No differences were seen at 24 h between the two mouse strains with regard to meningitis-associated intracranial complications (e.g. blood-brain barrier breakdown, see below), CNS inflammation (as indicated by cellular infiltrate and high levels of IL-1β and G-CSF, Fig. 1A–C) and bacterial outgrowth from the CNS (6.4+/−0.3 log cfu/ml cerebellar lysate in wt mice vs. 6.4+/−0.2 log cfu/ml in Bcl-2 transgenic mice). This evidence concerns the gene IL1B and infectious meningitis.