FIG 9.

In vitro analysis of the humoral immune response of the experimental groups. A colorimetric enzyme-linked immunosorbent assay was used to analyze a 1:100 dilution of serum from the Vetera-, VC2-, and VC2–EHV-1–gD-vaccinated mice and unvaccinated mice for EHV-1-reactive polyclonal IgG1, IgG2a, IgG2b, and IgM produced 8 weeks after the first vaccination (before challenge) and 1 week after challenge. Statistical comparisons were conducted using one-way analysis of variance followed by the Newman-Keuls multiple-comparison test. *, P < 0.05; **, P < 0.01; ***, P < 0.001. OD, optical density.