Promising Results for Experimental Bird Flu Vaccine in Animal Studies

A novel bird flu vaccine under development at the University at Buffalo has shown remarkable success in protecting mice against a deadly strain of the avian influenza virus. The research, detailed in a study published in Cell Biomaterials, focuses on the H5N1 variant called 2.3.4.4b, which has caused extensive outbreaks among wild birds, poultry, and even mammals such as dairy cattle and cats.

The innovative vaccine employs a platform that precisely delivers two key viral proteins: hemagglutinin (H5) and neuraminidase (N1). These proteins stimulate the immune system to recognize and combat the virus effectively. Unlike traditional bird flu vaccines that mainly target H5, this platform enables the inclusion of N1, enhancing the vaccine's potential to adapt to evolving strains.

The team developed a method involving 'his-tags'—short amino acid sequences attached to the proteins—that bind strongly to cobalt-based nanoparticles, creating a robust and quick attachment process akin to a magnet. This approach allows for efficient and rapid vaccine manufacturing. To boost immune response, adjuvants like QS-21 and MPLA were incorporated into the formulation.

In animal trials, mice received doses with H5 alone, N1 alone, or both combined. Results showed that the H5-only vaccine conferred complete protection, with vaccinated mice exhibiting no signs of illness, weight loss, or virus in the lungs. N1 alone provided partial protection, reducing illness severity but not preventing infection entirely. The combination vaccine also achieved full protection, demonstrating that H5 plays a critical role in eliciting immunity. While N1 does not neutralize the virus directly, antibodies against it help reduce viral replication and illness severity.

Interestingly, the vaccine platform has previously undergone Phase II and III clinical trials as a COVID-19 vaccine candidate in South Korea and the Philippines, in partnership with UB spinoff POP Biotechnologies and EuBiologics. The platform’s versatility stems from its use of nanoparticle technology, which signs this approach as a promising candidate for rapidly producing effective bird flu vaccines.

Because the vaccine is recombinant—using genetic fragments rather than live or inactivated virus—it can be produced more swiftly and efficiently without relying on eggs, a common but slower method for current flu vaccines. This makes it a significant step forward in preparing against increasingly resistant and diverse bird flu strains.

Further research will explore different doses, schedules, and conditions to optimize this promising vaccine candidate. Overall, these findings represent an encouraging advancement in efforts to develop more adaptable, potent, and fast-producing vaccines against avian influenza.