Fig. 4
Heterologous immunization with a high-dose RAS booster in C57BL/6 mice can be used to distinguish between recalled and non-recalled responses. Antigen-specific responses in C57BL/6 mice immunized once with 8 × 104 P. berghei RAS (PbRAS), homologously with 1 × 104 P. berghei RAS followed by 8 × 104 P. berghei RAS (PbRAS → PbRAS) or heterologously with 1 × 104 P. yoelii RAS followed by 8 × 104 P. berghei RAS (PyRAS → PbRAS). Antigens included PbTRAP (a), PbS20 (b), PbGAP50 (c), PbF4 (c) and PbNCY (e); additional identifying details are in Fig. 1 and “Methods” section. Bars display mean value and error bars show the 95 % confidence interval; *p < 0.05, **p < 0.01, ***p < 0.001, ****p < 0.0001, Student’s t-test