A panel of 505 antigen-antibody combinations was analyzed using discriminant function analysis, as described in the Methods. (A) The top 4 antibody-antigen (Ab-Ag) combinations are presented (from top left to right: subtype C T/F BF1266 gp140 IgG3, subtype C CH505 T/F IgG4 avidity, subtype B SC42261 gp140 IgG4 avidity, and gp41 ID IgG avidity). Y-axis values for the gp41 ID epitope avidity score represent the net difference of MFI (CIT) – MFI (PBS). (B) The canonical score (i.e., latent variable representing the combination of measurements in A) for the solution with the top 4 Ab-Ag combinations. CIT, Na-citrate, pH 4.0.