WB (peptide competition) analysis of CHO-T cells transfected with an insulin receptor-containing vector and stimulated with 50 nM insulin for 5 minutes (Lane 2-5) using GTX25678 Insulin Receptor beta (phospho Tyr960) antibody prior incubated with the non-phosphorylated peptide corresponding to the phosphopeptide immunogen (Lane 3), a generic phosphotyrosine-containing peptide (Lane 4), or the phosphopeptide immunogen (Lane 5). The data show that only the immunogen phosphopeptide blocks the signal, demonstrating the specificity of the antibody.