Researchers at Vanderbilt University Medical Center have successfully isolated human monoclonal antibodies against the influenza B virus, which poses a significant public health threat, especially to vulnerable populations such as children, the elderly, and immunocompromised individuals. Seasonal flu vaccines cover both influenza A and B, but may not stimulate the broadest range of immune responses against both viruses, especially in people with weakened immune systems. Small-molecule drugs that target neuraminidase, a major surface glycoprotein of the influenza virus, are effective in treating early infections but less so in severe cases, particularly for influenza B infections.
Published in the journal Immunity, the Vanderbilt researchers detail how they isolated two groups of monoclonal antibodies from the bone marrow of an individual who had previously been vaccinated against influenza. These antibodies targeted distinct parts of the neuraminidase glycoprotein on the surface of influenza B. One of the antibodies, FluB-400, demonstrated broad inhibition of virus replication in human respiratory cells in laboratory settings. It also showed promising results in protecting against influenza B in animal models when administered through injection or intranasally.
The researchers suggested that intranasal administration of antibodies could be more effective and have fewer systemic side effects than traditional routes like intravenous infusion or intramuscular injection. By trapping the virus in nasal mucus, intranasal antibodies may prevent infection of the underlying epithelial surface, providing a localized defense against the virus. These findings support the further development of FluB-400 for the prevention and treatment of influenza B, as well as guiding efforts towards the development of a universal influenza vaccine.
Lead author James Crowe Jr., MD, emphasized the growing importance of antibodies as a tool for preventing and treating viral infections. Crowe is the director of the Vanderbilt Vaccine Center, which has successfully isolated monoclonal antibodies against various viral infections, including COVID-19. Co-author Rachael Wolters, DVM, PhD, a former graduate student in the Crowe lab, along with a team of VUMC researchers, contributed to the study. Funding for the research was provided by various National Institutes of Health grants and contracts, as well as support from the Collaborative Influenza Vaccine Innovation Centers program.
Overall, the research conducted by the Vanderbilt University Medical Center highlights the potential of monoclonal antibodies, particularly FluB-400, in combating influenza B infections. The findings pave the way for the development of more effective prevention and treatment strategies for this virus, which continues to pose a significant health challenge to vulnerable populations. Through innovative approaches like intranasal antibody administration, researchers aim to enhance the efficacy and reduce the side effects of antiviral therapies, ultimately contributing to the advancement of universal influenza vaccines.