Fig. 1

Protective humoral immunity in SARS-CoV-2 infected pediatric patients. a Humoral immune response mediated by circulating immunoglobulin (GO:0002925); b Percentage of IgG+ B cells in CD19+ B cells and CD27+ memory B cells. The statistical method is the Student’s t test. c Antibodies detection for nucleocapsid protein and receptor binding domain of Spike of SARS-CoV-2. +: positive, −: negative; (+−): weak negative. d Receptor-blocking activity of serum from an infected case and uninfected control. e Pseudovirus neutralizing assay of serum from an infected case and uninfected control. The statistical method is the Student’s t test