Focusing first on the target phosphorylated ZAP-70 peptides, the measured abundances of YpY and pYY in the pre-enrichment fractions agreed with the WB results. Thus, the YpY/pYY intensity ratio was significantly higher in the anti-CD3 (Fig. ) compared to the anti-CD3/H2O2 stimulated cell lysate (Fig. ) whereas the pYpY signal intensity was lower and the YY remained unchanged. Turning to the enrichment results we were pleased to see that the MIP specificity remained intact also in this native sample (Fig. ). Hence, all target peptides were cleanly eluted with a near quantitative recovery and with intensity ratios mirroring the WB and MS/MS results, the latter appearing clearly when scrutinizing the relative abundancy graphs in Fig. . All in all, these data shows that phosphopeptide specific MIPs are compatible with direct target enrichment from lysate digests and that enrichment specificities can exceed those of antibodies.