Impact of cysteine protease inhibitor on infection of biomphalaria Alexandria with schistosoma mansoni and evaluation of protease activity in snail's haemolymph

ABSTRACT

This work aimed to study the effect of cysteine protease inhibitor on Schistosoma mansoni miracidia and their host Biomphalaria Alexandrina snails. The survival of miracidia decreased steadily with the increase in inhibitor concentration and the rising in their mortality was observed by increasing the inhibitor concentration up to 100 micro/ml. Exposure of snails to two concentrations of the cysteine protease inhibitor25 and 50 micro g/ml during miracidial exposure, reduced infection rate of the snails in the two groups 13.3% and 12.5%, respectively in comparison with its control group being 73.0%, Continuous exposure of the two concentrations of cysteine proteuse inhibitor in the two sizes [3 +/- 1mm] and [6 +/- 1mm], reduced infection rate being 3.03% and 5.5%, respectively. The control group of snails size 3 +/- 1mm was more susceptible to infection than that of the large ones [6 +/- mm], the infection rates was 73.0% and 15.6%, respectively. The protease activity in infected experimental groups increased significantly when compared to the un-infected control group [6.13 +/- 4.35] audit was also increased significantly in the one day tested group, compared to the other groups, in the majority of the infected groups