3.3 VSV/RABV-GP induces a T helper cell type-2 (Th2) immune bias
To determine whether Th1 and/or Th2 humoral response was induced by vaccination with VSV/RABV-GP, the levels of specific IgG1 and IgG2a subclasses were compared with the inactivated RABV vaccine. Sera samples showed statistically indistinguishable GP-specific IgG1 and IgG2a responses (Figure 3A and B). Analysis of the antigen-specific IgG1/IgG2a ratio in the sera samples revealed that mice immunized with VSV/RABV-GP had a greater IgG1/IgG2a than the inactivated RABV (Figure 3C). The data indicate that VSV/RABA-GP induces a Th2-biased immune response.