Surface antigenic variation in Giardia lamblia

Regulation of antigenic variation in Giardia lamblia.

Antigenic variation, a clonal phenotypic variation developed by microorganisms, involves the permanent switching of homologous, antigenically different cell surface molecules. In pathogenic microorganisms, antigenic variation is often described as a mechanism to evade the host immune system and therefore is responsible for the generation of chronic and/or recurrent infections. However, antigeni...

Antigenic variation of Giardia lamblia in vivo.

A single Giardia lamblia trophozoite can give rise in vitro to G. lamblia with varying surface antigens. To determine whether antigenic variation also occurs in vivo, gerbils were inoculated with defined G. lamblia clones and the surface antigens of the intestinal trophozoites were studied at different times during the infection. The proportion of monoclonal antibody 6E7-reacting trophozoites f...

Antigenic variation of a cysteine-rich protein in Giardia lamblia

The WB isolate of Giardia lamblia expresses a cysteine-rich 170-kD surface antigen (CRP170) that undergoes antigenic variation. An (6E7), cytotoxic for isolates expressing CRP170, was used in another study to select antigenic variants from clones of the WB isolate of Giardia. CRP170 was replaced by surface-labeled bands ranging in size from approximately 50 to 170 kD. In this study, mAb 6E7 was...

Giardia Lamblia.

Detection of Giardia lamblia Cysts in Surface Waters of Rasht City, Iran

Introduction: Giardia lamblia is a protozoan parasite with universal distribution in human populations. This infections transfer to human via contaminated foods and waters with Giardia cysts. The Knowledge on the incidence of this agent in the potential infection sources can provide valuable information for control and the spread of this parasite to human communities. This study was aimed to is...