Rabbit eye irritation caused by wearing toxic contact lenses and their cytotoxicities: In vivo/in vitro correlation study using standard reference materials

Abstract

To clarify the relationship between eye irritancy and cytotoxic potential induced by irritant materials, we made lenses coated with standard reference materials (SRMs) prepared from various amounts of zinc diethyldithiocarbamate (ZDEC) and polyurethane (PU). Zinc diethyldithiocarbamate was classified as a mild irritant by the Draize eye irritation test. When ZDEC-SRM coated contact lenses were applied to rabbit eyes, Draize scores increased in proportion to both the ZDEC and PU concentrations used for coating. Furthermore, correlation with the cytotoxic potential (gamma = -0.93) was better than with lactate dehydrogenase (LDH) activities of tears from rabbit eyes wearing these coated lenses (gamma = 0.78). In conclusion, in vivo eye irritancy induced by wearing lenses could be estimated quantitatively with the cytotoxic potentials using a colony assay. Furthermore, we could compare different sensitivities caused by the same set of SRMs among three different sites of tissue. As a result, the order of sensitivity was eye > muscle >> skin.

Evaluation of cytotoxic potential of cored soft contact lenses with adsorbed active ingredients from over-the-counter eye drops

“…Therefore, when evaluating the cytotoxicity of ophthalmological drugs used in conjunction with soft contact lenses, it is necessary to consider not only the adsorption of active ingredients but also their desorption based on the amount of tear fl uid present on the eyes and the rates of replenishment of tears. In the future, correlation studies will be necessary between the in vivo rabbit eye irritancy test (Tsuchiya et al, 1993) and this new test system for in vitro cytotoxicity of soft contact lenses.…”

Chapter 4: Requirements Concerning Antiseptics for Periorbital, Orbital and Intraorbital Application. 4.2.: Local Tolerance

“…To reduce the number of animals used in the preclinical evaluation of ocular toxicity in the Draize tests, a large number of in vitro tests has been developed [11,69,74] (table 1). The relevance of data obtained in these tests is sometimes challenged because in vitro conditions cannot substitute for the complex physical and molecular interactions of tear film and ocular surface in vivo.…”

Studies on segmented polyetherurethane for biomedical application: Effects of composition and hard-segment content on biocompatibility

“…Many researchers [21][22][23][24][25][26] have performed in vitro toxicity assessment using cell culture method. Cytotoxicity tests also have predicted with considerable accuracy the potential in vivo toxicity of various biomaterials.…”

“…Cytotoxicity tests by an in vitro cell culture method frequently have been adapted to assess the safety of materials. [21][22][23][24][25][26] Once a material has been shown to have no toxic response, a cell seeding test can be performed to evaluate the interaction between living cells and material so that more detailed information can be provided on the material's tissue compatibility. [27][28][29][30][31][32] It is known that, except for endothelial cells, which can be fully compatible with blood in the circulating system, no material can completely prevent platelets from adhering to its surface as it makes contact with blood within the cardiovascular system.…”