Peritoneal macrophage response from mice infected with P. y 17XL or 17XNL to pRBC lysate. Three days after mice were treated with thioglycollate, peritoneal macrophages were isolated from mice on one, three and five days after intraperitoneally injected with 2 × 105 nRBCs (N), 2 × 105 P. yoelii 17XNL- or 17XL-infected RBCs. Each 1 × 106 macrophages from mice infected with P. yoelii 17XNL were stimulated with medium (M), 1 × 107 P. yoelii 17XNL-infected RBCs lysate for 24 h, and supernatants were collected to detect TNF-α (A) and IL-6 (C). Each 1 × 106 macrophages from mice infected with P. yoelii 17XL were also stimulated with medium (M), 1 × 107 P. yoelii 17XL-infected RBCs lysate for 24 h, and supernatants were collected to detect TNF-α (B) and IL-6 (D). Three individual experiments were performed, and all data are presented as the mean ± SD (*P <0.05, **P <0.01).