TY - JOUR T1 - Safety profile of accelerated corneal cross-linking versus conventional cross-linking: a comparative study on ex vivo-cultured limbal epithelial cells JF - British Journal of Ophthalmology JO - Br J Ophthalmol SP - 272 LP - 280 DO - 10.1136/bjophthalmol-2014-305495 VL - 99 IS - 2 AU - Rohit Shetty AU - Himanshu Matalia AU - Rudy Nuijts AU - Murali Subramani AU - Kamesh Dhamodaran AU - Ramanan Pandian AU - Chaitra Jayadev AU - Debashish Das Y1 - 2015/02/01 UR - http://bjo.bmj.com/content/99/2/272.abstract N2 - Aim/background To compare the effects of accelerated corneal collagen cross-linking (ACXL) and corneal collagen cross-linking (CXL) on ex vivo-cultured limbal epithelial cells (LECs). Methods Day 14 cultured LECs were either unexposed (control) or exposed to different intensities of ultraviolet-A (UV-A) irradiance for different durations (3 mW for 30 min, 9 mW for 10 min, 18 mW for 5 min and 30 mW for 3 min) in the presence and absence of riboflavin. These cells were further processed for quantitative real-time PCR, vital staining, immunofluorescence staining and fluorescence-activated cell sorting (FACS) staining to evaluate the apoptotic status. Statistical analysis was performed using a Student t test. Results Vital staining showed a significantly higher (p=0.004) dead cell population with 3 mW for 30 min when compared with 30 mW for 3 min exposure (p=0.225). Quantitative PCR results revealed significantly reduced abcg2 and Δnp63 mRNA levels, while FACS analysis showed an increase in ABCG2-Annexin V positive population in cells exposed to 3 mW for 30 mins. Neither reduction of mRNA expression of abcg2 and Δnp63 nor increase in FACS-stained ABCG2-Annexin V positivity was detected in cells exposed to 30 mW for 3 min. Additionally, enhanced caspase activity was detected with fluorochrome inhibitor of caspases staining and mRNA expression of caspase 3 and 9 was upregulated in cells exposed to 3 mW for 30 min, but not at 30 mW for 3 min. Conclusions The 30 mW UV-A irradiation used in ACXL appears to be safe on cultured LECs in comparison with 3 mW used in CXL. ER -