THE EFFECT OF METAL-IONS ON NEUTROPHIL DEGRANULATION

This study examined neutrophil activation, after incubation of these cells with metal ions. Activation was examined using lysozyme and chemiluminescence assays, Cobalt ions (0.5-30 p.p.m.), chromium ions (0.5-20 p.p.m.), nickel ions (1-50 p.p.m.) and aluminium ions (0.05-7.5 p.p.m.) did not stimulate neutrophils to release lysozyme and did not stimulate a respiratory burst. Copper ions (0.25-7.5 p.p.m.) stimulated neutrophils to release lysozyme, a result which was significant at the 5% level. This was not as a result of copper ions causing neutrophils to lyse. Lysozyme secretion was inhibited when neutrophils were pre-incubated with cytochalasin B, although cytochalasin B had no effect on the enzyme secretion due to stimulation by opsonized zymosan and zymosan-activated serum. This suggests that the mechanism by which copper ions stimulate neutrophil degranulation is different from that of opsonized zymosan and zymosan-activated serum. Enzyme secretion was not accompanied by a respiratory burst.