Culturing Plasmodium falciparum and Plasmodium berghei

Plasmodium falciparum 3D7 (American Type Culture Collection, ATCC PRA-405D) and P. falciparum FCR3 (American Type Culture Collection, ATCC® 30932) were purchased from the ATCC (Manassas, USA). The chloroquine-susceptible strain Plasmodium berghei NK65 (MRA-268) and the atovaquone-resistant strain P. berghei NAT (MRA-415) were purchased from Bei Resources (Manassas, USA). The P. falciparum strains 3D7 and FCR3 were grown in human erythrocytes as previously described [27 (link)]. Briefly, parasites were maintained in continuous culture with 5% haematocrit of type O human red blood cells suspended in Roswell Park Memorial Institute (RPMI) 1640 medium supplemented with 24 mM NaHCO₃, 25 mM HEPES, 0.8% hypoxanthine, 0.9% Albumax, and 25 μg/mL of gentamicin. The 6-well plates were placed in an incubator (atmosphere: 5% CO₂, 5% O₂, and 90% N₂) at 37 °C and the medium was changed daily when the level of parasitaemia was at least 5%. The parasite density was determined by Giemsa staining of thin smears and expressed as a percentage of infected erythrocytes in a field of a total of 500 erythrocytes.