What exactly is ocular herpes, and why is it a problem?

Ocular herpes is an eye infection caused by herpes simplex virus type-1 (HSV-1) and type-2 (HSV-2). It's a significant concern because it can damage the cornea, potentially leading to vision loss. The rise of acyclovir-resistant strains makes it necessary to develop new antiviral treatments to effectively combat this threat to eye health.

What are soluble glycoprotein D receptors, and how might they fight ocular herpes?

Soluble glycoprotein D receptors, such as HVEMIg, nectin-1Ig, and nectin-2Ig, are fusion proteins designed to neutralize the herpes simplex virus. They work by binding to the virus and preventing it from infecting cells. HVEMIg and nectin-1Ig have demonstrated the ability to neutralize HSV infections, offering a potential strategy to prevent and treat ocular herpes and reduce the risk of vision loss.

What did the studies reveal about HVEMIg, nectin-1Ig, and nectin-2Ig in protecting against ocular herpes?

HVEMIg and nectin-1Ig demonstrated strong resistance to ocular herpes in studies with transgenic mice. Mice expressing nectin-2Ig did not show the same level of protection. When wild-type mice were treated with serum containing nectin-1Ig after HSV infection, they experienced a reduction in severe symptoms, highlighting nectin-1Ig's potential as a therapeutic agent.

Why is nectin-1Ig being considered for new eye drop formulations?

Nectin-1Ig is particularly promising as a potential treatment for ocular herpes. It has shown the ability to neutralize HSVs in vitro and reduce severe symptoms in infected mice. The development of nectin-1Ig as an eye drop formulation could provide a significant advancement in treating ocular herpes, offering a new option for patients at risk of vision loss.

Why is this research considered a potential breakthrough in ocular herpes treatment?

This research is important because it explores new ways to combat ocular herpes, especially in light of increasing acyclovir resistance. The development of treatments like nectin-1Ig eye drops could offer a significant advancement in preventing vision loss from HSV-1 and HSV-2 infections. Further studies are needed to fully understand the preventive and therapeutic potential of soluble forms of HVEM and nectin-1.

Protective shield of glycoprotein D receptors against virus particles in a human eye.

Ocular Herpes Breakthrough: Can Soluble Receptors Stop the Virus?

Soraya Malik in Health & Wellness December 2025 • 4 min read.

"New research explores the potential of soluble glycoprotein D receptors to combat HSV-1 and HSV-2 eye infections, offering hope for those at risk of vision loss."

Ocular herpes, caused by herpes simplex virus type-1 (HSV-1) and type-2 (HSV-2), remains a significant threat to corneal health and can lead to vision loss. The increasing prevalence of acyclovir-resistant strains of HSV necessitates the development of novel antiviral agents for effective therapeutic intervention.

Recent studies have explored the potential of fusion proteins containing the ectodomain of HSV glycoprotein D receptors, such as herpesvirus entry mediator A (HVEM), nectin-1, and nectin-2, combined with the Fc portion of human IgG (HVEMIg, nectin-1Ig, and nectin-2Ig, respectively). These fusion proteins have demonstrated antiviral effects in vitro and in vivo, suggesting a promising avenue for combating ocular herpes.

To evaluate the antiviral capabilities of HVEMIg, nectin-1Ig, and nectin-2Ig against ocular HSV infections, researchers at multiple universities conducted a study using transgenic mice. These mice, engineered to express the aforementioned fusion proteins, were ocularly inoculated with HSV-1 and HSV-2 to assess the therapeutic potential of these soluble receptors.

How Can Soluble gD Receptors Protect Against Ocular Herpes?

Protective shield of glycoprotein D receptors against virus particles in a human eye.

The study's findings indicate that transgenic mouse lines expressing HVEMIg and nectin-1Ig exhibited marked resistance to ocular herpes. Conversely, mouse lines expressing nectin-2Ig did not demonstrate the same level of protection. This suggests that HVEMIg and nectin-1Ig play a more significant role in neutralizing HSV infections in the eye.

To further investigate the therapeutic effects of nectin-1Ig, which has the ability to neutralize HSVs in vitro, researchers administered transgenic mouse serum containing nectin-1Ig to the eyes of wild-type mice after HSV infection. The results showed a reduction in severe symptoms in the mice treated with nectin-1Ig serum, highlighting its potential as a therapeutic agent.

HVEMIg and Nectin-1Ig: Transgenic mice expressing these proteins showed strong resistance to ocular herpes.
Nectin-2Ig: Transgenic mice expressing this protein did not show the same level of protection.
Nectin-1Ig Serum: Treatment with serum containing nectin-1Ig reduced severe symptoms in infected mice.

These results suggest that soluble forms of HVEM and nectin-1 warrant further study as potential preventive and therapeutic agents against ocular herpes caused by HSV-1 and HSV-2. Specifically, nectin-1Ig shows promise as a novel eye drop formulation.

The Future of Ocular Herpes Treatment

This research paves the way for new strategies in managing and preventing ocular herpes, especially as acyclovir resistance becomes more common. The development of nectin-1Ig as a new eye drop could offer a significant advancement in treating this vision-threatening condition, offering a beacon of hope for those at risk.