成纤维母细胞样基质细胞在人工假体无菌性松动中的作用

目的研究成纤维母细胞样基质细胞（FBSCs）在人工关节置换术后无菌性松动中的作用。方法酶消化法从人工假体周围假膜标本中分离FBSCs并作体外培养并加入骨水泥颗粒，检测FBSCs核因子KB受体激动剂配体（RANKL）和肿瘤坏死因子（TNFα）mRNA表达的变化。同时FBSCs与外周血单个核细胞共培养，加入巨噬细胞克隆集落刺激因子、骨保护素或抗TNFα中和抗体；检测破骨细胞的形成并比较其生物学活性。结果假膜组织来源的FBSCs均表达RANKL和TNFamRNA；骨水泥颗粒组FBSCs RANKL和TNFα mRNA的表达量分别是对照组的1．9倍和2．1倍（P=0．002；P=0．004）。共培养细胞培养终末时见到抗酒石酸磷酸酶染色阳性的多核细胞，同时象牙磨片上有虫噬样骨吸收陷窝的形成；OPG完全阻断共培养组抗酒石酸磷酸酶染色阳性多核细胞以及虫噬样骨吸收陷窝的形成，而TNFα中和抗体对上述现象无显著抑制作用。结论骨水泥颗粒显著增强人工假体周围假膜中FBSCs RANKL和TNF mRNA的表达；FBSCs通过表达RANKL而支持外周血单个核细胞分化为具有骨吸收活性的破骨细胞。

Roles of fibroblastic stromal cells in prosthesis aseptic loosening

Objective To study the role of fibroblastic stromal cells in aseptic loosening.Methods Fibroblastic stromal cells were isolated from fresh pseudomembrane from 7 patients undergoing revision ar-throplasty for aseptic loosening of the hip and cultured in the presence and absence of bone cement(PMMA +BaSO_4)particles.Semiquantitive RT-PCR was performed to check the effect of bone cement particles on the expression of RANKL and TNFαmRNA in the stromal cells.The fibroblastic stromal cells were also cocultured with peripheral blood monocytes(PBMCs).At the end of the culture,immunohistochemistry staining was performed to check the expression of tartrate resistant acid phosphatase(TRAP).Resorption lacunae on dentine slices was checked using light microscopy and SEM.Results The expression of RANKL and TNfαmRNA in bone cement particles groups were increased by1.9 folds and 2.1 folds respec-tively(P=0.002,0.004 respectively),compared to the control group.TRAP positive multinuclear cells were formed on cover slips,and resorption lacunae on dentine slices was also found in the coculture group.Conclusion Fibroblastic strornal cells can respond to PMMA+BaSO_4 particles,which leads to increased expression of BANKL and TNFαmRNA.Fibroblastic stromal cells can support osteoclast formation and os-teolysis directly from PBMCs.