Unformatted text preview: e also demonstrated the expression of IL-6 and TNF-α in protein and mRNA levels.
MMPs are known to degrade the extracellular bone
matrix, and several types have been shown in loosened
hips.9,21,24,26 We detected the expression of MMP-13
mRNA, which is known to degrade interstitial collagens, especially of the bone and cartilage matrix. Recently, it was reported that polymethylmethacrylate
(PMMA) particles stimulate bone marrow cells to secrete ODF, which induces osteoclast genesis in vitro
and is inhibited by OPG.3 Consistent with this, we demonstrated mRNA expression for ODF and OPG in
the sample. Thus, many cytokines related to bone
resorption were expressed in the retrieved tissue. Neale
et al.22 have shown that IL-6 released by periprosthetic
tissues plays important roles in the early stages of osteoclast formation from mononuclear precursors. On the
other hand, osteoblasts are known to produce IL-6 in
response to polyethylene particles,28 PMMA,30 or titanium particles.27 However, several factors such as particles, cells, and cytokines in...
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- Spring '08
- Hip replacement, ET AL, osteolysis, granulation tissue, polyethylene particles