In general, we found that the pattern of antigenicity when immunizing with FV2 was similar to immunizations with single domains (Figure 4 ). In rats, FV2 antibodies targeted all DBLdomains with similar reactivity, with exception of DBL5e and DBL2x, which showed highest and lowest reactivity, respectively. The levels of reactivity were more or less in line with the reactivity against the native protein of single-domain specific antibodies ( Figure 2B ). In rabbits, the reactivity against the domains appeared to be overall lower than for rats. Furthermore, the rabbit-FV2 reactivity was more focused towards DBL5e and DBL6e, as was also the case for the reactivity of single-domain specific antibodies towards the native erythrocyte surface exposed protein ( Figure 2C ). In summary, it appeared that the pattern of antigenicity found when immunizing with single domains was essentially similar to immunizations with the FV2 protein in the different animals.