Altered oxidative responses and antibacterial activity of adult rabbit alveolar macrophages exposed to poly(methyl methacrylate).

The effect of poly(methyl methacrylate) (PMMA) on the oxidative responses and antibacterial activity of adult rabbit alveolar macrophages (AM) was studied. PMMA beads (ca. 0.3 micron diameter) elicited an acute respiratory burst within 6-8 min after the addition of the beads. In contrast. Teflon beads of comparable size (ca. 0.2 micron diameter) did not elicit an oxidative burst of AM. An oxidative response was elicited only by those PMMA samples that had affinity for AM adherence. Incubation of AM with PMMA beads reduced the subsequent phorbol myristate acetate (PMA)-elicited oxidative burst by more than 80%. The Staphylococcus epidermidis--RP12 killing capacity of AM was greatly increased when PMMA beads (ca. 0.3 micron) were added to the challenge dose of bacteria. Pre-incubation of freshly harvested AM with PMMA beads, which greatly reduced subsequent PMA-elicited chemiluminescent (CL) responses did not significantly affect the RP12 killing capacity of AM. Our data also suggest that killing of the RP12 strain of S. epidermidis does not involve reactive oxygen intermediates.