title: Amebic cysteine proteinase 2 (EhCP2) plays either a minor or no role in tissue damage in acute experimental amebic liver abscess in hamsters.
abstract: Amebic cysteine protease 2 (EhCP2) was purified from ethyl ether extracts of axenically grown trophozoites of Entamoeba histolytica strain HM1-IMSS. The purification procedure involved molecular filtration and electroelution. Sequence analysis of the purified product revealed EhCP2 and ubiquitin(s). Electrophoretic migration patterns, isoelectric point determination and Western blot studies failed to reveal other EhCP molecules. Polyclonal antibodies against the purified EhCP2 prepared in rabbits either stabilized or enhanced the enzyme activity in a dose-response manner. Purified EhCP2 was enclosed within inert resin microspheres (22-44 microm in diameter) and injected into the portal vein of normal hamsters. In the liver, the microspheres caused mild acute inflammation and occasional minimal necrosis of short duration. Sections of the liver were immunohistochemically stained with the anti-EhCP2 antibody and the microspheres were positive for only a very short period (1 h) after injection. Sections of experimental acute (1 day, 5 days) amebic liver abscess produced in hamsters were also stained with the anti-EhCP2 antibody; and amebas were intensely positive but no staining was observed at any time in the surrounding necrotic structures. It is suggested that EhCP2 plays either a minor or no role in the causation of tissue damage in experimental acute liver amebiasis.
authors.affiliation: Department of Experimental Medicine, National University of México Medical School, Ciudad Universitaria, Apartado Postal 70641, 04510 México, Districto Federal, México.
authors.forename: Alfonso
authors.initials: A
authors.lastname: Olivos-García
authors.forename: Augusto
authors.initials: A
authors.lastname: González-Canto
authors.forename: Rosario
authors.initials: R
authors.lastname: López-Vancell
authors.forename: Maria del Carmen
authors.initials: Mdel C
authors.lastname: García de León
authors.forename: Eusebio
authors.initials: E
authors.lastname: Tello
authors.forename: Mario
authors.initials: M
authors.lastname: Nequiz-Avendaño
authors.forename: Irmgard
authors.initials: I
authors.lastname: Montfort
authors.forename: Ruy
authors.initials: R
authors.lastname: Pérez-Tamayo
mesh_terms: D000208:Acute Disease; D000818:Animals; D006224:Cricetinae; D003546:Cysteine Endopeptidases / Q000302:isolation & purification / Q000378:metabolism*; D004748:Entamoeba histolytica / Q000201:enzymology / Q000472:pathogenicity*; D004749:Entamoebiasis / Q000469:parasitology / Q000473:pathology*; D008099:Liver / Q000201:enzymology / Q000473:pathology; D008101:Liver Abscess, Amebic / Q000469:parasitology / Q000473:pathology*; D011817:Rabbits
chemical_list: D003546:Cysteine Endopeptidases