SARS-CoV-2 infection drives a glycan switch of peripheral T cells at diagnosis

Alves, I.; Vicente, M. M.; Gaifem, J.; Fernandes, A.; Dias, A. M.; Rodrigues, C. S.; Oliveira, J. C.; Seixas, N.; Malheiro, L.; Abreu, M. A.; Castro, R. S. e.; Pinho, S. S.

COVID-19 is a highly selective disease in which SARS-CoV-2 infection can result in different clinical manifestations ranging from asymptomatic/mild to severe disease that requires hospitalization. Here, we demonstrated that SARS-CoV-2 infection results in a glycosylation reprogramming of circulating lymphocytes at diagnosis. We identified a specific glycosignature of T cells, defined upon SARS-CoV-2 infection and apparently triggered by a serological factor. This specific glycan switch of T cells is detected at diagnosis being more pronounced in asymptomatic patients. We further demonstrated that asymptomatic patients display an increased expression of a viral-sensing receptor, through the up-regulation of DC-SIGN in monocytes. We showed that higher levels of DC-SIGN in monocytes at diagnosis correlates with better COVID-19 prognosis. These new evidences pave the way to the identification of a novel glycan-based response in T cells that may confer protection against SARS-CoV-2 infection in asymptomatic patients, highlighting a novel prognostic biomarker and potential therapeutic target.