Establishment of a human conjunctival epithelial cell line lacking the functional TACSTD2 gene (an American Ophthalmological Society thesis).

PURPOSE To report the establishment of a human conjunctival epithelial cell line lacking the functional tumor-associated calcium signal transducer 2 (TACSTD2) gene to be used as an in vitro model of gelatinous drop-like corneal dystrophy (GDLD), a rare disease in which the corneal epithelial barrier function is significantly compromized by the loss of function mutation of the TACSTD2 gene. METHODS A small piece of conjunctival tissue was obtained from a GDLD patient. The conjunctival epithelial cells were enzymatically separated and dissociated from the tissue and immortalized by the lentiviral introduction of the SV40 large T antigen and human telomerase reverse transcriptase (hTERT) genes. Population doubling, protein expression, and transepithelial resistance (TER) analyses were performed to assess the appropriateness of the established cell line as an in vitro model for GDLD. RESULTS The life span of the established cell line was found to be significantly elongated compared to nontransfected conjunctival epithelial cells. The SV40 large T antigen and hTERT genes were stably expressed in the established cell line. The protein expression level of the tight junction-related proteins was significantly low compared to the immortalized normal conjunctival epithelial cell line. TER of the established cell line was found to be significantly low compared to the immortalized normal conjunctival epithelial cell line. CONCLUSIONS Our conjunctival epithelial cell line was successfully immortalized and well mimicked several features of GDLD corneas. This cell line may be useful for the elucidation of the pathogenesis of GDLD and for the development of novel treatments for GDLD.