Osteoblasts MC3T3-E1 Response in 2D and 3D Cell Cultures Models to High Carbon Content CoCr Alloy Particles. Effect of Metallic Particles on Vimentin Expression

The study of the biocompability of the metallic materials is a priority treating to avoid the osteolysis and aseptic loosening of prosthesis. Wear debris is considered one of the main factors responsible for aseptic loosening of orthopedic endoprostheses. We examined the response of mouse osteoblasts MC3T3-E1 to high carbon cobalt-chrome (HCCoCr) particles obtained a) from wear-corrosion assays on a pin-on-disk tribometer using as pair an alumina ball and a disc of a HCCoCr alloy, and b) HCCoCr bulk particles obtained by nitrogen gas atomization from an alloy used in clinic for prostheses application. Mitochondrial activity and lactate dehydrogenase activity assayed in 2D and 3D osteoblasts cell culture models were used to evaluate the cellular response to size, shape, and chemical composition of the metallic particles. 2D cell model was used to study the direct interaction of cells with particles and 3D cell cultures was used to more closely mimic in vivo conditions. The results showed that vimentin was overexpressed in the 2D osteoblasts cultures in presence of metal particles. This might be related to the appearance of pseudotumor in the peri-prosthetic vicinity described in some implanted patients.