CSF1 and colitis: Although the loss of F4/80+ cells suggested a reduction in macrophages, it may also reflect reduced expression of the F4/80 antigen as CSF-1 is reported to induce F4/80 protein expression.[29] To examine further the impact of JNJ-40346527 on the phenotypic composition of mucosal macrophages and to confirm the impact on T cell activation contributing to colitis, we employed further gene set analyses.