Cotugno N, Ruggiero A, Bonfante F, Petrara MR, Zicari S, Pascucci GR, Zangari P, De Ioris MA, Santilli V, Manno EC, Amodio D, Bortolami A, Pagliari M, Concato C, Linardos G, Campana A, Donà D, Giaquinto C, CACTUS Study Team , Brodin P, Rossi P, De Rossi A, Palma P
Cell Rep 34 (11) 108852 [2021-03-16; online 2021-03-18]
As the global COVID-19 pandemic progresses, it is paramount to gain knowledge on adaptive immunity to SARS-CoV-2 in children to define immune correlates of protection upon immunization or infection. We analyzed anti-SARS-CoV-2 antibodies and their neutralizing activity (PRNT) in 66 COVID-19-infected children at 7 (±2) days after symptom onset. Individuals with specific humoral responses presented faster virus clearance and lower viral load associated with a reduced in vitro infectivity. We demonstrated that the frequencies of SARS-CoV-2-specific CD4 +CD40L+ T cells and Spike-specific B cells were associated with the anti-SARS-CoV-2 antibodies and the magnitude of neutralizing activity. The plasma proteome confirmed the association between cellular and humoral SARS-CoV-2 immunity, and PRNT+ patients show higher viral signal transduction molecules (SLAMF1, CD244, CLEC4G). This work sheds lights on cellular and humoral anti-SARS-CoV-2 responses in children, which may drive future vaccination trial endpoints and quarantine measures policies.