Purchase this article with an account.
Xinxin Zhao, Jason Yuan Chong Lim, Xian Jun Loh, Xinyi Su; Hyperbranched EPC polymer enhanced anti-angiogenic activity and the cellular uptake of aflibercept. Invest. Ophthalmol. Vis. Sci. 2022;63(7):296 – F0099.
Download citation file:
© ARVO (1962-2015); The Authors (2016-present)
Intravitreal injection anti-vascular endothelial growth factor (anti-VEGF) for the treatment of retinal diseases is invasive and potentially associated with sight-threatening complications. We previously reported the using of nanomicelle form EPC (nEPC) to topically deliver Aflibercept to the retina in a mouse in-vivo model. EPC is a copolymer, made up by covalently linked polyethylene glycol (PEG), polypropyl glycol (PPG) and polycaprolactone (PCL). We hypothesized that hyper-branched poly(PEG/PPG/PCL/Glycerol urethane) (EPCGs), with additional PEG branches on polymer backbone, will improve cellular penetration. The biological effect from the branched structure was then evaluated based on in-vitro biocompatibility, cellular uptake and ex-vivo angiogenic mice choroidal explant.
- To introduce PEG branches:Glycerol (0.25 and 0.75%) was added during the synthesis of EPC - To form nanomicelles with Aflibercept Polymers were dissolved in the buffer containing required amount of aflibercept.-To quantify cellular uptakenaflibercept was covalent linked with rhodamine - Biological assays:Biocompatibility of EPCG was evaluated using human umbilical vein endothelial cells (HUVECs) with LDH cytotoxicity assayIntracellular uptake was assessed by both direct confocal microscopy and flow cytometry. The anti-angiogenic activity of nanomicelles was evaluated by ex-vivo mice choroidal explant.
The hyperbranched EPCGs are biocompatible with HUVECs. EPCGs were able to inhibit blood vessel sprouting after 48hr exposure to EPCG nanomicelles in a concentration and branching dependent manner. Aflibercept complexed with nanomicelles had increased intracellular uptake into HUVECs and human corneal epithelial cells (hCECs), also in a concentration and branching dependent manner.
Hyperbranched EPCG is biocompatible with HUVEC cells in-vitro. Increased branching induced by glycerol was found to enhance the performance of EPC nanomicelles in two ways: (1) Inhibition of vessel sprouting in mice choroidal explant, (2) Increase intra-cellular uptake of aflibercept, which may potentially translate to increase cornea penetration. This suggests that hyperbranched EPCG might be suitable as a platform for topical drug delivery. Further tests are underway to confirm this.
This abstract was presented at the 2022 ARVO Annual Meeting, held in Denver, CO, May 1-4, 2022, and virtually.
This PDF is available to Subscribers Only