Aqueous two-phase partitioning for proteomic monitoring of cell surface biomarkers in human peripheral blood mononuclear cells.

For proteomic monitoring of processes such as allergy or inflammation an efficient pre-fractionation strategy is required. We isolated plasma membranes from human peripheral blood mononuclear (PBM) cells by aqueous two-phase partitioning. After 1DE combined with LC-MS/MS, several cell surface marker proteins and in total 60 different plasma membrane proteins (out of 84 identified proteins, i.e., 72%) were detected. Plasma membranes obtained were from only one human donor, the procedure is therefore applicable for individual patient screening.