Nasal vaccine against COVID-19 prevents infection in mice

Scientists at the University of Washington School of Medicine in St. Louis have developed a vaccine targeting the SARS-CoV-2 virus. It can be administered as a single dose from the nose and is effective in preventing infection in mice susceptible to the novel coronavirus. The researchers then plan to test the vaccine in nonhuman primates and humans to see if it is safe and effective in preventing COVID-19 infections.

Studies are available online in journals cell..

Unlike other COVID-19 vaccines in development, this vaccine nose, Often the first site of infection. In a new study, researchers found that the nasal delivery route produces a strong immune response throughout the body, which was particularly effective for the nose and nose Airway, Prevent the infection from establishing itself in the body.

“I was surprised to see a strong immune response in the cells of the lining of the nose and upper respiratory tract and the strong protection from infection by this virus,” he said. Herbert S. Gasser Professor of Medicine, Professor of Molecular Microbiology, Pathology and Immunology. “These mice were well protected from the disease, and some mice had evidence of sterile immunity with no sign of infection after the mice were challenged with the virus.”

Develop vaccineResearchers have inserted a viral spike protein. Coronavirus It infects cells within another virus called adenovirus, causing a cold. But scientists tweaked the adenovirus, making it impossible for it to cause disease. The innocuous adenovirus carries spike proteins to the nose, allowing the body to mount an immune defense against the SARS-CoV-2 virus without getting sick. In another innovation beyond nasal administration, the new vaccine incorporates two mutations in the spike protein, stabilizing it in a particular form that is most helpful in forming antibodies to it.

“Adenovirus is the basis of many investigational vaccines against COVID-19 and other infectious diseases such as Ebola virus and tuberculosis, and although records of safety and efficacy are good, nasal administration of these vaccines Little research has been done.” Co-Senior Author David T. Curiel, MD, Ph.D. , A prominent professor of radiation oncology. “All other adenovirus vaccines being developed for COVID-19 are delivered by injection into the arm or thigh muscle. Our results are surprising and promising because the nose is a new route. It is also important to have such robust results in a single dose: immune response, a vaccine that requires two doses for complete protection may not be given a second dose for various reasons. Is less effective.”

There is Influenza vaccine Called FluMist delivered through the nose, it uses a weakened form of the live influenza virus and cannot be given to certain groups, including those whose immune system is compromised by diseases such as cancer, HIV, and diabetes .. In contrast, the new COVID-19 intranasal vaccine in this study is probably safer because it does not use a replicative live virus.

The researchers compared the vaccine given to mice in two ways: intranasal and intramuscular injection. The injection elicited an immune response that prevented pneumonia, but it did not prevent nasal and lung infections. Although such a vaccine may reduce the severity of COVID-19, it does not completely prevent the infection or prevent the infected individual from spreading the virus. In contrast, the nasal delivery route prevents infection in both the upper and lower respiratory tract (nose and lungs), and vaccinated individuals can spread the virus or cause infection elsewhere in the body. It suggests that you do not.

The researchers said the study was promising, but warned that so far vaccines have only been studied in mice.

“We have this intranasal vaccine Non-human primates “We’re planning on moving to human clinical trials as soon as possible,” said Diamond, “but optimistic, but there’s a need for an appropriate evaluation pipeline. In these mouse models, the vaccine It’s very defensive: we’ll start the next round of research and eventually test it in people to see if it can not only prevent, but also elicit, a type of protective immunity. I am looking forward to it infection It also suppresses pandemic infections Virus”