UA signals for enhanced tumor-specific IgG1 antibodies. (A) The tumor-specific antibody concentration in the serum 14 days after 2 injections of dying tumor cells alone (T), tumor cells with UA (T + UA) or with UA alone (UA). Each bar represents the mean (± SEM) of 12 replicates calculated from the optical densities (× 1000) in the ELISA assay. Similar to panel A, panels B and C show the levels of IgG1 and IgG2a, respectively. Each mean (± SEM) is calculated from 2 to 7 replicates. (D) The mean fluorescent intensity (MFI) of tumor cells stained with IgG from sera of animals. Each bar represents the mean (± SEM) of 3 replicates; *P = .05. (E) Rat neu-specific IgG levels in animals treated as determined by capture sandwich ELISA. Each bar is the mean (± SEM) of 3 determinations. (F) Western immunoblot analysis of rat neu immunoprecipitated with sera. Numbers shown are the position of the molecular weight markers (KDa). (G-I) The serum levels of total IgG (F), IgG1 (G), and IgG2a (H) specific for ovalbumin from control mice (Cont), ovalbumin-immunized (Oval), or OVAL/UA-immunized (Oval + UA) mice (n = 5-7). The levels of IgG and IgG1 obtained following ovalbumin immunization were not significantly different (P > .05).