ENGULFMENT AND KILLING CAPABILITIES OF NEUTROPHILS AND PHAGOCYTIC SPLENIC FUNCTION IN PERSONS OCCUPATIONALLY EXPOSED TO LEAD

Phagocytosis and intracellular killing of Candida albicans and Candida pseudotropicalis by neutrophils as well as phagocytic splenic functio n from lead-exposed workers were studied. Two species of Candida were used since in individuals with myeloperoxidase deficiency neutrophils are unable to kill C. albicans, whereas C. pseudotropicalis can be eff ectively lysed. Phagocytosis with both antigens and phagocytic splenic function were normal in all the workers studied. However, lytic activ ity towards C. albicans, but not C. pseudotropicalis was impaired. Thi s defect was observed in lead-exposed workers with blood lead levels a nd urinary delta-aminolevulinic acid (ALA-U) concentrations in the ''s afe'' (below 60 ug/dl and 6 mg/l, respectively) and toxic ranges. An i mpaired ability to kill C. albicans suggests that lead exposure may le ad to a myeloperoxidase deficiency. With the exception of blood lead l evels and ALA-U concentrations, there was no correlation between any o f the other parameters examined.