IL1B and brain inflammatory disease: In the absence of an inflammatory challenge, 11β-HSD1 deficiency had no effect on markers of peripheral or brain inflammation, with undetectable Tnfa, Il1b and Il6 mRNA in the hippocampus of Hsd11b1Del/Del and C57BL/6 control mice and no difference in circulating neutrophil and monocyte numbers between genotypes (Supplementary Fig. 4A–C).