Figure 4
Viral pre-challenge increases the recruitment of neutrophils and ED-1-positive macrophages to the IL-1β-challenged brain. Graphs show numbers of neutrophils (A) and ED-1-positive cells (B) in the ipsilateral and contralateral hemisphere at 12 hours, 3 days and 7 days after the microinjection of IL-1Β, in the presence of intravenous vehicle (solid lines) or AdLuc (5 × 109 CFU - dashed lines). Animals microinjected with vehicle into the brain, in the presence of intravenous AdLuc are shown by dotted line (not visible in (A) due to low constitutive neutrophil numbers). Immuno-positive neutrophils (A - arrowheads) and ED-1-positive macrophages (B - arrows) are shown in brown. Intravenous injections are indicated by italic text. Counterstain is cresyl violet. Scale bar represents 50 μm. Results are expressed as mean ± SEM (n =3). Statistical significance is indicated by **P <0.01, ***P <0.001 respectively. CFU, colony-forming unit.