Fig. 2 |. Sequences of anti-SARS-CoV-2 RBD antibodies.

a, Representative flow cytometry plots showing dual AlexaFluor-647–RBD- and PE–RBD-binding B cells for six study individuals (designated COV21, COV47, COV57, COV72, COV96 and COV107) (the gating strategy is shown in Extended Data Fig. 5). The percentage of antigen-specific B cells is indicated. b, As in a. Graph summarizes the percentage of RBD-binding memory B cells in samples obtained at 1.3 and 6.2 months from 21 randomly selected individuals. Red horizontal bars indicate geometric mean values. Statistical significance was determined using two-tailed Wilcoxon matched-pairs signed-rank test. c, Number of somatic nucleotide mutations in the IGVH (top) and IGVL (bottom) genes in antibodies obtained after 1.3 or 6.2 months from the indicated individual (left) or all six donors (right). Statistical significance was determined using two-tailed Mann–Whitney U-tests. Horizontal bars indicate median values. d, Pie charts show the distribution of antibody sequences from six individuals after 1.3¹ (top) or 6.2 months (bottom). The number in the inner circle indicates the number of sequences analysed for the individual denoted above the circle. Pie-slice size is proportional to the number of clonally related sequences. The black outline indicates the frequency of clonally expanded sequences detected in each participant. Coloured slices indicate persisting clones (same IGHV and IGLV genes and highly similar CDR3) found at both time points in the same participant. Grey slices indicate clones unique to the time point. White slices indicate singlets found at both time points, and the remaining white area indicates sequences that were isolated once. e, Graph shows relative clonality at both time points for all six donors. Red horizontal bars indicate mean values. Statistical significance was determined using two-tailed t-test.