Zymography on cerebella of control and BB-94-treated mice infected with meningococci. Mice were infected and treated as described in Figure 1. Animals were perfused with cold PBS, and cerebella were harvested and homogenised. As samples were not collected from dead or unsuccessfully perfused animals, a total of 20 treated mice and 13 control were analysed. Gelatinases in cerebella were enriched by incubation with gelatin-sepharose and subjected to gelatin zymography. A. Densitometry of gelatinolytic activity around 92 kDa and 72 kDa. Lane 1: human MMP-9; lane 2: human MMP-2; lanes 3-5: BB-94-treated mice; lanes 6-7: controls. B. Quantification of MMP-9 gelatinolytic activity. Results are combined from 3 independent experiments. AU, arbitrary units. **p < 0.01.