Identification of Leukemia Surface Proteins Using a Proteomic Technique

ABSTRACT

BACKGROUND: Numerous cell surface proteins of leukemia cells such as CD33 and CD52 have been identified as diagnostic and therapeutic targets. Thus the profiling of the cell surface proteome and proteins restricted to specific leukemia(s) can provide a way to identify novel targets for leukemia diagnosis and therapy. However, there is a lack of data pertaining to the comprehensive analysis of surface membrane proteins because there are few effective strategies for profiling surface membrane proteomes. METHODS: We report on the application of quantitative proteomic techniques that incorporate affinity-capture and purification on monomeric avidin columns to identify all biotinylated cell surface proteins from leukemia cell lines. RESULTS: An analysis of a subset of biotinylated proteins among the different human leukemia cell lines using matrix-assisted laser desorption ionization and tandem mass spectrometry identified, among others, some widely expressed proteins in leukemia cells, such as CD11a, CD11c, CD18, CD31, CD44, and CD147, as well as a set of proteins identified as chaperone proteins, including HSP90, GRP78, GRP75, HSP70, HSP60 and protein disulfide isomerases. On the basis of their known functional roles, several of these proteins may participate in the progression of leukemogenesis and should be considered as potential markers of leukemia. CONCLUSION: Comprehensive profiling of the leukemia cell surface proteome provides an effective approach for the identification of commonly occurring proteins as well as proteins with restricted expression patterns to a specific cell line.