Functional classification and validation of the differentially expressed proteins. The changed proteins identified by LC-CHIP Q-TOF MS/MS for Jurkat (a) and U937 cells (b) were characterized according to their molecular functions by PANTHER Classification System. (c) Jurkat cells were treated with or without 6S (15 μM) for 12 h, and whole-cell lysates were obtained and subjected to western blot analysis using antibodies against Vimentin, DDX1, Cathepsin D and β-actin. Each blot is the representative result of three independent experiments. (d) The comparison of fold changes between proteins identified by mass spectrometry and proteins validated by western blot.