Abstract
Purpose :
To develop an animal model for pterygium using subconjunctival injection of murine fibroblast cells (NIH 3T3 cell line) in white New Zealand rabbits
Methods :
Under general and topical anesthesia with tetracaine hydrochloride, six 3 month-old white New Zealand rabbits received subconjuntival injection of 20,000 murine fibroblast cells (NIH 3T3 cell line) and 5 µL of Matrigel(Corning Inc, NY, US) on the perilimbal temporal bulbar conjunctiva of the right eye using a 1ml 30G needle. Left eyes were injected with 5 µL of Matrigel under the perilimbal temporal bulbar conjunctiva (control). Eyes were photographed under a magnification of 16x using a 12 megapixel digital camera attached to the microscope (WPI, Inc. FL, US) on day 1, 3 and 7. Conjunctival vascularization was measured on day 1,3 and 7 by analyzing images using Adobe PhotoshopCS5 (Adobe Inc,San Jose,CA) color histograms to measure red pixel saturation on a 6x6 mm area on the site of injection. Area of corneal and conjunctival fibrovascular tissue formation was assessed by analyzing the images on day 3 and 7 using area measurement software (Adobe Photoshop CS5). Statistical analysis was performed using t-test for mean comparison, statistical significance was considered with a p value <.05
Results :
Red pixel saturation for right and left eyes was 102.53±11.07pxs and 104.84±8.34pxs (p=.609), 176.15±6.35px and 168.29±18.89pxs (p=.325), 221.58±33.85pxs and 168.70±17.75pxs (p=.006) on day 1, 3 and 7 respectively. Area of fibrovascular tissue on the site of injection in the right and left eyes was 14.32±3.47mm2 and 8.41±2.08mm2 (p=.002), 41.18±4.40 mm2 and 14.69±2.81 mm2 (p<.001) on day 3 and 7 respectively. Significant difference was observed between day 3 and 7 on right eyes (p<.001) and left eyes (p=.002) when comparing the area of fibrovascular growth. Red pixel saturation was higher for both eyes on day 7 when compared to day 3, but was only the different was only significant for right eyes (p=.017)
Conclusions :
Subconjunctival injection of murine fibroblast cells and Matrigel in white New Zealand rabbits was more effective for inducing conjunctival vascularization and fibrovascular tissue growth on the site of injection and surrounding cornea than subconjunctival Matrigel alone. A novel animal model for pterygium is presented with potential use for research on molecular mechanisms of pathogenesis and new treatment strategies.
This is an abstract that was submitted for the 2016 ARVO Annual Meeting, held in Seattle, Wash., May 1-5, 2016.