IL4 and infection: Considering that IFN-γ (Th1 cytokine) and IL-4 (Th2 cytokine) are known to induce isotype switching to IgG2a and IgG1, respectively23,24, and IgG2a antibodies are associated with protection from parasitic infections25,26, these data suggest that nano2/4 enhances the antibody switch to protective isotype against Tc infection in both pregnant and non-pregnant mice.