How brain immune and support cells influence plaque buildup in a mouse model of Alzheimer's

Fibrillar plaques in the brains of human APP(SW) transgenic mice were reconstructed at different stages of formation and maturation.

• Microglial cells may not participate in the removal and degradation of Abeta but could drive plaque formation and development.
• Fibrillar Abeta deposition at microglial cell surfaces appears to trigger neuron degeneration and the activation of astrocytes and other microglial cells.
• Toxic injury to neurons is indicated by the enlargement of neuronal processes and synapses, along with the accumulation of damaged mitochondria and other cellular debris.
• The separation of amyloid cores from neurons and their degradation by hypertrophic astrocytic processes suggest a defensive response to fibrillar Abeta.
• The growth of plaques, characterized by the recruitment of multiple microglial cells, may be a typical feature of cored plaques in transgenic mice.
• Mouse microglial cells exhibit unique features, such as vacuole clusters that evolve into large vacuoles filled with amorphous material, which are not found in human brain microglia.

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