Established cell lines and primary cultures in testing medical devices in vitro

In testing for the cytotoxicity of medical devices, crucial parameters are the type of cells, the duration of the exposure, the physical form of the d evice and the method of evaluation. Using cell cultures the changes of cell functions induced by artificial materials may be evaluated. In screening r ests the effect of biomaterials on functions common to all cell types is in vestigated through both continuous lines and primary cultures. In supplemen tary tests the effect of biomaterials on specific functions is studied, emp loying cells of the same type of those which will be in contact with the de vice in vivo. Osteoblasts, either From primary culture or an established li ne, are used to study the interaction with materials for bone implants. We evaluated whether dental cements affect the replication cycle of osteoblast -like cells MG63. The S phase was inhibited by the cements with a phenolic group, even though to a different extent. Mononuclear cell cultures are use d to investigate the immune response, which is important in the host reacti on to implant. We investigated whether the chromium ions released in a biol ogical fluid may induce PBMC to produce cytokines involved in bone resorpti on. Chromium extract did not impair TNF alpha release significantly, but in hibited IL-6 release significantly in stimulated PBMC. Endothelial cell cul tures are useful to the evaluation of materials for vascular grafts. We stu died the influence of some types of Dacron on endothelial functions. Collag en-coated Dacron decreased significantly the production of 6-keto-prostagla ndin F-1 alpha. Knitted Dacron caused a significant increase of tissue fact or, a significant reduction in PECAM-1 and a significant increase in ELAM-1 . (C) 1999 Elsevier Science Ltd. All rights reserved.