Biological response to micron- and nanometer-sized particles known as potential wear products from artificial hip joints: Part II: Reaction of murine macrophages to corundum particles of different size distributions.
Macrophages play a pivotal role in tissue reaction and immune response. They recognize, phagocytose particles and generate cytokines to influence local cellular reactions. Friction and wear of implant components usually generates microparticles (MP) in a size range of 1-10 mum and nanoparticles (NP) in the range of 10-1000 nm. To investigate the possible impact of MP or NP on cellular reactions, we exposed murine macrophages (RAW264.7) to corundum MP and NP. The same mass was used in both NP and MP cell culture solutions, i.e. there were more NP than MP per identical volumes of culture solution. After 4, 24, 48, 72, and 96 h aliquots of cell culture supernatants were tested for different cytokines, growth factors and nitric oxide. Macrophages were stained with MGG (May-Grünwald Giemsa), counted and morphologically characterized by scanning electron microscopy and transmission electron microscopy. Particles were attached to cell surfaces and phagocytosed within cells. Cells stimulated with particles or lipopolysaccharides for positive controls showed surface modifications indicating enhanced function. Although only marginal differences between negative controls and particle-stimulated cells were observed in respect to cytokine production, exposure to corundum particles led to a decrease in the number of vital macrophages and to an increase in the number of giant cells. Corundum NP formed micron-sized aggregates in the cell culture medium and led to the production of more giant cells than MP. Sodiumdodecylsulfate polyacrylamide gel electrophoresis of the cell culture medium with particles proved the adsorption of proteins to particles.
Charité Universitätsmedizin Berlin, Campus B. Franklin, Abt. Experimentelle Zahn-Mund-und Kieferheilkunde, Berlin, Germany.
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I
Kranz
J B
JB
Gonzalez
I
I
Dörfel
M
M
Gemeinert
M
M
Griepentrog
D
D
Klaffke
C
C
Knabe
W
W
Osterle
U
U
Gross
D000327:Adsorption / Q000187:drug effects; D000537:Aluminum Oxide / Q000737:chemistry* / Q000494:pharmacology*; D000818:Animals; D002452:Cell Count; D048430:Cell Shape / Q000187:drug effects; D002470:Cell Survival / Q000187:drug effects; D002478:Cells, Cultured; D004591:Electrophoresis, Polyacrylamide Gel; D004801:Eosine Yellowish-(YS); D016179:Granulocyte Colony-Stimulating Factor / Q000378:metabolism; D006622:Hip Prosthesis; D008264:Macrophages / Q000166:cytology* / Q000187:drug effects* / Q000648:ultrastructure; D008751:Methylene Blue; D051379:Mice; D009573:Nitrites / Q000378:metabolism; D010316:Particle Size; D011208:Powders
C043260:May-Grunwald Giemsa; D009573:Nitrites; D011208:Powders; D016179:Granulocyte Colony-Stimulating Factor; D000537:Aluminum Oxide; D008751:Methylene Blue; D004801:Eosine Yellowish-(YS)