ELISA was performed using a serial dilution of H3K27me3S28p polyclonal antibody (Cat # PAB14058). The antigen usedwas a peptide containing the histone modifications of interest. By plotting the absorbance against the antibody dilution, the titer of the crude serum was estimated to be 1 : 8,300.
A Dot Blot analysis was performed to test the cross reactivity of H3K27me3S28p polyclonal antibody (Cat # PAB14058) with peptides containing other modifications of histone H3 and H4 and with peptides containing unmodified sequences from histone H3. One hundred to 0.2 pmol of the peptides were spotted on a membrane. The antibody was used at a dilution of 1 : 20,000. Figure shows a high specificity of the crude serum for the peptide containing the modifications of interest.