BIOCOMPATIBILITY TEST PROCEDURES FOR MATERIALS EVALUATION INVITRO .2. OBJECTIVE METHODS OF TOXICITY ASSESSMENT

Ten materials were tested using quantitative, objectively graded in vitro biochemical and functional assays employing four cell lines used in previous work and five primary cell types. The biochemical methods (DNA synthesis, protein synthesis, and ATP activity) demonstrated good agreement in toxicity ranking of the materials, regardless of which cell culture was used and, also, the cell cultures responded similarly for each method. Methods that measured functional characteristics of cells (adhesion and phagocytosis) were highly sensitive but had low toxicity ranking agreement and reproducibility. Assays (defined as method and cell culture combinations) using cell lines were more reproducible than assays using primary cell types. Significant differences in sensitivity were noted among the assay system for particular material types.