FIG. 4.
Individual anti-Env IgG titer raised by DNAs expressing sgp120 fused to murine C3d. (A) 3. Mice were primed with DNA at day 0 and boosted at weeks 6, 12, and 18. Sera, collected at week 20, were assayed by ELISA for specific IgG, and the endpoint dilution titer was determined. (B) Mice were primed with DNA at days 0 and 6 and then boosted with sgp120IIIB at weeks 12 and 18. Then, 96-well plates were coated with recombinant gp120 protein-derived CHO cells expressing the HIV-1 isolate, IIIB. Each datum point represents the endpoint dilution titer for an individual mouse. Preimmune sera from mice had no detectable specific IgG. Endpoint dilution titers were conducted by diluting the sera until the OD values reached background levels. The horizontal line in each lane represents the averaged titer for that group. Other symbols for panels A and B are as defined in the legend to Fig. 3.