Interaction of inorganic debris particles with cells

After human umbilical vein endothelial cells (HUVEC) were treated with milled particles simulating debris involved in sandblasting of orthopaedic implants (OI) for 24 h, inflammatory and oxidative stress-related parameters as well as cytotoxic response were monitored. Three different types of particles were used: abrasives [corundum—(Al2O3), used corundum retrieved from removed OI (u. Al2O3), and zirconia/silica composite (ZrO2/SiO2)]. Scanning electron microscopy (SEM) was used for cell morphological changes observation. Inflammatory process was monitored by measuring concentration of Interleukin(IL)-6, IL-1β and Tumour Necrosis Factor(TNF)-α with enzyme-linked immunosorbent assay (ELISA). Oxidative stress was monitored by spectrophotometry assessing activity of cholinesterase (ChE) and glutathione S-transferase (GST) and assessing reactive oxygen species (ROS) as well as lipid droplets (LD) by flow cytometry (FCM). FCM was used also for apoptosis assessment. For treated and untreated cells, the extent of cell detachment from glass discs and the budding of the cell membrane were similar. In cells treated with particles, the concentrations of IL-1β and of IL-6 were higher, indicating inflammatory response of the treated cells. ChE activity increased after cell treatment with u. Al2O3 and ZrO2/SiO2. Increased GST activity was found after cells were treated with ZrO2/SiO2. After cell treatment with u. Al2O3, LD quantity increased and ROS quantity in treated cells was comparable with the one in untreated cells. Cytotoxic effect of the particles was not detected when cells were treated with u. Al2O3. Bioactivity of the tested materials in concentrations added to in vitro cell culture indicates a response of the human body to OI.