, Canada.

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Email the corresponding author at j.mclaurin@utoronto.ca

Published Online:8 Mar 2012https://doi.org/10.2217/fnl.12.6

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Abstract

Accumulation of senile plaques consisting of amyloid-β peptide (Aβ) aggregates is a prominent pathological feature in Alzheimer’s disease. Effective clearance of Aβ from the brain parenchyma is thought to regulate the development and progression of the disease. Macrophages in the brain play an important role in Aβ clearance by a variety of phagocytic and digestive mechanisms. Subpopulations of macrophages are heterogeneous such that resident microglia in the parenchyma, blood macrophages infiltrating from the periphery and perivascular macrophages residing along cerebral vessels make functionally distinct contributions to Aβ clearance. Despite phenotypic similarities between the different macrophage subsets, a series of in vivo models have been derived to differentiate their relative impacts on Aβ dynamics as well as the molecular mechanisms underlying their activities. This review discusses the key findings from these models and recent research efforts to selectively enhance macrophage clearance of Aβ.

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Papers of special note have been highlighted as: ▪▪ of considerable interest

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Vol. 7, No. 2

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Published online 8 March 2012

Published in print March 2012

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Financial & competing interests disclosure

The authors received funding support from the Canadian Institutes of Health Research (J McLaurin:PRG 37857), NSERC (CHRP:365537) and the Ontario Postdoctoral Scholarship (AY Lai). J McLaurin consulted for Elan Pharmaceuticals. The authors have no other relevant affiliations or financial involvement with any organization or entity with a financial interest in or financial conflict with the subject matter or materials discussed in the manuscript apart from those disclosed.

No writing assistance was utilized in the production of this manuscript.

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