INFLUENCE OF AGE ON OXIDATIVE BURSTS (CHEMILUMINESCENCE) OF POLYMORPHONUCLEAR NEUTROPHIL LEUKOCYTES

The release of reactive oxygen species (ROS) during neutrophil oxidati ve bursts is the last of a sequence of different steps leading to the neutralization of pathogen microorganisms. Using luminol-amplified che miluminescence (LACL), the oxidative burst activity of neutrophils in elderly people (greater than or equal to 75 years) was compared with t hat in younger controls (39 years on average) after activation with bo th particulate (Candida albicans) and soluble (formyl-methionyl-leucyl -phenylalanine; fMLP) stimulants. After Candida stimulation, a reducti on in LACL was observed in the elderly subjects in comparison with the controls, but the difference did not reach statistical significance. After fMLP stimulation, the reduction in LACL was significant, thus su ggesting that the Candida pathway of chemiluminescence production seem s to be less affected than the fMLP pathway. This finding raises quest ions concerning the complex differences in the pathways of cell killin g and ROS generation, and their efficacy in the elderly. Various possi ble explanations are discussed, all of which need further investigatio n.