Quantitative assessment of human neutrophil chemiluminescence induced by opsonized Escherichia coli K-12

Abstract

The interaction of opsonized E. coli K-12 bacteria and polymorphonuclear leukocytes (PMN) was quantified, using luminol-enhanced chemiluminescence (CL) as a parameter of PMN stimulation. On a double-logarithmic scale light emission depended on the opsonin concentration used during pre-opsonisation. The most potent CL-inducing agent was fresh human serum, and its stimulatory activity depended on an intact complement (C) system. Both inactivation of C by heating or blocking the classical C pathway with EGTD decreased the CL-inducing potency by a factor of 8 to 16. Hypogammaglobulinemic heated serum mediated little CL. IgG for intravenous use mediated CL generation, but reduction/alkylation and sulphitolysis reduced the stimulatory power. Evidence is presented that the anti-K-12 antibodies within commercial IgG and IgM used for substitution do not improve the stimulatory power of IgG-deficient, IgM- and C-sufficient serum, unless very high Ig concentrations are substituted.