Fig. 3.

Anti-OVA antibody elicited by administration of pcDNA-sTGFβR/huIg in mice. Mice with or without challenged tumors received pcDNA-sTGFβR/huIg or pcDNA3.1 twice through different routes at a 2-week interval. Similarly, OVA protein (pOVA) was injected twice subcutaneously with a 2-week interval. One week after the last injection, the mice were bled and their sera were tested by ELISA for reactivity with OVA. The absorbance at a dilution of 1:40 was plotted in each group (a). Both anti-OVA IgM and IgG were detected by this assay in which antimouse immunoglobulin was used as secondary antibody. *P<0.001; **P=0.0054. The sera shown in a were examined for the reactivity of IgG with OVA (b). *P<0.05