Chemiluminescent response of polymorphonuclear leukocytes to Streptococcus pneumoniae and Haemophilus influenzae in suspension and adhered to glass

Abstract

We measured the luminol- and lucigenin-enhanced chemiluminescent response of human polymorphonuclear leukocytes (PMN) stimulated by various strains of Streptococus pneumoniae and Haemophilus influenzae. In the absence of opsonin, phagocytosis of either bacterial species elicited good PMN response when the bacteria were adhered to a surface but minimal PMN response when they were in suspension. When 10% pooled human serum was used as a source of opsonin, a moderate to excellent chemiluminescent PMN response was elicited during phagocytosis of opsonized bacteria both in suspension and adhered to a surface. We conclude that opsonin significantly enhances PMN chemiluminescence when a suspension-type assay is used and that opsonin-independent mechanisms play a significant role in the chemiluminescent response of PMN during phagocytosis of adherent bacteria.