A multi-purpose influenza vaccine
Annual influenza virus epidemics are characterised by extensive variability and infectivity. The high mutation rate of the virus requires the ongoing development of vaccines to protect against flu-like illness. To this aim, the EU-funded ‘Development of influenza delNS1 virus as a vector for foreign antigens’ (Chimeric Vaccines) project focused on developing a novel chimeric vaccine against avian and human influenza. To achieve this, project scientists used an attenuated, replication deficient influenza virus vector to express antigens that had a deletion of the immunosuppressant factor NS1. First, the vector was optimised to be able to effectively express antigens of foreign pathogens. Partners developed a reverse genetics-based tool that allowed the fast and efficient generation of new viral constructs. Several constructs were tested for the successful expression of foreign antigens and for vector stability. Based on the sequences from human and avian influenza viruses, scientists predicted promising immunogenic epitopes which were subsequently expressed by the delNS1 virus vectors. The potential of these vectors in terms of immunogenicity and safety was verified in suitable animal models. The chimeric vaccine developed during the project was brought a step closer to the marketable stage through a patent application. Importantly, the delNS1 vector exhibited the potential to be developed into a flexible chimeric vaccine that would be useful for a variety of diseases.
