Expression and secretion of the Giardia duodenalis variant surface protein 9B10A by transfected trophozoites causes damage to epithelial cell monolayers mediated by protease activity.

Giardia duodenalis is the protozoan parasite responsible for most cases of parasitic diarrhea worldwide. The pathogenic mechanisms of giardiasis have not yet been fully characterized. In this context parasite's excretory/secretory products have been related to the damage induced by the parasite on enterocytes.