The human immune system is reactive to more than just the viral protein on which researchers have focused to date. This is relevant for tests and potential vaccines. Research teams from Ruhr-Universität Bochum (RUB) and Essen University Hospital have identified the parts of the SARS-Cov-2 virus to which the human immune system reacts: in addition to the spike protein, which has been the focus so far, two other proteins can also trigger a strong immune response. This discovery is relevant for the development of diagnostic tests and vaccines. “We shouldn’t focus exclusively on the spike protein,” says the principal investigator of the study Professor Nina Babel from the Centre for Translational Medicine at Marien Hospital Herne, the RUB’s university hospital. The study, which is currently being reviewed by independent experts, is available online on a preprint server.