Schistosomiasis, the most important parasitic disease in Egypt, has plagued its people since
ancient times. Two species of Biomphalaria are reported from Egypt, the indigenous
Biomphalaria alexandrina and Biomphalaria glabrata, the latter is believed to be introduced
during the past few decades. Both are known to be excellent hosts of Schistosoma mansoni, in
Egypt. SDS-PAGE was used to separate tissue proteins of control and Schistosoma-infected
Biomphalaria alexandrina and B.glabrata snails. Also total protein of these groups was
measured using Bradford assay method. The present data showed that there is a variation in the
protein profiles under the effect of infection, and the days of infections can also affect total and
protein profiles pattern. There was a significant decrease in B.alexandrina total protein, in
contrary, total protein of B.glabrata groups exhibited significant and insignificant increase under
the effect of infection. The electrophoretic pattern showed that there is an interspecific variation
between B.alexandrina and B. glabrata control (non-infected) and infected ones. Protein profiles
showed 13 bands ranged between 15-300 KDa, with a unique bands to some groups. The
similarity indices showed the high value (0.8) between the two Biomphalarian species.
This study is an attempt to specifiy characterization of similar species of animals using modern
simple technique rather than morphological old methods, and further detects the variable protein
bands due to infection with S.mansoni.