PRIMING EFFECT OF PSEUDOMONAL LEUKOCIDIN ON CHEMILUMINESCENCE RESPONSE OF RABBIT POLYMORPHONUCLEAR LEUKOCYTES

To clarify effects of pseudomonal leukocidin (42.5 kd) on chemilumines cence (CL) production of polymorphonuclear leukocytes (PMNs), rabbit P MNs were stimulated by zymosan or phorbol myristate acetate (PMA) afte r pretreatment with the leukocidin, which by itself stimulated little chemiluminescence response. The extent of CL responses stimulated by z ymosan or PMA was respectively 5.3- or 3.5-fold greater in leukocidin (1.5 mug/ml)-pretreated PMNs than in nonpretreated ones. The priming e ffect of the leukocidin was greater than that of G-CSF and related to some steps before NADPH oxidase activation. The increased CL productio ns might be related to tissue damages caused by pseudomonal infections in vivo.