S100A8 and colitis: No significant differences were detected between Bmal1+/+ controls and Bmal1-/- mutants in the expression of the S100a8 AMP, or the anti-microbial enzyme Lyz1 (Figures 4C, D), although, the expression of S100a8 increased during colitis in both Bmal1+/+ controls and Bmal1-/- mutants.