Fig 9.

GII.4-1987 mouse polyclonal serum blockade. (A) GII.4-1987 polyclonal mouse sera was diluted 1:1,000 and assayed by EIA for reactivity with GII.4-1987, GII.4-2006, and GII.4-2006(+87A.1) VLPs. Bars represent the mean optical density values with standard errors of the means. The dashed line represents 3 times the background level of binding and indicates a positive signal. (B) GII.4-1987 polyclonal mouse serum blockade of GII.4 VLP/synthetic HBGA interactions. Ability of GII.4-1987 polyclonal mouse sera to block VLP/synthetic CHO was measured by surrogate neutralization assay and expressed as a percentage of the control binding (100%). An antibody is considered a “blocking antibody” if it is able to block at least 50% of the control (dashed line). Anything below the dashed line represents potential neutralization. Error bars represent standard errors of the means from experiments run in triplicate. (C) GII.4-1987 polyclonal mouse serum BT₅₀ values for GII.4-1987, GII.4-2006, and GII.4-2006(+87A.1). Blocking titers of GII.4-1987 mouse polyclonal sera were determined as the serum concentration at which 50% of the VLP/synthetic HBGA was blocked. Box and whiskers plots represent the mean serum concentration at which BT₅₀ was achieved for each VLP.