Table 1.
Phototoxicity criteria in NRU test.
Fig 1.
Spectral properties of chlorpromazine (positive control), ciprofloxacin, levofloxacin, lomefloxacin, norfloxacin, and tetracycline (test substances), and L-histidine and sodium lauryl sulfate (negative controls).
Fig 2.
Irradiation sensitivity of SIRC cells.
Cell viability showed a dose-dependent response to irradiation, with 85.2%±4.9% after irradiation at 5 J/cm2, 73.8%±3.4% after irradiation at 10 J/cm2, and 66.4%±2.9% after irradiation at 20 J/cm2. The data are expressed as the mean ± S.E. (n = 5).
Fig 3.
Phototoxicity evaluation of the ophthalmic agents in SIRC cells: A) chlorpromazine (positive control), B) ciprofloxacin, C) levofloxacin, D) lomefloxacin, E) norfloxacin, F) tetracycline, G) L-histidine (negative control), and H) sodium lauryl sulfate (negative control). The closed circle and open circle represent data from the nonirradiated groups and UV-irradiated groups, respectively. Phototoxic chemicals induced dose-response curve shift with UV-irradiation. Fitting of the curve to the data was performed by a non-linear regression method (n = 6).
Table 2.
Comparison of phototoxicity test results from in vitro SIRC, 3D human model and 3T3 NRU phototoxicity test.
Fig 4.
Hematoxylin and eosin staining of 3D human cornea models (HCE) of the ophthalmic agent, with and without UV irradiation of 6 J/cm2: A) chlorpromazine (positive control), B) ciprofloxacin, C) norfloxacin, D) tetracycline, E) L-histidine (negative control), and F) sodium lauryl sulfate (negative control).