Abstract
Purpose: :
Corneal endothelium is an ideal target for gene therapy approaches thanks to its anatomical location at the posterior surface of the cornea and its monolayer structure. Lentiviral vectors have been shown by our group to be suitable vectors for the transfer of DNA into corneal endothelial cells (EC). Searching for an alternative to these HIV-based vectors, aim of this study was to determine the suitability of non-pathogenic adeno-associated viral vectors (AAV) for gene transfer to EC.
Methods: :
Flowcytometric comparison of protein expression after EC transduction using a lentiviral vector or AAV 2/2 with GFP in murine EC (Balb/C) and in human EC (cell line and primary cells). Proof of principle experiment to demonstrate the functionality of lentiviral gene transfer of the anti-apoptotic proteins Bcl-xL.
Results: :
Kinetics of the protein expression after transduction of EC using lentiviral vector are considerably different compared to gene transfer using AAV. Contrary to AAV with protein expression showing a plateau after two to three weeks, lentiviral gene transfer results in a very rapid expression of reporter protein. In addition, we detected significant differences in transduction rates between human and murine EC lines as well as betweeen human EC lines and human corneas (plateau at 70% versus 50% GFP-positive cells with AAV, versus 90-95% with lentivirus).
Conclusions: :
AAV vectors seem to be a suitable alternative to lentiviral vectors for gene transfer to EC. Considering the storage of human donor corneas in eye banks in organ culture over four weeks, translation of AAV from bench to bedside, e.g. to reduce apoptosis in corneas, seems to be a promising approach for future gene transfer into donor corneas.
Keywords: cornea: endothelium • gene transfer/gene therapy • apoptosis/cell death