TY - JOUR
T1 - Safety profile of accelerated corneal cross-linking versus conventional cross-linking: a comparative study on ex vivo-cultured limbal epithelial cells
AU - Shetty, Rohit
AU - Matalia, Himanshu
AU - Nuijts, Rudy
AU - Subramani, Murali
AU - Dhamodaran, Kamesh
AU - Pandian, Ramanan
AU - Jayadev, Chaitra
AU - Das, Debashish
PY - 2015/2
Y1 - 2015/2
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 Delta np63 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 Delta np63 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.
AB - 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 Delta np63 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 Delta np63 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.
U2 - 10.1136/bjophthalmol-2014-305495
DO - 10.1136/bjophthalmol-2014-305495
M3 - Article
C2 - 25488945
SN - 0007-1161
VL - 99
SP - 272
EP - 280
JO - British Journal of Ophthalmology
JF - British Journal of Ophthalmology
IS - 2
ER -