WB (peptide competition) analysis of HeLa cells treated with TNF-alpha (Lane 2-5) using GTX12865 RPS6 (phospho Ser244/247) antibody prior incubated with the non-phosphopeptide corresponding to the immunogen (Lane 3), a generic phosphoserine-containing peptide (Lane 4), or, the phosphopeptide immunogen (Lane 5) control. The data show that only the immunogen phosphopeptide blocks the signal, demonstrating the specificity of the antibody.