Fig. 4: Surface expression of VAR2CSA is required for in vivo adaptation.
a RBC-NSG mice were infected with 3D7attB AS pMG56 parasites and were either given aTc or PBS. When parasitemia reached 5%, in vivo IVIS imaging to detect luminescence was performed. Data shown are mean ± SEM, n = 3 biologically independent animals. *p < 0.03, One-way ANOVA with Tukey’s multiple comparisons. b Western blot of HA in NF54CR AS mahrp1 with or without aTc treatment. Two independent repeats gave similar results. c Immunofluorescent assay of NF54CR AS mahrp1 parasites cultured with or without aTc. Parasites were probed with anti-PfEMP1 (red), anti-HA (green) and DAPI (blue). Scale bar  =  5 μm. Two independent repeats gave similar results. d Parasitemia of RBC-NSG mice infected with NF54CR AS mahrp1 with (solid) or without (dash) aTc treatment. Parasitemia was assessed by peripheral blood smear with Giemsa staining. Shown are mean parasitemia ± SEM, n = 3 biologically independent animals. *p = 0.003 (Day 10), *p = 0.009 (Day 14), Multiple T test with Holm-Sidak correction. e Comparison of macrophage phagocytosis of NF54CR, NF54CR AS, NF54CR AS mahrp1 with and without aTc treatment of parasites. Data shown are mean ± SEM, n = 4 biologically independent samples (n = 3 biologically independent samples for NF54CR AS). *p < 0.02, ***p = 0.007, ****p < 0.0001. One-way ANOVA with Tukey’s multiple comparisons. f Percentages F4/80hi CD11bint macrophages quantified by flow cytometry in the spleen of RBC-NSG mice given PBS or chlodronate liposone. Data shown are mean ± SEM, n = 3 biologically independent animals, two-tailed t test, **p = 0.0039. g Parasitemia of RBC-NSG mice infected with 3D7attB in clodronate-treated mice and control mice treated with PBS-liposome. Parasitemia was assessed by peripheral blood smear with Giemsa staining. Data shown are mean ± SEM, n = 3 biologically independent animals. *p = 0.0029 (Day 3), *p < 0.0001 (Day 5), *p < 0.0001 (Day 7). Source data are provided as a Source Data file.
