Monoclonal antibody (mAb) sequences were identified from single plasmablasts of DENV-infected patient 013 and patient 020, as previously described (Zanini et al., 2018). The patient from which corresponding mAb sequences were identified is listed in the first column, followed by mAb clonal family ID, mAb name, and gene usage, % nucleotide (nt) somatic hypermutation, and CDR3 amino acid (aa) length for the variable heavy (VH) and light (VL) chain genes. VH and VL sequences were cloned into IgG1 expression vectors and transfected into mammalian cells. Neat crude IgG1-containing culture supernatant was tested for binding to recombinant DENV2 recombinant soluble E protein (rE) and DENV2 reporter virus particles (RVP) by ELISA, and for neutralizing activity against the indicated related flavivirus RVPs. Antibodies 3H5-1 (2 µg/mL), EDE2 B7(2 µg/mL) and EDE1 C10 (10 µg/mL), and CR4354 (2 µg/mL) were used as controls. Antibody binding activity is expressed as fold-change in absorbance values over negative control wells containing media only. The heatmap (light to dark blue) indicates strength of binding, as defined in the key below the table. A value of 1 indicates no increase in binding relative to negative control wells. Percent neutralization was calculated using the formula: (% infection in the absence of IgG1 - % infection in the presence of IgG1) / (% infection in the absence of IgG1) x 100. The heatmap (yellow to red) indicates the range of neutralization potencies as indicated in the key below the table. Results are representative of 2 independent experiments. Under the crude IgG column, a value of <0.0005 indicates undetectable levels of IgG1 in crude culture supernatant. Antibodies selected for further characterization are shown in bold. ‘n/a,’ not applicable; ‘nc,’ not successfully cloned; ‘nd,’ not determined.