Luminol-enhanced chemiluminescence of whole blood. Statistical analysis, and comparison of the responses of different subjects.

We studied the effects of different variables on luminol-enhanced chemiluminescence (CL) of whole blood, induced by N-formyl-methionyl-leucyl-phenylalanine (FMLP), opsonized zymosan particles (OZP), or phosphate buffered saline (PBS). Use of correction factor based on blood neutrophil count and hemoglobin concentration decreased interindividual variation and improved normality of the frequency distributions of CL responses. In FMLP- and PBS-induced CL, day-to-day variation was not significant, but it was significant in OZP-induced CL. Although storage of blood samples for 8 hours decreased CL, the decrease was not evident in a study of initial activation, i.e. CL measured at one minute after application of FMLP. Our results suggest that FMLP-induced initial activation is well suited for epidemiological studies because it is easy to determine and is affected neither by day-to-day variation nor by storage of the blood samples for a few hours.