Comparative studies on the biochemical composition and polypeptide profiles of the cyst walls from sterile and fertile hydatid cysts of Echinococcus granulosus from buffalo host

In the present study, biochemical composition and polypeptide profiles of the cyst walls of sterile and fertile hydatid cyst, collected from the lungs of naturally infected Bubalus bubalis have been investigated. Significant quantitative differences in various biochemical components as well as in protein banding patterns were observed between the two types of cyst walls, suggesting variations in their metabolic states. The cyst wall collected from fertile cysts had significantly less glycogen, lipids and triglycerides but more RNA and DNA as compared to sterile cyst wall. Among phospholipid fractions, lysophosphatidylethanolamine and phosphatidylethanolamine were significantly higher in the fertile, whereas, sphingomyelin showed higher values in the sterile cyst wall. The numbers of polypeptides resolved in the fertile cyst wall were more than those in sterile cyst wall possibly due to the presence of extra proteins required for production of brood capsules and protoscoleces. Detection of more polypeptides by silver than CBBR-250 staining could be due to high sensitivity of silver stain which also detects conjugated proteins such as lipo-, phospho- and glycoproteins. The characteristic polypeptides specific to either types of the cyst wall have the potential to be exploited for diagnostics.