U937 cells deprived of endogenous annexin 1 demonstrate an increased PLA_2 activity

摘要

Annexin 1(An 1), a phospholipid and calcium binding protein, is strongly expressed in differentiated U 937 cells. in attempting to correlate the expression of An 1 with phospholipase A_2(PLA_2) activity, U937 cells were stably transfected both with a Sense and Antisense cDNA for An 1. PLA_2 activity was Measured by Flow cytometry analysis utilizing the ibs-Bodipy-C_11-PC fluorescent probe. U937 cells stably transfected with the sense or antisense vectors were differentiated for 24 h with Phorbol 12-myristate 13-acetate (PMA, 6 ng ml~-1). Both in undifferentiated and differentiated cells, the Antisense clone(36.4 AS) showed consistently higher PLA_2 activity than the control Sense clone(15 S).