CeO2 Nanoparticles-assisted stem-based cell therapy: an innovative nanopharmaceutical approach to treat retinal degenerative diseases

The main aim of CELLUX is to develop a novel pharmaceutical based on CeO2 nanoparticles (NPs) eye drops to treat Age Macular Degeneration (AMD) that in combination with stem cell-based therapeutic strategies, can stop degeneration and restore vision.

The progression of AMD is associated with an increase of oxidative stress and inflammatory response in the eye leading to retinal cell death. This chronic disease represents a major cause of blindness in elderly people, and affects millions of people worldwide.

CeO2 NPs have antioxidant properties due to a unique electronic structure that when reduced to the nanoscale, oxygen defects appear at their surface, behaving as sites for free radical scavenging.

The project is financed via ERA NET EuroNanoMed3 program and it is coordinating by University Hospital (VHIR) Barcelona. The consortium consists of six partners from five countries: Spain, Norway, Italy, Czech Republic and France.

The project started in January 2020 and will be performed in a period of 36 months. The project tasks are broken into 6 work packages (WPs).

NILU is involved WP2. “Mechanistic effects and safety of the NPs in vitro” and is responsible for the task 2.1: Cellular interaction and distribution of CeO2 NPs.

NILU will study safety of the CeO2 NPs by the endpoints cytotoxicity (alamarBlue assay) and genotoxicity (enzyme-linked version of the comet assay). Oxidative stress at the DNA level, as well as DNA strand breaks will be studied by the comet assay. Further, mechanisms of interaction of CeO2 NPs with cells will be studied by confocal microscopy (cellular uptake, endocytosis and exocytosis). Antioxidant protective effect of CeO2-NPs will be compared with effect of known antioxidants as ascorbic acid, alpha-tocopherol, beta-carotene.

In the last year NILU has:

i) Established a retinal cell model (RPE) at NILU`s premises

ii) Performed cyto- and genotoxicity testing of the oxidant Tertiary-butyl hydroperoxide (TBH) and of CeO2 NPs produced by the partners in the project on the well-known cellular model A549 as well as in RPE cells.

iii) Investigated the antioxidant protection against DNA damage with known antioxidants on a well-known cellular model (A549) The known antioxidants ascorbic acid, alpha-tocopherol and beta-carotene were tested for their capacity to protect cells from oxidative DNA damage, applying the comet assay.

Experiments are ongoing to test these antioxidants in combination with TBH and CeO-NPs, measured by cell viability and DNA damage. No cell death nor induction of DNA damage was measured after exposure to CeO-NPs.

NILU also investigated cellular interaction of CeO-NP and by confocal microscopy. NILU participated with several scientist at the consortium meetings. Experimental work is a bit delayed due to COVID 19 and laboratories lock down.