EFFECT OF PYRIDOXAL 5'-PHOSPHATE ON HUMAN NEUTROPHIL RESPIRATORY BURST AND ADHESION ON SERUM COATED MICROPLATES

The effect of pyridoxal 5'-phosphate (PP) on human polymorphonuclear l eukocytes respiratory burst and on cellular adhesion on serum coated m icroplates was investigated. No dose-response effect was observed afte r 10 min pre-treatment at 37 degrees C of human neutrophils with incre asing doses of PP, ranging from 0.05 mM/L to 0.5 mM/L. The production of superoxide anion (O-2), after challenging cells with 0.5 pM/L formy l-methyonyl-leucyl-phenylalanine, 50 ng/mL phorbol myristate acetate o r 50 pg/mL concanavalin A was comparable to that observed by pre-treat ing cells with phosphate buffered saline only (control, no PP), theref ore indicating that PP did not affect neutrophil respiratory burst in our assay conditions. Evaluation of the effect on cellular adhesion on to fetal bovine serum pre-coated microplates produced the same results . As previous results showed that PP in the range of 0.01 mM/L to 0.6 mM/L proved to be an efficient inhibitor of neutrophil aggregation, th e evidence reported here might contribute to establish PP as a good in vitro leukocyte anti-aggregant which does not affect other functional parameters. (C) 1998 Elsevier, Paris.