Study on the Induction of Immunity by Purified Cysteine Protease against Plasmodium berghei Infected Mice

This study was aimed at inducing immunity against Plasmodium berghei infection using cysteine protease in mice. Twenty laboratory mice were used for the study, they were grouped into 4 groups of 5 mice each. The first and second groups were immunized with 100 µg/l and 50 µg/l of purified cysteine protease respectively; the third group was administered with adjuvant which served as positive control while the fourth group (negative control) was not administered. All the groups were challenged with the parasite Plasmodium berghei. Results for percentage parasitaemia, Packed Cell Volume, Total Protein and Enzyme assay was recorded. Findings revealed that the mice immunized with the higher concentration of the cysteine protease had the lowest load of infection. The mice that were not immunized had the highest load of infection which showed that the cysteine protease conferred protection against infection.