Antibody‐Based Vascular Targeting: Proteomic Techniques for the Identification and Quantification of Membrane Proteins on Endothelial Cells

A comparison of different biotinylation reagents, tryptic digestion procedures, and mass spectrometric techniques for 2‐D peptide mapping of membrane proteins

“…Furthermore, transmembrane proteins and proteins anchored to the cell membrane comprise more than two-thirds of the known protein targets for drugs [3]. However, due to their limited solubility in water and their relatively low abundance [4], membrane proteins have so far escaped a systematic analysis and quantification in biological systems. Methods for the identification and relative quantification of membrane proteins are likely to have an impact in many areas of biological research, including immunology and pharmaceutical sciences.…”

“…We have established a method, termed "2-D peptide mapping", which allows the selective isolation, separation, relative quantification, and identification of membrane proteins [4,5]. This method is based on the labeling of cell surface proteins with an active ester derivative of biotin, protein capture on streptavidin columns, elution and digestion with trypsin, peptide separation through RP-HPLC, and spotting of chromatographic fractions on MALDI plates.…”