Abstract
Purpose: :
To investigated the distribution of FGF-2 and perlecan within the bovine lens capsule.
Methods: :
Bovine lens epithelial cells were gently removed from the lens capsule by a curved tweezers. The lens capsules were fixed with a glutaraldehyde and formaldehyde combination, which preserved the epitopes for FGF-2, perlecan and collagen IV. The distribution of these three components was then measured by quantitative immunogold labelling of bovine lens capsule samples. These were flat mounted before being prepared for high resolution of a Hitachi SU70 scanning electron microscope. Images were collected and then tiled to document labelling across the entirety of the anterior and posterior lens capsule. Gold particles were counted using the ImageJ software. The data were tested for significance using the student T-test.
Results: :
Both FGF-2 and perlecan epitopes were significantly more abundant in the equatorial region than either the anterior or posterior regions of the lens capsule. Interestingly, the posterior of the lens capsule was more heavily labelled than the anterior surface. Collagen IV epitopes were equally abundant in the anterior and equatorial regions, but were significantly decreased on the posterior lens capsule.
Conclusions: :
The distribution of FGF-2 in bovine lens capsule fits the current hypothesis that there is an anterior-posterior gradient of FGF-2 available to lens epithelial cells. FGF-2 and its potential matrikine partner perlecan are concentrated in the equator. We suggest that the significant levels of FGF-2 and perlecan on the posterior lens capsule are a significant factor in the development of PCO.
Keywords: differentiation • extracellular matrix • growth factors/growth factor receptors