Fig. 6
Quantification of neutralizing and non-neutralizing antibody titers through indirect ELISA. Cut-off was calculated by multiplying by three the average of blank OD signal derived from six micro-wells containing sample diluents and secondary HRP-antibody. IgG results were calculated by relating the OD value of each specimen to the respective cut-off value of the plate. Samples with ODs below the cut-off value were considered negative and the titer assigned in this case was half of the starting dilution. Samples in which ODs were above the cut-off value were deemed positive and a titer was calculated. Dashed bold black lines indicate medians and dashed thin black lines indicate quartiles.
