Abstract
Purpose :
Genotoxicity testing is necessary to address potential mutagenic characteristics of pharmaceutical candidates and some medical devices. Adapting such tests to contact lens multipurpose solutions (MPS) may be required due to their anti-microbial nature or regional regulatory requirements. We report the use of a novel methodology for genotoxicity and biocompatibility evaluation of MPS.
Methods :
In a novel Miniscreen AMES test, Salmonella His-dependent strains TA98 and TA100 were incubated with test articles for 48 hr, then revertant, His-independent colonies counted. For AMES assays, 3 additional bacterial strains (TA1535, TA1537, Wp2uvrA-) were also tested. For Chromosome Aberration Assays, CHO cells were exposed to test articles for 4 hrs, then analyzed for chromosome breakage or loss. Each assay was conducted with naive and S9-Arclor 1254-metabolically activated cells. RevitaLens® MPDS or contact lens (Acuvue Advance® and Acuvue 2® brand) extracts prepared by 72 hr incubation at 37°C in controls or MPS (3cm2 per 1ml) were tested in triplicate. Prior to assays with the RevitaLens® MPDS disinfectant ingredient, Alexidine Dihydrochloride (ALX), a 200 µg/ml stock of ALX was diluted for dose range tests identifying TA100 or CHO cytotoxicity levels to determine the amount of ALX appropriate for each assay.
Results :
Miniscreen AMES and AMES show RevitaLens® MPDS and the contact lens extracts did not increase the number of revertant colonies compared to saline, suggesting nonmutagenicity (n=3, p>0.7). The test articles also did not increase chromosome aberrations, indicating they are non-clastogeneic. For assays on ALX, cytotoxicity in TA100 was found above 50ug/ml and 12ug/ml, with and without activation, respectively. Below these cytotoxic limits, ALX did not increase the frequency of revertants in the AMES assay above saline (n=3, p>0.3). Cytotoxicity in CHO cells was observed above 20ug/ml and 2ug/ml when activated and not, respectively. Non-cytotoxic concentrations demonstrated no chromosome changes compared to saline (n=3, p>0.3).
Conclusions :
Results from novel and standard genotoxicity assays demonstrated that RevitaLens® MPDS and its disinfectants, ALX and PQ-1 are not genotoxic or clastogenic. Novel miniscreens are beneficial and accurate for future biocompatibility testing on MPS and other medical devices requiring genotoxicity evaluation.
This is an abstract that was submitted for the 2016 ARVO Annual Meeting, held in Seattle, Wash., May 1-5, 2016.