Microglia are primary immune cells of the CNS. Resting microglia found in the healthy adult brain play a critical role in defending its structural and functional integrity. An appearance of a pathological agent/event elicits rapid activation of these cells. Microglial activation also accompanies normal aging as well as neurodegenerative diseases like Altheimer’s disease (AD). In AD brains microglia are clustered in and around amyloid β deposits, the main histological hallmark of the disease.

The properties of microglia were extensively studied in reduced preparations (cell cultures) but little is known about functional properties of these cells in vivo. By using multicolor high-resolution two-photon imaging combined with different cell labeling techniques we aim at understanding the mechanisms underlying in vivo calcium signaling in microglia (see also Novel microglial calcium signal is a rapid sensor of neuronal damage in vivo) as well as their morphological responses to physiological stimuli in the aging and diseased brain. The ultimate goal of our work is to understand the contribution of microglia to the development of AD and thus to identify possible new strategies for AD therapy.