Figure 9

Immunodepletion of inflammatory monocytes but not neutrophils protects the hippocampus from injury. Theiler's murine encephalomyelitis virus (TMEV)-infected mice were treated with RB6-8C5 to deplete inflammatory monocytes and neutrophils (B, E, H, K), 1A8 to deplete only neutrophils (C, F, I, L), or were treated with vehicle (A, D, G, J). Brain-infiltrating leukocytes (BILs) were collected at 18 hpi and inflammatory monocytes and neutrophils were counted by flow cytometry (A-F). RB6 treatment abrogated most of the inflammatory monocyte (B) and neutrophil response (E). 1A8 treatment abrogated the neutrophil response (F) but not the inflammatory monocyte response (C). Histological analysis of hippocampal injury (G-I) and staining for the neuron-specific marker NeuN (J-L) revealed that depletion of inflammatory monocytes and neutrophils protected the hippocampus (H) and preserved the neurons in CA1 (K) whereas depletion of only neutrophils had no effect on the injury (I, L). Scale bar in L is 500 μm and refers to G-L. M = inflammatory monocyte; N = neutrophil. The flow cytometry results are representative of 10 mice per group. The histological analyses are representative of at least five mice per group.