Mutant sporozoites show impaired motility and reduced speed. The prepatency period was prolonged by one day when mutant sporozoites were injected by mosquito bite or subcutaneously. No delay in blood stage infection was observed when sporozoites were injected intravenously.

Sporozoites showed normal gliding motility.Sporozoites showed a twofold decrease in infectivity compared with wild type after infection of mice by intravenous injection. The sporozoites showed a 20-fold decrease in infectivity when mice were infected by intradermal inoculation.The level of HepG2 invasion in vitro of mutant sporozoites was similar to wild type sporozoites and invaded parasites developed efficiently into mature schizonts. In vitro migration/cell traversal assays using Hepa 16 cells and mouse dermal fibroblasts (MDFs) showed a twofold reduction in the migratory activity of sporozoites compared with wild type. Treatment with the cysteine protease inhibitor E-64d, which prevents invasion and results in maximally migratory sporozoites, increased the cell traversal activity but not to the level that was observed with wild type sporozoites.

Normal numbers of midgut (oocyst-derived) and salivary gland sporozoites are produced. Sporozoites showed normal gliding motility, albeit at a lower frequency. Sporozoites showed full in vitro and in vivo infectivity in cultured hepatoma cells and when injected intravenously into rats, respectively.

The prepatency period was prolonged by one day when mutant sporozoites were injected by mosquito bite or subcutaneously. No delay in blood stage infection was observed when sporozoites were injected intravenously.

Sporozoites showed full in vitro and in vivo infectivity in cultured hepatoma cells and when injected intravenously into rats, respectively.

Sporozoites showed a twofold decrease in infectivity compared with wild type after infection of mice by intravenous injection. The sporozoites showed a 20-fold decrease in infectivity when mice were infected by intradermal inoculation.The level of HepG2 invasion in vitro of mutant sporozoites was similar to wild type sporozoites and invaded parasites developed efficiently into mature schizonts. In vitro migration/cell traversal assays using Hepa 16 cells and mouse dermal fibroblasts (MDFs) showed a twofold reduction in the migratory activity of sporozoites compared with wild type. Treatment with the cysteine protease inhibitor E-64d, which prevents invasion and results in maximally migratory sporozoites, increased the cell traversal activity but not to the level that was observed with wild type sporozoites.