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Regulated expression of MCP-1 by osteoblastic cells in vitro and in vivo
D.T. Graves1, Y. Jiang2 and A.J. Valente3
1Department of Periodontology and Oral Biology,
2Department of Endodontics, Boston University School of Dental
Medicine, Boston 3Department of Medicine, University of Texas
Health Science Center, San Antonio, Texas, USA
Offprint requests to:
Dr. Dana T. Graves, Department of Periodontology and Oral Biology,
Boston University School of Dental Medicine, Boston, MA 02118,
USA
Summary. Inflammation
is characterized by the recruitment of leukocytes from the vasculature.
Recent studies have implicated chemokines as an important class
of mediators that function principally to stimulate leukocyte
recruitment, and in some cases, leukocyte activity. There are
four defined chemokine subfamilies based on their primary structure,
CXC, CC, C and CX3C. Members of the CC chemokine subfamily, such
as monocyte chemoattractant protein 1 (MCP-1), are chemotactic
for monocytes and other leukocyte subsets. The studies described
below focus on the expression of MCP-1 in vitro and in vivo in
an osseous environment. These studies indicate that MCP-1 is typically
not expressed in normal bone or by normal osteoblasts in vitro.
Upon stimulation by inflammatory mediators, MCP-1 is up-regulated.
This expression is temporally and spatially associated with the
recruitment of monocytes in both osseous inflammation and during
developmentally regulated bone remodelling. Further-more, exogenous
MCP-1 applied to inflamed bone enhances the recruitment of monocytes.
Because monocytes produce factors that influence osseous metabolism,
including but not limited to prostglandins, platelet-derived growth
factor, interleukin-1 or tumor necrosis factor, chemokines that
initiate their recruitment are likely to be highly important.
Histol. Histopathol. 14, 1347-1354 (1999)
Key words: Bone,
Chemokine, Cytokine, Osteoblast, Osteoclast, Review
DOI: 10.14670/HH-14.1347
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