Correlation between measurements of the luminol-dependent chemiluminescence response and bacterial susceptibility to phagocytosis.

The generation of chemiluminescence by phagocytosing leukocytes has been suggested to reflect concomitant microbicidal activity. Correlation between measurements of the chemiluminescence response and susceptibility of bacteria to phagocytosis, however, has not been studied. To examine and compare a range of responses in the two assays, four Escherichia coli serotypes were chosen as test organisms with degrees of susceptibilities to phagocytosis ranging from 0 to 100% bacteria killed. No complete correlation between peak, slope, or curve area integral measurements of the chemiluminescence response and bacterial susceptibility to phagocytosis were found, although a correlation between the two assays could be made after using specific opsonization procedures like the addition of antiserum to selected serotypes. Intrinsic differences present among the bacterial serotypes may be responsible for the observed lack of correlation between the two assays.