IP: Dr. David Bernardo Ordiz

Resumen del proyecto: Recent evidence suggest that 50% of the population would have memory T-Cells towards catarrh-causing coronaviruses with cross-reactivity against SARS-CoV-2. Deepening this observation is of vital importance given that, although these patients would be seronegative, the presence of this cellular memory could confer immunity (total or partial) to COVID-19. Such being the case, this would completely change the percentage of patients carrently immunized against the virus. Building on this, our aim is characterize the presence of humoral immunity (specific antibodies by ELISA) and cellular immunity (identification of reactive T-cell clones against SARS-CoV-2 by tetramers and ELISPOT) in patients who have passed COVID-19 (both with good and poor evolution), as well as in healthy controls undiagnosed with COVID-19 and control samples cryopreserved more than 2 years ago, with the aim of ensuring that this last group really represents negative controls not exposed to virus. The identification in this pilot study of the real percentage of people who present cellular and humoral immunity against SARS-CoV-2 (irrespective of having suffered from COVID-19) will open a new field of research with a clear translational activity that would be immediately implemented in the clinical practice both by identifying the actual percentage of the population immunized (totally or partially against SARS-CoV-2) and by allowing other vaccines developed against other coronaviruses (such as SARS-CoV) to be used to immunize the population against COVID- 19.

Entidad financiadora: Consejería de Sanidad, Junta de Castilla y León