A NEW FLOW CYTOMETRIC ASSAY FOR THE EVALUATION OF PHAGOCYTOSIS AND THE OXIDATIVE BURST IN WHOLE-BLOOD

Phagocytes play an important role in host defence against microorganis ms and different techniques are needed to evaluate their functional ac tivities. Here we describe a rapid, simple and reliable one step proce dure to measure the phagocytosis rate and oxidative burst activation o f both polymorphonuclear leukocytes (PMN) and monocytes, by means of f low cytometry using only small quantities of whole blood. The two spec ies of bacteria employed as test microorganisms, Staphylococcus aureus and Candida albicans showed a somewhat different behaviour. We found that the present method could be used as an alternative test in the di agnosis of chronic granulomatous disease (CGD). Moreover we were able to analyse, in a one step procedure, defective phagocyte functions in a group of paediatric patients suffering from recurrent microbial infe ctions.