IL4 and infection: On day 14 post-infection period, the immunized mice with rGP19 (both 50 μg and 100 μg combined with Montanide adjuvant) and later infected with E. canis showed significantly up-regulated expression of IFNG (p < 0.01), IL1a (p < 0.01), and IL4 (p < 0.05) compared with naive mice on day 14 post-infection, as shown in Figure 4.