This report aimed to explore whether certain inflammatory mediators were absorbed, extracted, or bound by various contact lens materials.
Comfilcon A, balafilcon A, omafilcon A, and etafilcon A were soaked in 500 and 100 pg/mL of interleukin-8 (IL-8), matrix metalloproteinase-9 (MMP-9), or interleukin-1 receptor antagonist (IL-1Ra), and also in combined solutions of inflammatory mediators (500 pg/mL or 100 pg/mL) separately. Lenses were then extracted in 1:1 2% trifluoroacetic acid:acetonitrile. The extracted and residual concentrations of inflammatory mediators were determined using enzyme-linked immunosorbent assays. Absorbed (control-residual) and firmly bound (absorbed–extracted) concentrations were calculated for analysis.
More MMP-9 was absorbed by omafilcon A (466±9 pg/mL) than balafilcon A (P=0.006; 437±11 pg/mL) or etafilcon A (P=0.001; 428±13 pg/mL) when soaked in 500 pg/mL, but no differences in 100 pg/mL. More MMP-9 remained firmly bound to omafilcon A (P=0.03; 174±3 pg/mL), comfilcon A (P=0.049; 168±34 pg/mL), and balafilcon A (P=0.01; 186±14 pg/mL) than etafilcon A (128±22 pg/mL). There were no differences in IL-8 absorption between lenses; however, more IL-8 remained firmly bound to omafilcon A (P=0.01; 336±25 pg/mL) than etafilcon A (106±133 pg/mL) when soaked in 500 pg/mL. No differences were found in concentrations of absorbed or firmly bound IL-1Ra between materials. When the mediators were combined, IL-8 was absorbed more in etafilcon A (P=0.03) than in other lens materials, but the absorbed IL-8 did not remain firmly bound.
The uptake and extraction of inflammatory mediators from contact lenses was affected by competitive binding between the mediators.
State University of New York College of Optometry (C.C., K.R.), New York, NY; School of Optometry and Vision Science (C.C., M.W.), University of New South Wales, Sydney, NSW, Australia; Center for Translational Ocular Immunology (C.C.), Tufts Medical Center, Boston, MA; and University of Houston College of Optometry (K.R.), Houston, TX.
Address correspondence to Cecilia Chao, M.Optom., Ph.D., F.A.A.O., Tufts Medical Center; e-mail: firstname.lastname@example.org
The authors have no funding or conflicts of interest to disclose.
Parts of the results of this study have been reported as an abstract at the ARVO meeting, 2017, Baltimore, MD.
Accepted December 16, 2018