title: Virulence of Giardia lamblia: an in vitro study on host-parasite interaction.
abstract: Trophozoites of G. lamblia, a human parasite, were lysed by polymorphonuclear leukocytes (PMNL) of healthy individuals during in vitro interaction. However, the parasite damaged PMNL of giardiasis patients. A prior treatment of giardia trophozoites with anti-giardia serum, caused agglutination of pathogen and, thereby, the cytotoxic capacity of the parasite was reduced. Interaction of giardia-trophozoites with peritoneal macrophage, derived from infected mouse, reduced the phagocytic activity of the latter to 43% (against 100% in control). Macrophage activity was, however, stimulated to 131% when the mice were immunized with giardia antigen prior to experimental infection. Giardia extract proved cytotoxic at a dose of 0.7 mg, to HeLa cells in tissue culture. These in vitro studies offer experimental evidence of the cytotoxic and immuno-toxic behaviour of G. lamblia towards the host cells.
authors.forename: N
authors.initials: N
authors.lastname: Gupta
authors.forename: A K
authors.initials: AK
authors.lastname: Agarwal
authors.forename: S K
authors.initials: SK
authors.lastname: Katiyar
authors.forename: K
authors.initials: K
authors.lastname: Chandra
authors.forename: A
authors.initials: A
authors.lastname: Sharma
authors.forename: A K
authors.initials: AK
authors.lastname: Rastogi
authors.forename: S R
authors.initials: SR
authors.lastname: Das
mesh_terms: D000818:Animals; D005872:Giardia / Q000472:pathogenicity*; D005873:Giardiasis / Q000276:immunology / Q000469:parasitology; D006367:HeLa Cells; D006790:Host-Parasite Interactions; D006801:Humans; D008264:Macrophages / Q000276:immunology / Q000502:physiology*; D051379:Mice; D009504:Neutrophils / Q000276:immunology / Q000502:physiology*; D014774:Virulence