Vaccine Found to Protect Against Enhanced Respiratory Disease

Researchers from Georgia State University found a virus-like particle vaccine that can prime the body’s immune response and may prevent a severe respiratory disease.

This study  offers a solution to the formalin inactivated respiratory syncytial virus (FI-RSV) vaccine that did not protect children.

The FI-ESV vaccine was reported to actually cause severe respiratory illness, which is a vaccine-enhanced respiratory disease (ERD), after initially being infected with respiratory syncytial virus (RSV).

RSV, is a common respiratory virus that usually causes mild, cold-like symptoms. Most people recover from RSV in a week or two. 

But RSV can be serious, especially for infants and older adults.

In fact, according to the Centers for Disease Control and Prevention, RSV is the most common cause of bronchiolitis (inflammation of the small airways in the lung) and pneumonia (infection of the lungs) in children younger than 1 year of age in the United States. It is also a significant cause of respiratory illness in older adults.

These researchers found immunizing mice with virus-like particles containing RSV fusion proteins before administering the FI-RSV vaccine and exposing mice to RSV prevented FI-RSV vaccine-enhanced lung inflammation and the invasion of eosinophils, which are disease-fighting white blood cells.

The study’s findings are published in the journal Virology.

ERD that results from the FI-RSV vaccination has led to hospitalization in 80 percent of patients and the deaths of two children.

“This study provides insight into mechanisms responsible for ERD caused by FI-RSV vaccination and developing safe RSV vaccines,” said Dr. Sang-Moo Kang, lead author and professor in the Institute for Biomedical Sciences at Georgia State.

“We demonstrated that priming mice with virus-like particles that present RSV fusion proteins shifted immune response and resulted in preventing ERD. A vaccine that primes protective innate and adaptive immune responses that prevent ERD still remains to be developed, but our findings could pave the way to creating a safe vaccine with these capabilities,” said Kang.

ERD is characterized by mucus production in the airways, severe lung inflammation, immune responses by T helper type 2 (Th2) cells and infiltrations of eosinophils into the lining of the respiratory tract.

No conflicts of interest were disclosed by the co-authors of the study, which included Drs. Young-Tae Lee, Ki-Hye Kim, Eun-Ju Ko and Young-Man Kwon, Ph.D. student Youri Lee of Georgia State and Dr. Hye Suk Hwang of both Georgia State and Chonnam National University Medical School in the Republic of Korea.

Sang-Moo Kang, professor at Georgia State University, is focused on research to design and develop effective vaccines against viral diseases such as influenza virus and respiratory syncytial virus, to better understand vaccine-induced protective immune mechanisms, to study pathogen-induced inflammation and to develop anti-inflammatory therapeutics.

The study is funded by the National Institute of Allergy and Infectious Diseases of the National Institutes of Health.