AVIDIN ATTACHMENT TO BIOTINYLATED HUMAN NEUTROPHILS INDUCES GENERATION OF SUPEROXIDE ANION

The influence of biotinylation and subsequent attachment of avidin on generation of superoxide anion by human neutrophils was studied. Bioti nylation of human neutrophils with succinimide ester of biotin does no t reduce superoxide generation in response to activation with phorbol myristate acetate (PMA) and formyl peptide (FMLP). Addition of avidin to biotinylated, but not native, leukocytes induces generation of supe roxide anion. The kinetics and level of superoxide generation by bioti nylated neutrophils in response to addition of avidin were quite simil ar to those in response to activation with FMLP. The avidin sugar moie ty and charge were not involved in superoxide generation, since strept avidin was also active. Both avidin- and PMA-induced superoxide genera tion were independent of the extracellular calcium, while FMLP-induced superoxide generation was dependent on the presence of calcium in sol ution. Therefore, interaction of avidin with biotinylated components o f the neutrophil membrane alters functional activity of this cell and might induce 'activation-like' reaction of leukocytes.