Open AccessOsteoclast differentiation by human osteoblastic cell line SaOS‐2 primed with bacterial lipid A
Author(s) -
Asai Yasuyuki,
Hirokawa Yoshitaka,
Niwa Kinichiro,
Ogawa Tomohiko
Publication year - 2003
Publication title -
fems immunology & medical microbiology
Language(s) - English
Resource type - Journals
eISSN - 1574-695X
pISSN - 0928-8244
DOI - 10.1016/s0928-8244(03)00111-1
Subject(s) - biology , osteoclast , cd14 , tlr2 , cellular differentiation , toll like receptor , microbiology and biotechnology , peripheral blood mononuclear cell , lipid a , activator (genetics) , cell culture , rankl , cytokine , lipopolysaccharide , receptor , tlr4 , signal transduction , immunology , flow cytometry , innate immune system , biochemistry , in vitro , genetics , gene
We examined the responses of human osteoblastic cell line SaOS‐2 to bacterial lipid A, a bioactive center of lipopolysaccharide, during osteoclast differentiation of human peripheral blood mononuclear cells (PBMC). SaOS‐2 cells expressed mRNA for Toll‐like receptor (TLR) 4, MD‐2, CD14, and myeloid differentiation factor 88, whereas they failed to express mRNA for TLR2. Escherichia coli ‐type synthetic lipid A (compound 506) induced cytokine mRNA expression and nuclear factor (NF)‐κB activation in SaOS‐2 cells. Compound 506 also increased the expression of receptor activator of NF‐κB ligand. Further, cells primed with compound 506 augmented the differentiation of PBMC into osteoclastic cells, and the effect was inhibited by anti‐TLR4 monoclonal antibody. These findings suggest that the TLR signaling cascade in osteoblastic cells is involved in regulating the function of osteoclastogenesis.