Figure 2.

Lectin fingerprints reveal neutralizing potential of prevaccinated patient antibodies and patient-derived sera. (A) Host infection by SARS-CoV-2 elicits a rapid humoral response producing either neutralizing or non-neutralizing antibodies. (B) Competitive ELLA assay to reveal unique lectin fingerprints. (C) Log (fold change) upon treatment of immobilized RBD (gray) and FL-Spike (blue) containing 24 plant and fungal lectins with MM43 commercial anti-RBD antibody (1 μg/mL) in parallel. (D) Patient sera metadata table used in blinded study (n = 8) indicating seropositivity and estimated RBD abundance. Serum dilution in pseudovirus inhibition assay performed with pseudotyped virus indicates competitive ID₅₀ values. (E) Dendrogram displaying hierarchical clustering analysis of immobilized RBD with bound plant, fungal, and prokaryotic lectins (1 μg/mL) treated with convalescent patient sera (1:100 dilution). Distinct and separate lectin fingerprints were observed for each sample class. Dendrograms from neutralizing serum (rows 1 and 2, n = 2) and non-neutralizing (rows 3–6, n = 4). Hierarchical analysis represents data from two separate experiments.