Astrocytic loss in neonatal inflammation is preceded by proliferation/migration of CX3CR1+ cells in the pons. Brain cryosections of C57BL/6 CX3CR1gfp/+ mice at day 6 post-lipopolysaccharide (LPS) administration were immunolabeled for astrocytes (glial fibrillary acidic protein, GFAP, red) and brain microvascular endothelial cells (cluster of differentiation, CD31, gray). Representative confocal images of each condition in the pons are depicted in (A). (B,C) Area fraction per field of GFAP and CX3CR1 (green) positive staining, along with their respective colocalization with vessels, were determined using ImageJ software (NIH, USA). Representative confocal images of sections immunolabeled for astrocytes (GFAP, red) and for ApopTag (gray) are depicted in (D). Quantification of ApopTag+ staining area fraction, using the abovementioned software, is shown in (E). Results are mean ± SEM from at least four animals. **P < 0.01 vs. without (W/O) LPS; §
P < 0.05 and §§
P < 0.01 vs. day 5 post-LPS.