Albumin Nanoparticles Can Deliver and Express Flt23k Intraceptor for Long Term

Abstract

Purpose: : To determine whether albumin nanoparticles can deliver and express Flt23K intraceptor, a recombinant construct of domains 2 to 3 of VEGFR-1 (Flt) coupled with an endoplasmic reticulum retention signal (KDEL), for long term.

Methods: : FITC conjugated biodegradable albumin nanoparticles encapsulating pCMV.Flt23K and empty pCMV were developed as a lyophilized product that is easily redispersed in an aqueous medium. Nanoparticles were injected into the corneas of BALB/c mice and observed for 4 weeks. Entry of nanoparticles into corneal cells was demonstrated through transmission electron microscopy and confocal imaging. FLt2-3k expression and localization was observed by IP and western blotting

Results: : TEM confirmed that nanoparticles were taken up into the corneal keratocyte cytoplasm. FITC-conjugated nanoparticles were expressed in corneal keratocytes and fluorescence could be observed up to 4 weeks. Flt23K was expressed in the corneas for 5 weeks. Organelle fractionation confirmed the localization of Flt23K in the endoplasmic reticulum.

Conclusions: : Albumin nanoparticles can deliver and express the FLT2-3K intraceptor for long term into cornea and seem promising for drug delivery. Sustained nonviral gene therapy to the cornea seems viable as a therapeutic approach.

Keywords: cornea: stroma and keratocytes • vascular endothelial growth factor • gene transfer/gene therapy