sodium-dodecyl-sulfate and Corneal-Opacity

Human corneal equivalents comprising the three main layers of the cornea (epithelium, stroma, and endothelium) were constructed. Each cellular layer was fabricated from immortalized human corneal cells that were screened for use on the basis of morphological, biochemical, and electrophysiological similarity to their natural counterparts. The resulting corneal equivalents mimicked human corneas in key physical and physiological functions, including morphology, biochemical marker expression, transparency, ion and fluid transport, and gene expression. Morphological and functional equivalents to human corneas that can be produced in vitro have immediate applications in toxicity and drug efficacy testing, and form the basis for future development of implantable tissues.

Topics: Animal Testing Alternatives; Biomedical Engineering; Cell Line; Cells, Cultured; Chondroitin Sulfates; Collagen; Cornea; Corneal Opacity; Corneal Stroma; Corneal Transplantation; Cross-Linking Reagents; Culture Techniques; Electrophysiology; Endothelium, Corneal; Epithelium, Corneal; Gene Expression; Glutaral; Humans; Ion Channels; Ouabain; Patch-Clamp Techniques; Sodium Dodecyl Sulfate

Incubation of isolated bovine cornea with the surfactants lauryl trimethylammonium bromide (LTAB), sodium lauryl sulphate (NaLS) or Tween 20 in contact only with the epithelium side (outside) of the cornea produced dose-related development of opacity. The order of efficacy was LTAB greater than NaLS greater than Tween 20. After incubation and opacity reading the epithelium was surgically removed and the opacity of the remaining de-epithelialized cornea (stroma and endothelium) measured. The results indicate that the surfactants caused opacity predominantly by affecting the epithelium which itself became opaque.

Topics: Animals; Cattle; Corneal Opacity; Epithelium; In Vitro Techniques; Polysorbates; Quaternary Ammonium Compounds; Sodium Dodecyl Sulfate

Several concentrations of sodium lauryl sulphate (NaLS) were applied to bovine corneas which were either intact or had the epithelium or endothelium or both removed. The opacities which developed in the corneas were in the order epithelium and endothelium removed greater than endothelium removed greater than epithelium removed greater than intact. Opacities increased with increasing concentrations of NaLS from 5 X 10(-4) M to 5 X 10(-2) M, but at 5 X 10(-1) M all corneal preparations showed a decrease in opacity. It is suggested that the opacity may be due to a reaction between NaLS and stromal proteins.

Topics: Animals; Cattle; Corneal Opacity; Endothelium; Epithelium; In Vitro Techniques; Sodium Dodecyl Sulfate

The in vitro development of bovine corneal opacity induced by two anionic surfactants, sodium decyl sulphate (NaDS) and sodium lauryl sulphate (NaLS), was monitored using a simple, specially constructed instrument, the opacitometer. Results show clearly that NaDS was more potent, and acted more rapidly, than NaLS, an order of potency which has been shown by in vivo ocular irritancy tests with these agents but not in cytotoxicity tests. The measurement of irritant-induced opacity of bovine isolated cornea may therefore offer another approach to the search for viable in vitro alternatives to in vivo ocular irritancy testing.

Topics: Animals; Cattle; Cornea; Corneal Opacity; Dose-Response Relationship, Drug; In Vitro Techniques; Methods; Sodium Dodecyl Sulfate