Abstract
Introduction::
Corneal keratocytes undergo injury induced cellular differentiation into activated keratocytes (fibroblasts). Early loss of corneal transparency is predominantly related to changes in number and density of activated keratocytes contributing to impairment of vision in post operative period. Specific targeting of differentiated cell types with therapeutic agents could minimize postoperative haze and scarring.
Purpose::
Based on our previous work we aimed to develop an aptamer specific to activated corneal keratocytes by selectively targeting the Thy-1 (CD-90) surface marker.
Methods::
A Thy-1 specific RNA aptamer was developed using a counter selective molecular strategy (SELEX).A defined stromal injury was created using a femtosecond laser platform. Tissue was cultured in a specifically designed artificial anterior chambers for seven days to allow keratocytes activation. Corneas were then fixed and sectioned prior to labelling with the RNA aptamer. Foreskin fibroblasts, passive keratocytes and a naïve aptamer pool were used as controls.
Results::
There was specific staining of activated keratocytes at the interface of tissue injury which labelled clearly with the CD-90 aptamer( p<0.01). Passive cells remained unlabelled.
Conclusions::
This is a significant step forward in specific cell targeting using an RNA aptamer. These developments bring us a step closer to in-vivo cellular targeting in the human cornea.
Keywords: cornea: stroma and keratocytes • cornea: basic science • cornea: epithelium