FIG. 2.

IgG subclass of antibodies to native P. yoelii MSP1 in mice immunized with GST-MSP1₃₃ or -MSP1₁₉, as measured by IFAT. Sera from C57BL/6 and BALB/c mice immunized three times with either GST-MSP1₃₃ or -MSP1₁₉ were analyzed by IFAT for reactivity with mouse RBC infected with P. yoelii YM. IFAT reactivity for all four IgG subclasses was measured and is shown as titers, with different bar patterns representing different subclasses. One of the GST-MSP1₁₉-immunized BALB/c mice had an IgG1 titer in excess of 100,000 (262,000). IgG3 was only detected in BALB/c mice immunized with GST-MSP1₃₃. C indicates mice that cleared their infection; the number in parentheses indicates the day on which the infection was cleared. † indicates mice that died or were humanely killed, with the day of death in parentheses. Percentages indicate the highest parasitemia detected during the course of infection.