Histone signal is shown relative to the mean of all CpG-island promoters in the same cell type (TSS +/-2.5 kb, four groups pooled; 5,783 genes); the divisors, in signal p-value bigWig units, are H3K4me3: HPC 26.3, T cell 51.2, B cell 35.3; H3K27me3: HPC 2.67, T cell 1.02, B cell 0.943.
