Characterizing the role of the eye as a site for topical vaccination against respiratory viruses

The eye is covered by a mucus membrane that is constantly exposed to viruses. Despite this, the eye rarely becomes infected due to a powerful immune system responsible for protecting our vision. When an eye is exposed to a virus, viral particles travel down to regions in the body that activate immune cells, necessary to fight the virus. These cells are then distributed back to the initial site of infection to provide protection. In light of the recent pandemic, we need a better way to study and combat viruses that affect our respiratory system. Given the eyes are accessible, and its connection to the body, they represent an ideal starting point to help us better understand how to deal with new viruses. To study how the eye is involved in protecting us against respiratory viruses, we will develop a model. Here, we will apply a known respiratory virus to the surface of the eyes of mice and examine how the immune system responds. We will measure an immune response in the lining of the eye, nose, lymph nodes and spleen. Since the eye is a first point of contact for viruses, we propose that exposing the eye to a virus can lead to protection against future infection. To test our theory, we will use a mouse coronavirus capable of causing severe respiratory disease and test how applying this virus to the eyes can lead to fast and long-lasting immunity. This will form the basis for developing the first topical eye vaccine. By administering viral eyedrops before the start of respiratory disease, we expect to observe protection against respiratory infection and therefore prevent death. We will also examine how the tears around our eyes contribute to this immune protection. This study will be the first of its kind and help us understand how the eye shapes our immune system in fighting infections. Moreover, this work will lay the foundation for developing an eyedrop as a novel, rapid and more accessible vaccine, which may prove to be more powerful at preventing infection.