Background: Opisthorchiasis caused by Opisthorchis viverrini, is of considerable public health importance in Southeast Asia, particularly in Lao People’s Democratic Republic and Thailand. The infection is associated with a number of hepatobiliary diseases including cholangitis, obstructive jaundice, hepatomegaly, cholecystitis, cholelithiasis and cholangiocarcinoma.
Objective: This study aims to localize the expression sites of O. viverrini tubulin using immunohistochemistry by monoclonal
anti α-tubulin (MAαT) and anti β-tubulin (MAβT).
Material and Method: The adult worms of O. viverrini, and the adult worm of O. viverrini in biliary system of hamsters were
fixed, cryo-sectioned and then immunohistochemically stained. The sections were incubated with MAαT or MAβT. A positive
test required the observation of brown-staining in the fluke’s organs.
Results: The immunohistochemistry of MAαT and MAβT in adult worms of O. viverrini, and the adult worm of O. viverrini
in biliary system of hamsters strongly expresses in the sperm and seminal vesicles of the worm. MAαT and MAβT expressed
slightly in sub-tegumental tissue, stromal parenchyma, muscle fibers, and miracidium in the mature egg of the worm. No staining in the spermatogonia, gut epithelium, immature egg, tegument or vitelline glands of the worm nor in the hamster bile duct epithelium was seen.
Conclusion: The present study indicates that O. viverrini tubulin is present in the reproductive organs and other important
organs of the worm. Because it plays a key role in the biological processes of cellular motility and fertility it should be further
studied in detail including the characterization, production of recombinant proteases, and their application in immunodiagnosis.

Keywords: Localization-Tubulin-Carcinogenic human liver fluke-Opisthorchis viverrini