Fig 1. Schematic of humanized mice and their utility to model human malaria parasite life cycle stages.

The different stages of the life cycle of the parasites in the human host are illustrated in the center. The lines surrounding it indicate the extent of the cycle covered by each humanized mouse model, color coded to represent the parts of the cycle covered as follows: from mosquito delivery of sporozoites into the skin to release of exo-erythrocytic merozoites from liver (green, FRG and SCID-Alb-uPA); from mosquito delivery of sporozoites into the skin to erythrocyte invasion (blue, FRG-NOD); from mosquito delivery of sporozoites into the skin to sexual stages (purple, TKG-NOG and ACF8); and from erythrocyte invasion to sexual stages (orange, NSG, NRG and NOG). Filled mice indicate models with available data for that part of the cycle, whereas outlined mice indicate models with proposed roles in the corresponding part of the cycle. Mice shown in Green, Blue and purple have been demonstrated to support repopulation with human hepatocytes. Models depicted in purple and orange have been shown to support long-term maintenance of human erythrocytes. The FRG-NOD mouse can support short term repopulation with human erythrocytes, although to our knowledge long term studies have not been attempted.