Fig. 10. CD81 and cholesterol are required for P. falciparum sporozoite invasion of human hepatocytes. (A) Primary human hepatocytes transfected with a siRNA oligonucleotide targeting CD81 (siCD81) or with a control siRNA (cont) were stained with anti-CD81 (mAb TS81, left panel) or anti-CD9 (mAb TS9, right panel) and analyzed by flow cytometry. (B) Quantification of P. falciparum exo-erythrocytic forms (EEFs; mean of triplicate wells ± s.d.) in human hepatocytes transfected with siRNA oligonucleotides targeting CD81 (siCD81) or CD9 (siCD9), or with a control siRNA (control). ^*P<0.05 as compared to control. (C) Primary human hepatocytes were treated with MßCD followed by MßCD/cholesterol, when indicated, before infection by P. falciparum sporozoites. The number of EEF-infected cells was determined as described in the Materials and Methods section. ^**P<0.01, as compared to untreated control.