Year: 2011
Type: article
Abstract: Purpose.To determine if canine lens epithelial cells (LEC) contain the hyaluronic acid (HA) receptors CD44 and RHAMM, and if HA can impact posterior capsular opacification (PCO) formation in vitro.Methods.Normal (n=10) and cataractous (n=10) canine LEC were evaluated using immunohistochemistry and RT-PCR for expression of CD44 and RHAMM.In vitro models of PCO formation were used to determine if various HA concentrations altered LEC migration.A one-millimeter scratch was created in cultures of confluent canine LEC.Cells were treated with 0, 0.02, 0.012, or 1.0 mg/mL (n=6 per group) of HA dissolved in culture media.Migration of LEC into the scratch was quantified.Mock cataract surgery was performed on canine cadaver eyes.Capsules were re-distended using one of the following (n=6 per group): PBS only, hydroxypropyl methylcellulose viscoelastic, 1.2% HA (12 mg/ml HA) viscoelastic, or 2.0% (20 mg/ml HA) HA viscoelastic.LEC migration within the capsule was evaluated.Results.Normal and cataractous LEC were positive for CD44 and RHAMM protein and mRNA.CD44 showed a statistically significant increase (p<0.01) in mRNA expression in LECs treated with 1.0 mg/ml of HA as compared to the control and 0.02 mg/ml HA iii Cultured LECs that were treated with 1.0 mg/mL of HA compared to control showed a significantly smaller area devoid of cells (p=0.001) in the scratch test model compared with the control.The number of LECs increased when capsules were treated with 2% HA (20mg/ml HA) viscoelastic as compared to control (p < 0.0109).Conclusions.Canine LEC possess receptors to respond to HA signaling.Treatment with HA significantly increased the rate of LEC migration in a dose dependent manner.CD44 was upregulated in canine LEC after being treated with 1.0mg/ml of HA.RHAMM was slightly upregulated in canine LEC after being treated with 1.0mg/ml of HA.Viscoelastics containing HA promoted LEC migration and proliferation in vitro.The introduction of exogenous HA in the form of viscoelastics during cataract surgery may promote LEC migration and contribute to PCO formation in vivo.I am endlessly grateful to Heather Chandler of the Laboratory for Molecular and Comparative Ophthalmology for the guidance, patience, positive encouragement, infinite hours of editorial critiques, and availability for my questions.I am appreciative of all the histopathology preparation techniques of Alan Flechtner in Veterinary Biosciences for all of his unparalleled work preparing our lens capsules.vi Thank you to Elizabeth Lutz for all of her help with data acquisition in the Laboratory for Molecular and Comparative Ophthalmology.Her dedication to propelling this project is appreciated.Thank you to Mirunalni Thangavelu of the Laboratory for Molecular and Comparative Ophthalmology for all of her help with laboratory techniques as well as answering any question that came up.I would also like to thank Christie Shover for her help in data acquisition.Thank you to John Bonagura
Author: David J. Haeussler
Institution: The Ohio State University
Language: English
Subfield: Ophthalmology
Field: Medicine
Domain: Health Sciences
Open Access status: green
OpenAlex ID: W2597896236