Project
306-Kamei-microglia
Title
In vivo imaging of the phagocytic dynamics underlying efficient clearance of adult-born hippocampal granule cells by ramified microglia
Description
The phagocytosis of dead cells by microglia is essential in brain development and homeostasis. However, the mechanism underlying the efficient removal of cell corpses by ramified microglia remains poorly understood. Here, the authors investigated the phagocytosis of dead cells by ramified microglia in the hippocampal dentate gyrus, where adult neurogenesis and homeostatic cell clearance occur. Two-color imaging of microglia and apoptotic newborn neurons revealed two important characteristics. Firstly, frequent environmental surveillance and rapid engulfment reduced the time required for dead cell clearance. The motile microglial processes frequently contacted and enwrapped apoptotic neurons at the protrusion tips and completely digested them within 3–6 h of the initial contact. Secondly, while a single microglial process engaged in phagocytosis, the remaining processes continued environmental surveil- lance and initiated the removal of other dead cells. The simultaneous removal of multiple dead cells increases the clearance capacity of a single microglial cell.
Funding
Japan Agency for Medical Research and Development. Grant Numbers: JP19gm1310003, JP22jm0210097, Ministry of Education, Culture, Sports, Science and Technology. Grant Numbers: 20H00481, 20H05894, 20H05895
Title
Time-lapse in vivo two-photon images of tdTomato-positive newborn neurons and GFP-positive microglia
Description
Time-lapse in vivo two-photon images of tdTomato-positive newborn neurons and GFP-positive microglias. The images show a microglia is engulfing neuron. Chennel1 is microglias, and channel2 is neurons.
Description
CX3CR1^{+/GFP}; Nes-CreER^{T2+/-}; Rosa-CAG-LSL- tdTomato^{+/-} mice, which express GFP in microglia and tdTomato in new-born neurons
Intrinsic variables
Transgenic mouse that expresses GFP in microglia and tdTomato in new-born neurons
Gene ontology: Biological processes
Gene ontology: Cellular components
Gene ontology: Molecular functions
Dimensions
620x544x46x2x26
X scales
0.249 micrometer/pixel
Y scales
0.249 micrometer/pixel
Z scales
1.0 micrometer/slice
T scales
600 second per time interval
Microscopy types
two-photon laser scanning microscopy (FBbi:00000254), time lapse microscopy (
FBbi:00000249)
Detection methods
photomultiplier tube (PMT)
Visualization methods
GFP, tdTomato
Illumination methods
photomultiplier tube (PMT)
Contrast enhancing methods
unprocessed raw data
Resolution enhancing methods
Sample preparation methods
living tissue
Body
A1R MP+ multiphoton microscope (Nikon)
Light source
Spectra-Physics MaiTai Deep See
Objective
Olympus XLPLN25XSVMP
Filter set
525/50, 629/56