Control of Giardiasis by Interleukin-17 in Humans and Mice—Are the Questions All Answered?

Singer, Steven M.

doi:10.1128/cvi.00648-15

Cited by 22 publications

(19 citation statements)

References 37 publications

Supporting

Mentioning

Contrasting

Order By: Relevance

“…Elevated in vitro IL-17 responses have been reported in a cohort of adult travelers returning to Denmark with giardiasis [7] and IL-17 has been shown to be essential for proper control of G. muris and G. lamblia infections in mice [6]. This is the first report of which we are aware showing IL-17 production in children with giardiasis.…”

Section: Discussionmentioning

confidence: 71%

“…The disruption of tight junctions, shortening of microvilli, epithelial permeability and altered intestinal motility have all been observed [5]. Several studies have analyzed cytokines in murine giardiasis, and a consensus has formed on the importance of IL-17 for protective immunity [6]. In adult human patients who recovered from giardiasis, IL-17 was upregulated when effector memory CD4 + T cells were restimulated in vitro with Giardia antigens [7].…”

Section: Introductionmentioning

confidence: 99%

See 1 more Smart Citation

Giardiasis Alters Intestinal Fatty Acid Binding Protein (I-FABP) and Plasma Cytokines Levels in Children in Brazil

et al. 2019

Self Cite

View full text Add to dashboard Cite

Giardiasis is an intestinal infection caused by ingestion of water or food contaminated with cysts of Giardia lamblia. Susceptibility is higher in children and overall prevalence can reach up to 90% in low-income areas, although outbreaks are also reported in developed countries. Both parasite and immune-mediated epithelial damage has been observed in vitro and in animal models. However, whether enterocytes are directly damaged during infection is not entirely known. Our goal was to identify whether plasma levels of intestinal fatty acid binding protein (I-FABP), a marker of enterocyte damage, are related to the immune response in giardiasis. Blood plasma was collected from 31 children (19 Giardia-positive) from a public day care in Rio de Janeiro, Brazil. The levels of I-FABP were increased in Giardia-infected children compared to children without detectable infection. There was no difference in I-FABP levels in giardiasis caused by different genetic assemblages of Giardia. Levels of IL-8 were decreased, while there was a trend to elevated IL-17 in the Giardia-positive children. A positive correlation was observed between I-FABP and IL-17 levels as well as TNF, suggesting that epithelial damage can be related to cytokine production during giardiasis. These results help elucidate the relationship between the disruption of the intestinal mucosal barrier and immune responses to G. lamblia in children.

show abstract

Section: Discussionmentioning

confidence: 71%

Section: Introductionmentioning

confidence: 99%

Giardiasis Alters Intestinal Fatty Acid Binding Protein (I-FABP) and Plasma Cytokines Levels in Children in Brazil

et al. 2019

Self Cite

View full text Add to dashboard Cite

show abstract

“…4A). Accordingly, although several studies have described an important role of IL-17 in different models of giardiasis in recent years (41), this is the first report that describes this immune response in gerbil infections. In addition, a Th17 response to immunization with VSPs, consisting of an increase in IL-6, TGF-␤, and IL-17, shows the importance of these proteins as relevant protective immunogens of Giardia.…”

Section: Resultsmentioning

confidence: 84%

Cytokines, Antibodies, and Histopathological Profiles during Giardia Infection and Variant-Specific Surface Protein-Based Vaccination

et al. 2018

View full text Add to dashboard Cite

Giardiasis is one of the most common human intestinal diseases worldwide. Several experimental animal models have been used to evaluate infections, with gerbils () being the most valuable model due to their high susceptibility to infection, abundant shedding of cysts, and pathophysiological alterations and signs of disease similar to those observed in humans. Here, we report cytokine and antibody profiles both during the course of infection in gerbils and after immunization with a novel oral vaccine comprising a mixture of purified variant-specific surface proteins (VSPs). Transcript levels of representative cytokines of different immune profiles as well as macro- and microtissue alterations were assessed in Peyer's patches, mesenteric lymph nodes, and spleens. During infection, cytokine responses showed a biphasic profile: an early induction of Th1 (gamma interferon [IFN-γ], interleukin-1β [IL-1β], IL-6, and tumor necrosis factor [TNF]), Th17 (IL-17), and Th2 (IL-4) cytokines, together with intestinal alterations typical of inflammation, followed by a shift toward a predominant Th2 (IL-5) response, likely associated with a counterregulatory mechanism. Conversely, immunization with an oral vaccine comprising the entire repertoire of VSPs specifically showed high levels of IL-17, IL-6, IL-4, and IL-5, without obvious signs of inflammation. Both immunized and infected animals developed local (intestinal secretory IgA [S-IgA]) and systemic (serum IgG) humoral immune responses against VSPs; however, only infected animals showed evident signs of giardiasis. This is the first comprehensive report of cytokine expression and anti- antibody production during infection and VSP vaccination in gerbils, a reliable model of the human disease.

show abstract

“…Though both IFN-γ and IL-4 are increased in sera from humans infected with Giardia [67, 85], there is no substantial defect in parasite clearance when IFN-γ and IL-4-deficient female mice are infected [83]. It is becoming increasingly evident that IL-17, within the context of a Giardia infection, is essential for protective immunity [86]. This pro-inflammatory cytokine is produced by Th17 cells that require both IL-6 and TGF-β for their development.…”

Section: Protective Immunity Towards Giardiamentioning

confidence: 99%

The Intersection of Immune Responses, Microbiota, and Pathogenesis in Giardiasis

Fink

Singer

2017

Trends in Parasitology

Self Cite

104

View full text Add to dashboard Cite

Giardia lamblia is one of the most common infectious protozoans in the world. Giardia rarely causes severe life-threatening diarrhea, and may even have a slight protective effect in this regard, but it is a major contributor to malnutrition and growth faltering in children in the developing world. Giardia infection also appears to be a significant risk factor for post-infectious irritable bowel and chronic fatigue syndromes. In this review we highlight recent work focused on the impact of giardiasis and the mechanisms that contribute to the various outcomes of this infection, including changes in the composition of the microbiota, activation of immune responses, and immunopathology.

show abstract

Control of Giardiasis by Interleukin-17 in Humans and Mice—Are the Questions All Answered?

Cited by 22 publications

References 37 publications

Giardiasis Alters Intestinal Fatty Acid Binding Protein (I-FABP) and Plasma Cytokines Levels in Children in Brazil

Giardiasis Alters Intestinal Fatty Acid Binding Protein (I-FABP) and Plasma Cytokines Levels in Children in Brazil

Cytokines, Antibodies, and Histopathological Profiles during Giardia Infection and Variant-Specific Surface Protein-Based Vaccination

The Intersection of Immune Responses, Microbiota, and Pathogenesis in Giardiasis

Contact Info

Product

Resources

About