ABSTRACT
Background Graves ophthalmopathy is generally considered to be an organ-speeifie autoimmune disease.It was reported that 99Tc-methylenediphosphonate (99Tc-M)P) has therapeutic effect on Graves ophthalmopathy,though the mechanism has not been completely delineated.Objective This study was to explore the effects of 99Tc-MDP on the proliferation of retrooeular fihrohlasts (RFs) hyaluronic acid (HA) synthesis,and the expression rate of human leucocyte antigen-DR (HLA-DR) and intercellular adhesion molecule-1 (ICAM-1) in cultured RFs.Methods Retroocular connective tissue was obtained from 2 eyes with Graves ophthalmopathy during the orbital decompression surgery.RFs were cultured with explant culture method in DMEM medium with 20％fetal bovine serum.The cells of 2-7 generations were used in the study.Interferon γ (IEN-γ),interleukin-1 (IL-1),tumor necrosis factor-α (TNF-α) was added in medium for 72 hours to stimulate the growth of the RFs,and then 10,100 and 1000 mg/L 99Tc-MDP was respectively used to co-culture the cells with IFN-γ,IL-1 or TNF-α.3H-TdR incorporation was used to detect the proliferation of RFs,and synthesis of HA,expression rate of HLA-DR and ICAM-1 in RFs were assayed by radio-immunoassay and flow cytometry,respeetively.Results Cultured cells showed the fibrous shape under the inverted microseope with the positive response for vimentin and absent response for cytokeratine.After addition of TNF-α,IFN-γ and IL-1,the proliferation value of RFs,HA level,the expression rate of HLA-DR and ICMA-1 in RFs was (4918.33±297.91) counts/min,(505.83±41.29)mg/L,(56.88±14.67)％ and (63.57± 14.11)％ respectively,showing significant differenee in comparison with normal control group(P＜0.01).However,after co-culture of ＞100 mg/L 99Tc-MDP with TNF-α,IFN-γ and IL-1,the proliferation value of RFs,HA level,the expressing rates of HLA-DR and ICMA-1 were significantly lower than those in the TNF-α,IFN-γ and IL-1 only culture groups(P＜0.01),but were still higher than those in the normal group.Conclusions 99Tc-MDP can suppress cytonike-induced activation and growth of RFs derived from Graves ophthalmopathy in vitro at a dosedependent manner.
ABSTRACT
Objective To observe the influence of technetium [99Tc] methylenedipho-honate (99Tc-MDP) on osteoclastogenesis induced by receptor activator of NF-κB ligand (RANKL) and macrophage-colony stimulating factor (M-CSF)in peripheral blood mononuclear cells in patients with rheumatoid arthritis, and to study the mechanism of 99Tc-MDP in osteoclast differentiation. Methods The monocytes/macrophages were isolated from peripheral blood in patients with rheumatoid arthri-tis, incubated in RPMI-1640 with receptor activator of NF-κB ligand (RANKL, 25 μg/L), macro-phage-colony stimulating factor (M-CSF, 25μg/L ) and different concentrations of 99Tc-MDP (5, 10, 20,and 50 mg/L) for 4,12, and 20 days. Tartrate resistant acid phosphatase staining was used to observe the formation of osteoclasts. Results After 12 or 16 days culture of peripheral blood mononuclear cells, plenty of large nultinuclear cells could be found on the coverslips. 99Tc-MDP markedly inhibited those changes and the inhibitory effects were increased as the concentration of 99Tc-MDP increased (P<0.05). Conclusion 99Tc-MDP probably has some protective effect on rheumatoid arthritis by inhibiting osteoclast formation.