Intranasal DeltavicK Infection Induces SeM-Specific Mucosal IgA and Systemic IgG 
To examine the humoral immune responses in the intranasal DeltavicK infection, nasal wash and serum samples were collected from the 8 mice infected intranasally with DeltavicK and 3 surviving mice infected with the wild-type S. equi 30 days after infection.
Half of the nasal wash samples from the mice infected with DeltavicK had similar levels of SeM38-260-IgA reactivity with those from the mice infected with the wild-type strains.
Similarly, these 4 mice with higher IgA levels also had higher levels of SeM-specific systemic IgG (Fig. 5B).
Western blotting analysis was used to confirm the presence of SeM-specific IgG.
The wild-type sera and 5 of the 8 DeltavicK samples had strong immunoreactions with SeM38-260 in Western blotting analysis (Fig. 5C).
Thus, the DeltavicK mutant has the ability to induce mucosal and systemic immune responses, though there was host variation in these responses caused by DeltavicK infection.
