1. Differential antibody responses to Giardia lamblia strain variants expressing dissimilar levels of an immunogenic protein
- Author
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Lucila Rascon, Carlos Velazquez, Victor Dominguez, Ramón Enrique Robles-Zepeda, Jael Quintero, Lourdes Valencia, Thania Garzon, and Adriana Garibay-Escobar
- Subjects
0301 basic medicine ,Giardiasis ,Antigenicity ,030231 tropical medicine ,Immunology ,Blotting, Western ,Protozoan Proteins ,Enzyme-Linked Immunosorbent Assay ,medicine.disease_cause ,CD19 ,Microbiology ,03 medical and health sciences ,Mice ,fluids and secretions ,0302 clinical medicine ,Antigen ,parasitic diseases ,medicine ,Giardia lamblia ,Animals ,Mice, Inbred C3H ,biology ,Immunogenicity ,Giardia ,biology.organism_classification ,Intestines ,Agglutination (biology) ,030104 developmental biology ,biology.protein ,Cytokines ,Parasitology ,Antibody - Abstract
AIMS Giardia lamblia is a protozoan parasite that causes giardiasis, one of the most common worldwide gastrointestinal diseases. For rational development of a Giardia vaccine, increasing our understanding of the host-Giardia interaction is crucial. In this study, we analysed the immunogenicity and antigenicity of two G lamblia strain variants [GS and GS-5G8 (+)], which express different levels of the variant-specific surface protein (VSP) 5G8 and also analysed the intestinal histological changes associated with Giardia infection. METHODS AND RESULTS We evaluated the antibody responses induced by G lamblia strains in infected, reinfected and immunized C3H/HeJ mice using ELISA, flow cytometry, Western blotting and histological analysis. Our results showed that G lamblia GS-5G8 (+) was more immunogenic and antigenic than the GS strain. The antibody response against the GS-5G8 (+) strain primarily recognized 5G8 protein. Serum antibody from infected and reinfected mice exhibited specific agglutination of trophozoites in vitro. GS-5G8 (+)-infected mice showed higher CD19+ infiltrating cell levels compared to GS-infected animals. CONCLUSION G lamblia strains with different expression levels of an immunogenic antigen (VSP 5G8) induce differential antibody responses. A better understanding of the immunogenic proteins of G lamblia will contribute to the rational development of an effective vaccine against this parasitic disease.
- Published
- 2020