Gilbert was involved with the development and testing of the universal flu vaccine. Unlike conventional vaccinations, the universal flu vaccine did not stimulate the production of antibodies, but instead triggers the immune system to create T cells that are specific for influenza.[12] It makes use of one of the core proteins (nucleoprotein and matrix protein 1) inside the Influenza A virus, not the external proteins that exist on the outside coat.[13] As the immune system weakens with age, conventional vaccinations are not effective for elderly.