ISSN:
0021-9304
Keywords:
Chemistry
;
Polymer and Materials Science
Source:
Wiley InterScience Backfile Collection 1832-2000
Topics:
Medicine
,
Technology
Notes:
This study investigated effects of different sizes, concentrations, volumes, and surface areas of polymethylmethacrylate (PMMA) particles on human macrophages. Adherent peripheral blood monocytes isolated from five healthy individuals were exposed for 48 h to phagocytosable (0.325 μm and 5.5 μm) and nonphagocytosable (200 μm) spherical particles. Each particle size was tested over a range of concentrations (104-1011 particles per milliliter [0.325 μm], 102-107 particles per milliliter [5.5 μm], 101-104 particles per milliliter [200 μm]) to provide overlap in number, volume, and surface area. Primary human monocyte/macrophages were cultured in macrophage serum-free medium and 5% fetal calf serum. Macrophage viability was assessed by 3H-thymidine uptake and activation was quantified by release of interleukin-1β, interleukin-6, tumor necrosis factor-α, prostaglandin E2 (PGE2), and the lysosomal enzyme hexosaminidase. Medium alone served as a negative control; lipopolysaccharide (10 μg/mL) was also tested. PMMA particles were not toxic to human macrophages at any concentration tested. The smallest phagocytosable particles (0.325 μm) stimulated the release of interleukin-1β, interleukin-6, prostaglandin E2, and hexosaminidase at concentrations of 1010-1011 particles/mL. The release of cytokines, PGE2, and hexosaminidase depended on the size, concentration, surface area, and volume of the phagocytosable particles. This study demonstrates that PMMA particle load Mi.e., the concentration of phagocytosable particles per tissue volume, characterized by size, surface area, and volume, rather than simply particle number - determines the degree of macrophage activation. © 1996 John Wiley & Sons, Inc.
Additional Material:
8 Ill.
Type of Medium:
Electronic Resource
