Immunological aspects of Giardia infections
نویسنده
چکیده
Immunodeficiency, particularly antibody deficiency, predisposes to increased intensity and persistence of Giardia infections. Giardia-infected immunocompetent hosts produce serum and intestinal antibodies against Giardia trophozoites. The number of Giardia muris trophozoites, in mice with G. muris infection, is reduced by intra-duodenal administration of anti-G. muris antibody. Giardia intestinalis antigens that are recognised by human anti-trophozoite antibodies include variable (variant-specific) and invariant proteins. Nitric oxide (NO) appears to contribute to host clearance of Giardia trophozoites. Arginine is a precursor of NO and is metabolised by Giardia trophozoites, possibly reducing its availability for generation of NO by the host. Work with mice suggests that T lymphocytes and interleukin-6 (IL-6) contribute to clearance of Giardia infection via mechanisms independent of antibodies.
منابع مشابه
Common variable immunodeficiency and isosporiasis: first report case.
We report a severe case of diarrhea in a 62-year-old female HIV-negative patient from whom Giardia lamblia and Isospora belli were isolated. Because unusual and opportunistic infections should be considered as criteria for further analysis of immunological status, laboratory investigations led to a diagnosis of common variable immunodeficiency (CVID). This is the first reported case of isospori...
متن کاملBiology of Select Zoonotic Protozoan Infections of Domestic Animals
In this overview, the basic biology of select protozoan parasites of veterinary importance was covered. These include the Apicomplexans, Eimeria, Theileria, Cryptosporidium, and the Flagellates Giardia and African trypanosomes. Available information was synthesized into a relatively simple information guide of potential interest to a wide reading audience. Where appropriate, references are made...
متن کاملGiardiasis: Modern Concepts in Control and Management
Giardia is the most common enteric protozoan pathogen of humans, domestic animals and wildlife. Children are at the most risk from the clinical consequences of Giardia infection, particularly those in developing countries and living in disadvantaged community settings. Molecular epidemiological studies have helped to elucidate sources of infection and the public health significance of animal re...
متن کاملNew finding of Giardia intestinalis (Eukaryote, Metamonad) in Old World archaeological site using immunofluorescence and enzyme-linked immunosorbent assays.
In this study, nine organic sediment samples from a medieval archaeological site at Pineuilh, France, were examined for Giardia intestinalis using two commercially available immunological kits [enzyme-linked immuno sorbent and immunofluorescence (IFA) assays]. Both techniques detected G. intestinalis in one sample, dated to 1,000 Anno Domini. This is the first time IFA was successfully used to ...
متن کاملMicrobes and microbial toxins: paradigms for microbial-mucosal interactions I. Pathophysiological aspects of enteric infections with the lumen-dwelling protozoan pathogen Giardia lamblia.
Giardia lamblia is one of the most important causes of waterborne diarrheal disease worldwide, and giardiasis is the most common protozoan infection of the human small intestine. Symptomatic infection is characterized by diarrhea, abdominal pain, and malabsorption, leading to malnutrition and weight loss, particularly in children. The pathogen resides strictly in the lumen of the small intestin...
متن کامل