TGF-β1 secretion of ROS-17/2.8 cultures on NiTi implant material

The biocompatibility of an orthopedic implant depends oil the effect of the implant oil bone-forming cells, osteoblasts. Changes ill osteoblastic proliferation, maturation and differentiation are important events in ossification that enable monitoring the effect of the implant. Transforming growth factor-beta (TGF-beta) is known to suppress osteoblast proliferation and, oil the other hand, to induce the maturation and differentiation of osteoblasts. Moreover, osteoblasts produce TGF-beta, which is embedded in the bone matrix and activated by bone-resorbing osteoclasts. TGF-beta inhibits osteoclastic activity. Here, we show for the first time the effect of nickel titanium shape memory metal (NiTi) oil osteoblastic cytokine expression. In this Study, we measured the levels of TGF-beta1 with enzyme-linked immunosorbent assay (ELISA) from a ROS-17/2.8 osteosarcoma cell line cultured on different metal alloy discs. FLISA results were proportioned to total DNA content of the samples. We compared NiTi, to stainless steel (Stst), pure titanium (Ti) and pure nickel (Ni). The TGF-beta1/DNA value ill the NiTi group (0.0007+/-0.0003) was comparable with those seen in the Stst (0.0008+/-0.0001) and Ti (0.0007+/-0.0001) groups. The concentration in the Ni group was lower (0.0006+/-0.0003), though not statistically significantly so. Ill addition, the effect of surface roughness on TGF-beta1 production was studied. We compared three different grades of roughness in three differently hot-rolled alloys: NiTi, hot-rolled at 950degreesC, Ti alloy hot-rolled Lit 850degreesC (TiI) and the same Ti alloy hot-rolled at 1050degreesC (TiII). We found that increasing roughness of the NiTi surface increased the TGF-beta1 concentration. Oil the other hand, all roughness groups of TiII showed low levels of TGF-beta1, while a rough TiI surface induced similar TGF-beta1 expression as rough NiTi. Further, these same measurements made with interleukine 6 (IL-6) were found to be Under the detection limit in these cultures. We conclude that a rough NiTi surface promotes TGF-beta1 expression in ROS-17/2.8 cells. (C) 2002 Elsevier Science Ltd. All rights reserved.