Figure 2: Microglia do not control apoptosis progression.
From: Distinct roles for BAI1 and TIM-4 in the engulfment of dying neurons by microglia
(a) Double staining of PS exposure and chromatin condensation. Neurons exposing PS in grey (NBT::ΔLexPR::secA5-TagBFP) and condensed chromatin in green (Acridine Orange). White arrowheads point to apoptotic neurons that are positive for PS but negative for AO. The yellow arrowhead points to a neuron that is positive for both markers. Top panel-overlay; middle panel—PS-positive neurons; bottom panel—AO-positive neurons. (b) Number of uncollected apoptotic neurons that are positive for PS (blue bar) and for AO (green bar) in 3.5 dpf brains with (+ microglia) and without microglia (− microglia). Quantification has been achieved by examining a ROI (120 × 120 × 80 μm) as shown in d and e. (c–e) Dorsal views of 3.5 dpf larval brains injected with pU1 morpholino to remove microglia. (c) 30 μm confocal stack showing activated Caspase-3 antibody in red. (d) PS-positive neurons in red (NBT::ΔLexPR::secA5-TagBFP). 30 μm stack. (e) Acridine Orange-positive neurons in green. 30 μm stack. The dotted line in d and e represents the ROI used for quantification (120 × 120 × 80 μm). Experiments performed using an Olympus FV 1000 with a × 40/NA 1.15 objective. Scale bar for a, 5 μm; scale bar for c−e, 25 μm. ROI, region of interest.
