Antibody titers in outbred mice immunized with DNA vaccines expressing native or synthetic EBA-175 RII or MSP142. ELISA results are reported as the interpolated reciprocal dilution estimated to give an optical density of 0.5. Group sizes were as follows: for pSRII and pNRII, 10 ICR mice/group; for pSMSP-142 and pNMSP-142, 8 CD-1 mice/group, except for 50-μg pNMSP-142, which had 6 mice. Bars represent geometric mean titers, and solid circles represent individual responses.