The Center for Alternatives to Animal Testing is an academic center affiliated with the Division of Toxicological Sciences in the Department of Environmental Health Sciences of the Johns Hopkins University Bloomberg School of Public Health.

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Research Grants 1999-2000

In Vitro Irritancy Test Using Telomerase Transfected Human Corneal Cells

James V. Jester, PhD
The University of Texas Southwestern, Dallas, Texas

Eye irritation testing is recognized as important in determining the safety of consumer products where manufacture or use may lead to accidental exposure and damage to the eye. Irritancy testing as currently performed, however, requires the use of live animals for which there are no recognized alternative replacement tests. The long-range goal of our work is to first develop and then validate an alternative replacement test using a human tissue culture model that reconstructs the anterior, exposed portion of the human eye. A critical first step will be the generation of extended life-span human cells from the anterior part of the eye or cornea that show structural and functional characteristics similar if not identical to normal cells. To establish these cells we will insert into corneal cells a gene encoding the enzyme telomerase that controls the number of times a cell divides, greatly extending if not indefinitely the life the cell while maintaining the normal cellular characteristics unlike cells that are immortalized using various cancer genes. During

Year One we will clone human corneal epithelial, keratocyte and endothelial extended life-span cell lines following insertion of telomerase and establish the cellular characteristics of each clone. In

Year Two we will establish and characterize various 3-dimensional corneal tissue constructs. In

Year Three, we will evaluate the response of 3-dimensional corneal tissue constructs to irritating materials be measuring the area and depth of injury following exposure to eye irritants producing a range of irritancy from slight to severe.