Evaluation of cellular toxicity in Hep G2 cell and endothelial cells on different medical biopolymer supports

Abstract

Cellular responses to xenobiotic and environmental challenges are often cell cycle dependent and in view of the slow turn over in culture of endothelial cells, characterised by a long G1. In the context of the development of vascular models, a range of polyurethane materials as possible scaffolds and substrata have been evaluated for cell adhesion, proliferation and differentiation on the part of human hepatoma (HepG2) and endothelial cell. The aim of this study was to investigate the effect cell proliferation on toxicological end points. A comparison was made, for in vitro assessment of toxicity, between 12 polyurethanes (PU) [with respect to their cytocompatibility]. In our assessment growing population of cells were randomly grown on the different polyurethanes. Neutral red (NR), methy tetrazolium (MTT), and proliferation assays were used to determine the effect of exposure to test (polymer) and control surfaces. Results showed that there was generally a greater divergence between control and test responses for NR but not for MTT. NR proved more sensitive to extract exposure and this was significantly enhanced at a 1:3 medium ratio, rather than 1:1. For contact materials testing, the MTT response for HepG2 cells showed no correlation between synchronised and non-synchronised populations. Reproducibility and variate correlation was better for NR measures. Conclusion: Reduced surface affinity and growth kinetics on the part of Hep G2 and endothelial cells grown on CarbothaneTM, may be associated with deleterious events characteristic of an inflammatory response. A significant increase in the results was obtained where the cells exposed to some test polymers with cell viability increasing to 120-140% relative to control cell survival. The cell proliferation assay revealed significant differences for some of the test materials for synchronised and nonsynchronised cell populations.