Abstract
Purpose :
To identify and describe changes of proinflammatory cytokines in tears from patients treated with corneal crosslinking
Methods :
40 eyes from 20 patients with progressive keratoconus were included in this study (20 case eyes and 20 control eyes). VibeX Rapid™ (0.1% Riboflavin, Saline, HPMC) was topically applied to the cornea after epithelium removal, 1 drop was instilled every 2 minutes for 10 minutes, UVA light from the Avedro KXL® System was applied to activate it for Accelerated Cross-Linking, irradiation was conducted at 30 mW/cm2 continuously for 4 minutes (total energy: 7.2 J/cm2). A bandage contact lens was applied post-procedure and patients were started on topical antibiotics (moxifloxacin hydrochloride 0.5%) and steroids (prednisolone acetate 0.12%), which were tapered at 1 month after complete epithelial healing. All patients were reviewed at 1 day, 1 week, 1 month and 3 months after procedure. Tears samples were taken from both eyes (case eye and control eye) at 7 days before crosslinking, 1 month and 3 months after. For taking samples 1 balanced saline solution drop was instilled into inferior conjunctival sac, then tear sample was taken with a capillary tube and deposited in a 0.5 ml tear container. Tear samples were deposited on nitrocellulose membrane using Proteome Profiler Human XL Cytokine Array® kits (with doble points of antibodies for 105 different cytokines). Proteome cuantification was made by a photo documentator G-BOX imaging system® and analized with Vision Works LS® software
Results :
At 1 month after crosslinking, biologically significant changes (more than 2-fold changes) were found. Significative decrease in: PDGF-AA, I-TAC, PF-4, CRP, VEGF, Resistin, HGF, IL-1ra, MMP-9, IL-19, SDF-1α, TIM-3 and Relaxin 2. At 3 months decrease: G-CSF, IL-24, adiponectin among others. At 3 months after, comparing treated eyes versus non treated, significative increase in CD31 and RANTES were found. Significative decrease in: ST2, MCP-3, IL-12p70, IL-22 and adiponectin
Conclusions :
Crosslinking not only changes molecular structure in human cornea by increasing its strength. We found that this treatment is also related with significative decrease in proinflammatory cytokines, such as MMP-9, CRP and IL-19. More studies and longer tracing are necesary to prove if these changes on inflammatory molecular profile last in time and to correlate them with clinical outcome of patients
This abstract was presented at the 2019 ARVO Annual Meeting, held in Vancouver, Canada, April 28 - May 2, 2019.