Marcoe, G. J. | Search bioRxiv

bioRxiv2026

rAAV prostaglandin-based gene therapy lowers intraocular pressure and preserves optic nerve health in glaucomatous DBA/2J mice

Open-angle glaucoma (OAG) affects approximately 57.5 million individuals worldwide and is characterized by the progressive loss of retinal ganglion cells (RGC) and irreversible optic nerve damage resulting from chronic ocular hypertension. Intraocular pressure (IOP) is the only major modifiable risk factor in OAG and clinical treatments necessarily aim to lower IOP in order to preserve RGCs and prevent vison loss. Pharmacological therapies, such as prostaglandin analog containing eye drops, are known to be effective at reducing IOP, but are critically undermined by poor patient compliance and are unable to control for potentially damaging diurnal fluctuations in IOP, leading to vision loss even in patients diagnosed early. Herein we evaluate the effectiveness of a long-acting, single use, prostaglandin-based recombinant adeno-associated virus (rAAV)-mediated IOP-lowering gene therapy treatment in glaucomatous DBA/2J mice and demonstrate that sustained IOP reduction leads to preservation of both optic nerve anatomy and function in end-stage glaucomatous disease. One Sentence SummaryIOP-lowering gene therapy provides partial anatomical and functional rescue in glaucomatous mouse model following single dose treatment

neuroscience↗

bioRxiv2024

Hepatitis B Virus genomes associate with cellular sites of DNA damage by inducing replication stress

Hepatitis B Virus (HBV) is a leading cause of liver cancer, with almost 300 million infected individuals worldwide. Although HBV-infected patients benefit from drug regimens that help to control chronic infection, they are rarely clinically cured of HBV. The HBV genome persists in the nucleus of infected hepatocytes in the form of a covalently closed circular DNA (cccDNA) molecule, a reservoir of HBV DNA molecules that serve as the template for reactivation of long-term chronic HBV. However, despite playing a central role in the viral life cycle, little is understood about where cccDNA molecules localize, why they are so stable, and how they impact the host nuclear compartment. Perhaps because of this, there are few treatments that target cccDNA, which is critical for eradication of clinical HBV. Here, we show that HBV infection induces a cellular DNA Damage Response (DDR) that is comparable with cells undergoing replication stress, and this cellular replication stress is initiated after the formation of cellular cccDNA molecules. Using a novel high-throughput chromosome conformation capture technology that monitors the localization of HBV cccDNA molecules, we show that cccDNA molecules persist in the vicinity of many cellular fragile sites. Induction of cellular DNA damage leads to relocalization of the viral HBx oncoprotein to DDR sites in an ATM, ATR and DNA-PK dependent manner. Our findings contribute to the understanding of how HBV cccDNA navigates the host nuclear environment, identifying functional targets for development of therapies against HBV infection and resulting liver cancer. ImportanceHepatitis B Virus (HBV) is the leading infectious cause of liver cancer globally. The virus persists in the nucleus long term by forming reservoirs in human liver cells. We have discovered that the HBV DNA localizes to sites on the host genome associated with DNA damage, and in doing so, HBV interferes with the hosts ability to efficiently amplify itself. This results in the induction of cellular DNA breaks, which we propose contributes to eventual cancer progression. Our findings provide new insights into how HBV infection may lead to liver cancer.

microbiology↗