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1.
Nat Immunol ; 22(2): 216-228, 2021 02.
Article in English | MEDLINE | ID: mdl-33462454

ABSTRACT

CD4+ effector lymphocytes (Teff) are traditionally classified by the cytokines they produce. To determine the states that Teff cells actually adopt in frontline tissues in vivo, we applied single-cell transcriptome and chromatin analyses to colonic Teff cells in germ-free or conventional mice or in mice after challenge with a range of phenotypically biasing microbes. Unexpected subsets were marked by the expression of the interferon (IFN) signature or myeloid-specific transcripts, but transcriptome or chromatin structure could not resolve discrete clusters fitting classic helper T cell (TH) subsets. At baseline or at different times of infection, transcripts encoding cytokines or proteins commonly used as TH markers were distributed in a polarized continuum, which was functionally validated. Clones derived from single progenitors gave rise to both IFN-γ- and interleukin (IL)-17-producing cells. Most of the transcriptional variance was tied to the infecting agent, independent of the cytokines produced, and chromatin variance primarily reflected activities of activator protein (AP)-1 and IFN-regulatory factor (IRF) transcription factor (TF) families, not the canonical subset master regulators T-bet, GATA3 or RORγ.


Subject(s)
Bacteria/pathogenicity , Bacterial Infections/microbiology , CD4-Positive T-Lymphocytes/microbiology , CD4-Positive T-Lymphocytes/parasitology , Colon/microbiology , Colon/parasitology , Gastrointestinal Microbiome , Heligmosomatoidea/pathogenicity , Intestinal Diseases, Parasitic/parasitology , Animals , Bacteria/immunology , Bacterial Infections/genetics , Bacterial Infections/immunology , Bacterial Infections/metabolism , CD4-Positive T-Lymphocytes/immunology , CD4-Positive T-Lymphocytes/metabolism , Chromatin/genetics , Chromatin/metabolism , Citrobacter rodentium/immunology , Citrobacter rodentium/pathogenicity , Colon/immunology , Colon/metabolism , Cytokines/genetics , Cytokines/metabolism , Disease Models, Animal , Gene Expression Profiling , Heligmosomatoidea/immunology , Host-Pathogen Interactions , Interferon Regulatory Factors/genetics , Interferon Regulatory Factors/metabolism , Intestinal Diseases, Parasitic/genetics , Intestinal Diseases, Parasitic/immunology , Intestinal Diseases, Parasitic/metabolism , Male , Mice, Inbred C57BL , Mice, Transgenic , Nematospiroides dubius/immunology , Nematospiroides dubius/pathogenicity , Nippostrongylus/immunology , Nippostrongylus/pathogenicity , Phenotype , Salmonella enterica/immunology , Salmonella enterica/pathogenicity , Single-Cell Analysis , Transcription Factor AP-1/genetics , Transcription Factor AP-1/metabolism , Transcriptome
2.
J Helminthol ; 98: e41, 2024 May 24.
Article in English | MEDLINE | ID: mdl-38785193

ABSTRACT

Background: Inflammatory bowel disease is an autoimmune disease that affects the gut. T. spiralis larvae (E/S Ags) loaded on calcium-benzene-1,3,5-tricarboxylate metal-organic frameworks (Ca-BTC MOFs) were tested to determine whether they might prevent or cure acetic acid-induced murine colitis. Methods: T. spiralis larvae E/S Ags/Ca-BTC MOFs were used in prophylactic and therapeutic groups to either precede or follow the development of murine colitis. On the seventh day after colitis, mice were slaughtered. The effect of our target antigens on the progress of the colitis was evaluated using a variety of measures, including survival rate, disease activity index, colon weight/bodyweight, colon weight/length) ratios, and ratings for macroscopic and microscopic colon damage. The levels of inflammatory cytokines (interferon-γ and interleukin-4), oxidative stress marker malondialdehyde, and glutathione peroxidase in serum samples were evaluated. Foxp3 T-reg expression was carried out in colonic and splenic tissues. Results: T. spiralis larvae E/S Ags/Ca-BTC MOFs were the most effective in alleviating severe inflammation in murine colitis. The survival rate, disease activity index score, colon weight/length and colon weight/bodyweight ratios, and gross and microscopic colon damage scores have all considerably improved. A large decrease in proinflammatory cytokine (interferon-γ) and oxidative stress marker (malondialdehyde) expression and a significant increase in interleukin-4 and glutathione peroxidase expression were obtained. The expression of Foxp3+ Treg cells was elevated in colonic and splenic tissues. Conclusion: T. spiralis larvae E/S Ags/Ca-BTC MOFs had the highest anti-inflammatory, antioxidant, and cytoprotective capabilities against murine colitis and might be used to develop new preventative and treatment strategies.


Subject(s)
Colitis , Cytokines , Larva , Metal-Organic Frameworks , Trichinella spiralis , Animals , Mice , Metal-Organic Frameworks/chemistry , Colitis/prevention & control , Colitis/chemically induced , Colitis/parasitology , Trichinella spiralis/immunology , Antigens, Helminth/immunology , Disease Models, Animal , Colon/parasitology , Colon/pathology , Mice, Inbred BALB C , Female , Male
3.
PLoS Pathog ; 17(7): e1009768, 2021 07.
Article in English | MEDLINE | ID: mdl-34329367

ABSTRACT

The intestinal nematode parasite Trichuris muris dwells in the caecum and proximal colon driving an acute resolving intestinal inflammation dominated by the presence of macrophages. Notably, these macrophages are characterised by their expression of RELMα during the resolution phase of the infection. The RELMα+ macrophage phenotype associates with the presence of alternatively activated macrophages and work in other model systems has demonstrated that the balance of classically and alternatively activated macrophages is critically important in enabling the resolution of inflammation. Moreover, in the context of type 2 immunity, RELMα+ alternatively activated macrophages are associated with the activation of macrophages via the IL4Rα. Despite a breadth of inflammatory pathologies associated with the large intestine, including those that accompany parasitic infection, it is not known how colonic macrophages are activated towards an alternatively activated phenotype. Here, we address this important knowledge gap by using Trichuris muris infection, in combination with transgenic mice (IL4Rαfl/fl.CX3CR1Cre) and IL4Rα-deficient/wild-type mixed bone marrow chimaeras. We make the unexpected finding that education of colonic macrophages towards a RELMα+, alternatively activated macrophage phenotype during T. muris infection does not require IL4Rα expression on macrophages. Further, this independence is maintained even when the mice are treated with an anti-IFNγ antibody during infection to create a strongly polarised Th2 environment. In contrast to RELMα, PD-L2 expression on macrophages post infection was dependent on IL4Rα signalling in the macrophages. These novel data sets are important, revealing a surprising cell-intrinsic IL4R alpha independence of the colonic RELMα+ alternatively activated macrophage during Trichuris muris infection.


Subject(s)
Colon/immunology , Colon/parasitology , Intestinal Diseases, Parasitic/immunology , Macrophages/immunology , Trichuriasis/immunology , Animals , Intercellular Signaling Peptides and Proteins/immunology , Interleukin-4 Receptor alpha Subunit/immunology , Male , Mice , Mice, Inbred C57BL , Mice, Transgenic , Trichuris/immunology
4.
FASEB J ; 33(4): 5676-5689, 2019 04.
Article in English | MEDLINE | ID: mdl-30668930

ABSTRACT

Macrophages play central roles in immunity as early effectors and modulating adaptive immune reponses; we implicated macrophages in the anticolitic effect of infection with the tapeworm Hymenolepis diminuta. Here, gene arrays revealed that H. diminuta antigen (HdAg) evoked a program in murine macrophages distinct from that elicited by IL-4. Further, HdAg suppressed LPS-evoked release of TNF-α and IL-1ß from macrophages via autocrine IL-10 signaling. In assessing the ability of macrophages treated in vitro with an extract of H. diminuta [M(HdAg)] to affect disease, intravenous, but not peritoneal, injection of M(HdAg) protected wild-type but not RAG1-/- mice from dinitrobenzene sulphonic acid (DNBS)-induced colitis. Administration of splenic CD4+ T cells from in vitro cocultures with M(HdAg), but not those cocultured with M(IL-4) cells, inhibited DNBS-induced colitis; fractionation of the T-cell population indicated that the CD4+CD25+ T cells from cocultures with M(HdAg) drove the suppression of DNBS-induced colitis. Use of IL-4-/- or IL-10-/- CD4+ T cells revealed that neither cytokine alone from the donor cells was essential for the anticolitic effect. These data illustrate that HdAg evokes a unique regulatory program in macrophages, identifies HdAg-evoked IL-10 suppression of macrophage activation, and reveals the ability of HdAg-treated macrophages to educate ( i.e., condition) and mobilize CD4+CD25+ T cells, which could be deployed to treat colonic inflammation.-Reyes, J. L., Lopes, F., Leung, G., Jayme, T. S., Matisz, C. E., Shute, A., Burkhard, R., Carneiro, M., Workentine, M. L., Wang, A., Petri, B., Beck, P. L., Geuking, M. B., McKay, D. M., Macrophages treated with antigen from the tapeworm Hymenolepis diminuta condition CD25+ T cells to suppress colitis.


Subject(s)
Antigens, Helminth/immunology , CD4-Positive T-Lymphocytes/immunology , Cestoda/immunology , Colitis/immunology , Hymenolepis diminuta/immunology , Interleukin-2 Receptor alpha Subunit/immunology , Macrophages/immunology , Animals , Colitis/parasitology , Colon/immunology , Colon/parasitology , Cytokines/immunology , Humans , Interleukin-10/immunology , Interleukin-4/immunology , Macrophage Activation/immunology , Macrophages/parasitology , Male , Mice , Mice, Inbred BALB C
5.
Exp Parasitol ; 218: 108012, 2020 Nov.
Article in English | MEDLINE | ID: mdl-33011239

ABSTRACT

Chagas disease, caused by the protozoan Trypanosoma cruzi, is endemic in almost all countries of Latin America. In Brazil, oral infection is becoming the most important mechanism of transmission of the disease in several regions of the country. The gastrointestinal tract is the gateway for the parasite through this route of infection, however, little is known about the involvement of these organs related to oral route. In this sense, the present study evaluated the impact of oral infection on the digestive tract in mice infected by Berenice-78 (Be-78) T. cruzi strain, in comparison with the intraperitoneal route of infection. In this work, the intraperitoneal route group showed a peak of parasitemia similar to the oral route group, however the mortality rate among the orally infected animals was higher when compared to intraperitoneal route. By analyzing the frequency of blood cell populations, differences were mainly observed in CD4+ T lymphocytes, and not in CD8+, presenting an earlier reduction in the number of CD4+ T cells, which persisted for a longer period, in the animals of the oral group when compared with the intraperitoneal group. Animals infected by oral route presented a higher tissue parasitism and inflammatory infiltrate in stomach, duodenum and colon on the 28th day after infection. Therefore, these data suggest that oral infection has a different profile of parasitological and immune responses compared to intraperitoneal route, being the oral route more virulent and with greater tissue parasitism in organs of the gastrointestinal tract evaluated during the acute phase.


Subject(s)
Chagas Disease/pathology , Gastrointestinal Tract/pathology , Gastrointestinal Tract/parasitology , Trypanosoma cruzi/pathogenicity , Administration, Oral , Analysis of Variance , Animals , Chagas Disease/mortality , Chagas Disease/parasitology , Colon/parasitology , Colon/pathology , Duodenum/parasitology , Duodenum/pathology , Immunophenotyping , Male , Mice , Monocytes/pathology , Parasitemia/mortality , Parasitemia/parasitology , Stomach/parasitology , Stomach/pathology , Survival Rate
6.
Exp Parasitol ; 210: 107834, 2020 Mar.
Article in English | MEDLINE | ID: mdl-31978394

ABSTRACT

Studies suggest that the dose of the standard benznidazole (BNZ) treatment regimen might be too high. We investigated the efficacy of BNZ 20 and 40 mg/kg/day compared with standard dose (100 mg/kg/day) to induce cure in mice infected with Trypanosoma cruzi Y strain in the acute and chronic phases of Chagas' disease. Our findings indicate that an experimental treatment with a BNZ low-dose (40 mg/kg/day) is similarly effective as the usual dose in the chronic mice model (100% of cure). In addition, the treatment in the chronic model of Chagas' disease presented better results than the acute model and colon appears to be a key tissue when it comes to evaluating treatment efficacy compared to blood and heart. Therefore, our data suggest the reconsideration of the current therapy, mainly in the chronic phase of the disease.


Subject(s)
Chagas Disease/drug therapy , Nitroimidazoles/administration & dosage , Trypanocidal Agents/administration & dosage , Acute Disease , Animals , Blood/parasitology , Chagas Disease/parasitology , Chronic Disease , Colon/parasitology , Cyclophosphamide/administration & dosage , Cyclophosphamide/pharmacology , Cyclophosphamide/therapeutic use , Female , Heart/parasitology , Immunosuppression Therapy , Mice , Neglected Diseases/drug therapy , Neglected Diseases/parasitology , Nitroimidazoles/therapeutic use , Real-Time Polymerase Chain Reaction , Trypanocidal Agents/therapeutic use , Trypanosoma cruzi/drug effects , Trypanosoma cruzi/genetics , Trypanosoma cruzi/physiology
7.
Drug Resist Updat ; 44: 1-14, 2019 05.
Article in English | MEDLINE | ID: mdl-31112766

ABSTRACT

Entamoeba histolytica is the etiological agent of amebiasis, which is an endemic parasitic disease in developing countries and is the cause of approximately 70,000 deaths annually. E. histolytica trophozoites usually reside in the colon as a non-pathogenic commensal in most infected individuals (90% of infected individuals are asymptomatic). For unknown reasons, these trophozoites can become virulent and invasive, cause amebic dysentery, and migrate to the liver where they cause hepatocellular damage. Amebiasis is usually treated either by amebicides which are classified as (a) luminal and are active against the luminal forms of the parasite, (b) tissue and are effective against those parasites that have invaded tissues, and (c) mixed and are effective against the luminal forms of the parasite and those forms which invaded the host's tissues. Of the amebicides, the luminal amebicide, metronidazole (MTZ), is the most widely used drug to treat amebiasis. Although well tolerated, concerns about its adverse effects and the possible emergence of MTZ-resistant strains of E. histolytica have led to the development of new therapeutic strategies against amebiasis. These strategies include improving the potency of existing amebicides, discovering new uses for approved drugs (repurposing of existing drugs), drug rediscovery, vaccination, drug targeting of essential E. histolytica components, and the use of probiotics and bioactive natural products. This review examines each of these strategies in the light of the current knowledge on the gut microbiota of patients with amebiasis.


Subject(s)
Amebiasis/drug therapy , Amebiasis/prevention & control , Amebicides/therapeutic use , Entamoeba histolytica/drug effects , Molecular Targeted Therapy/methods , Protozoan Vaccines/administration & dosage , Amebiasis/immunology , Amebiasis/parasitology , Animals , Biological Products/therapeutic use , Colon/drug effects , Colon/parasitology , Colon/pathology , Drug Repositioning/methods , Entamoeba histolytica/pathogenicity , Entamoeba histolytica/physiology , Gastrointestinal Microbiome/immunology , Host-Parasite Interactions/immunology , Humans , Liver/drug effects , Liver/parasitology , Liver/pathology , Metronidazole/therapeutic use , Microbial Interactions , Probiotics/therapeutic use , Protozoan Vaccines/biosynthesis , Severity of Illness Index
8.
J Helminthol ; 94: e114, 2020 Jan 13.
Article in English | MEDLINE | ID: mdl-31928550

ABSTRACT

The gastrointestinal helminth parasites of 170 common wallaroos or euros, Osphranter robustus (Gould), collected from all mainland states in which the species occurs as well as the Northern Territory, are presented, including previously published data. A total of 65 species of helminths were encountered, including four species of anoplocephalid cestodes found in the bile ducts and small intestine, and 61 species of strongylid nematodes, all but two of which occurring in the stomach, and with the remainder occurring in the terminal ileum, caecum and colon. Among the mainland subspecies of O. robustus, 52 species of helminths were encountered in O. r. robustus, compared with 30 species in O. r. woodwardi and 35 species in O. r. erubescens. Of the parasite species encountered, only 17 were specific to O. robustus, the remaining being shared with sympatric host species. Host-specific species or species occurring in O. robustus at a high prevalence can be classified as follows: widely distributed; restricted to northern Australia; restricted to the northern wallaroo, O. r. woodwardi; found only in the euro, O. r. erubescens; found essentially along the eastern coast of Australia, primarily in O. r. robustus; and species with highly limited regional distributions. The data currently available suggest that the acquisition of a significant number of parasites is due to co-grazing with other macropodids, while subspeciation in wallaroos as well as climatic variables may have influenced the diversification of the parasite fauna.


Subject(s)
Helminthiasis , Helminths/isolation & purification , Intestines/parasitology , Macropodidae/parasitology , Strongylida Infections/veterinary , Animal Distribution , Animals , Australia/epidemiology , Bile Ducts/parasitology , Biodiversity , Cestoda/isolation & purification , Cestoda/parasitology , Colon/parasitology , Helminthiasis/parasitology , Helminthiasis/transmission , Helminths/parasitology , Host Specificity , Ileum/parasitology , Intestinal Diseases, Parasitic/veterinary , Nematoda/isolation & purification , Nematoda/parasitology , Stomach/parasitology , Strongylida/isolation & purification , Strongylida/parasitology , Strongylida Infections/parasitology , Strongylida Infections/transmission
9.
Parasitology ; 146(9): 1140-1149, 2019 08.
Article in English | MEDLINE | ID: mdl-29212561

ABSTRACT

The protozoan parasite Entamoeba histolytica is the microbial agent of amoebiasis - an infection that is endemic worldwide and is associated with high morbidity and mortality rates. As the disease develops, virulent E. histolytica deplete the mucus layer, interact with the intestinal epithelium, and then degrade the colonic mucosa and disrupt the extracellular matrix (ECM). Our research demonstrated that virulent parasites with an invasive phenotype display rapid, highly specific changes in their transcriptome (notably for essential factors involved in carbohydrate metabolism and the processing of glycosylated residues). Moreover, combined activation of parasite and host lytic enzymes leads to the destruction of the intestinal parenchyma. Together, these enzymes degrade the mucus layer and the ECM, and trigger the inflammatory response essential to the development of amoebiasis.


Subject(s)
Amebiasis/parasitology , Entamoeba histolytica/pathogenicity , Host-Parasite Interactions , Intestinal Mucosa/physiology , Intestinal Mucosa/parasitology , Signal Transduction , Amebiasis/physiopathology , Animals , Colon/cytology , Colon/parasitology , Genome, Bacterial , Humans , Inflammation , Transcriptome
10.
Dig Dis Sci ; 64(3): 729-739, 2019 03.
Article in English | MEDLINE | ID: mdl-30446929

ABSTRACT

BACKGROUND: The role of protease activated receptor-2 (PAR-2) in the pathogenesis of abdominal pain in irritable bowel syndrome (IBS) is not well defined. AIMS: To investigate the role of PAR-2-mediated visceral hypersensitivity in a post-infectious IBS (PI-IBS) mouse model. METHODS: T. spiralis-infected PI-IBS mouse model was used. Fecal serine protease activity and intestinal mast cells were evaluated. Intestinal permeability was assessed by urine lactulose/mannitol ratio, and colonic expressions of PAR-2 and tight junction (TJ) proteins were examined by Western blot. Intestinal immune profile was assessed by measuring Th (T helper) 1/Th2 cytokine expression. Visceral sensitivity was evaluated by abdominal withdrawal reflex in response to colorectal distention. RESULTS: Colonic PAR-2 expression as well as fecal serine protease activity and intestinal mast cell counts were elevated in PI-IBS compared to the control mice. Decreased colonic TJ proteins expression, increased lactulose/mannitol ratio, elevated colonic Th1/Th2 cytokine ratio, and visceral hypersensitivity were observed in PI-IBS compared to the control mice. Administration of PAR-2 agonist in control mice demonstrated similar changes observed in PI-IBS mice, while PAR-2 antagonist normalized the increased intestinal permeability and reduced visceral hypersensitivity observed in PI-IBS mice. CONCLUSIONS: PAR-2 activation increases intestinal permeability leading to immune activation and visceral hypersensitivity in PI-IBS mouse model.


Subject(s)
Abdominal Pain/chemically induced , Colon/drug effects , Hyperalgesia/chemically induced , Irritable Bowel Syndrome/metabolism , Oligopeptides/toxicity , Receptor, PAR-2/agonists , Abdominal Pain/immunology , Abdominal Pain/metabolism , Abdominal Pain/parasitology , Animals , Colon/immunology , Colon/metabolism , Colon/parasitology , Feces/enzymology , Hyperalgesia/immunology , Hyperalgesia/metabolism , Hyperalgesia/physiopathology , Irritable Bowel Syndrome/immunology , Irritable Bowel Syndrome/parasitology , Male , Mast Cells/drug effects , Mast Cells/immunology , Mast Cells/metabolism , Mice , Permeability/drug effects , Receptor, PAR-2/metabolism , Serine Proteases/metabolism , Signal Transduction , Th1 Cells/drug effects , Th1 Cells/immunology , Th1 Cells/metabolism , Th1-Th2 Balance/drug effects , Tight Junctions/drug effects , Tight Junctions/immunology , Tight Junctions/metabolism , Trichinella spiralis/pathogenicity , Trichinellosis/complications , Trichinellosis/parasitology
11.
Exp Parasitol ; 201: 34-41, 2019 Jun.
Article in English | MEDLINE | ID: mdl-31034815

ABSTRACT

Ovine Eimeria spp. infections cause increased mortality, reduced welfare and substantial economic losses, and anticocccidials are important for their control. Recent reports of anticoccidial resistance against ovine Eimeria spp. necessitate the development of in vitro methods for the detection of reduced anticoccidial efficacy, especially since the in vivo methods are both expensive, time consuming and requires the use of otherwise healthy animals. The aim of the present study was therefore to approach a preliminary standardization of in vitro assays for evaluation of the efficacy of the most commonly used anticoccidials in ruminants. For this purpose, apart from the evaluation of inhibition of oocyst sporulation, most effort was concentrated on assessment of the capacity of the different anticoccidials to inhibit both the invasion and further development (up to the first schizogony) of E. ninakohlyakimovae sporozoites in bovine colonic epithelial cells (BCEC). For this purpose, infected cultures were monitored 1, 8 and 15 days post infection to determine the infection rate, number of immature schizonts and number, size and appearance of mature schizonts, respectively. No clear inhibitory effect was found with any of the anticoccidial formulations tested, and we could not identify why there were no measurable effects from the different anticoccidials. Despite the lack of positive results, further investigations should be encouraged, as this could decrease the need for animal experiments and could be used in the initial assessment of anticoccidial efficacy of new drugs.


Subject(s)
Coccidiosis/veterinary , Coccidiostats/pharmacology , Eimeria/drug effects , Goat Diseases/parasitology , Animals , Cattle , Cells, Cultured , Coccidiosis/drug therapy , Coccidiosis/parasitology , Colon/cytology , Colon/parasitology , Decoquinate/pharmacology , Drug Resistance , Eimeria/growth & development , Eimeria/isolation & purification , Epithelial Cells/parasitology , Feces/parasitology , Goat Diseases/drug therapy , Goats , Intestinal Mucosa/cytology , Intestinal Mucosa/parasitology , Nitriles/pharmacology , Oocysts/isolation & purification , Schizonts/drug effects , Schizonts/growth & development , Sporozoites/isolation & purification , Sulfonamides/pharmacology , Triazines/pharmacology
12.
Immunology ; 154(1): 76-88, 2018 05.
Article in English | MEDLINE | ID: mdl-29121394

ABSTRACT

The tumour-like growth of larval Echinococcus multilocularis tissue (causing alveolar echinococcosis, AE) is directly linked to the nature/orientation of the periparasitic host immune-mediated processes. Parasite-mediated immune suppression is a hallmark triggering infection outcome in both chronic human and murine AE. So far, little is known about secondary systemic immune effects of this pathogen on other concomitant diseases, e.g. endogenous gut inflammation. We examined the influence of E. multilocularis infection on murine dextran sodium sulphate (DSS) -induced colitis. At 3 months after E. multilocularis infection (chronic stage), the mice were challenged with 3% DSS in the drinking water for 5 days plus subsequently with tap water (alone) for another 4 days. After necropsy, fixed tissues/organs were sectioned and stained with haematoxylin & eosin for assessing inflammatory reactions. Cytokine levels were measured by flow cytometry and quantitative RT-PCR. Colitis severity was assessed (by board-certified veterinary pathologists) regarding (i) colon length, (ii) weight loss and (iii) a semi-quantitative score of morphological changes. The histopathological analysis of the colon showed a significant reduction of DSS-induced gut inflammation by concomitant E. multilocularis infection, which correlated with down-regulation of T helper type 1 (Th1)/Th17 T-cell responses in the colon tissue. Echinococcus multilocularis infection markedly reduced the severity of DSS-induced gut inflammation upon down-regulation of Th1/Th17 cytokine expression and attenuation of CD11b+ cell activation. In conclusion, E. multilocularis infection remarkably reduces DSS-induced colitis in mice by attenuating Th1/Th17-mediated immune reactions.


Subject(s)
Colitis/prevention & control , Colon/immunology , Colon/parasitology , Dextran Sulfate , Echinococcosis/immunology , Echinococcosis/parasitology , Echinococcus multilocularis/immunology , Th1 Cells/immunology , Th1 Cells/parasitology , Th17 Cells/immunology , Th17 Cells/parasitology , Animals , CD11b Antigen/immunology , CD11b Antigen/metabolism , CD11c Antigen/immunology , CD11c Antigen/metabolism , Cells, Cultured , Colitis/chemically induced , Colitis/immunology , Colitis/metabolism , Colon/metabolism , Colon/pathology , Cytokines/immunology , Cytokines/metabolism , Disease Models, Animal , Echinococcosis/metabolism , Female , Host-Pathogen Interactions , Larva/immunology , Mice, Inbred C57BL , Spleen/immunology , Spleen/metabolism , Spleen/parasitology , Th1 Cells/metabolism , Th17 Cells/metabolism , Time Factors
13.
Emerg Infect Dis ; 24(8): 1541-1543, 2018 08.
Article in English | MEDLINE | ID: mdl-30015612

ABSTRACT

We detected a disease syndrome in free-ranging Australian cane toads involving atypical behavior and emaciation that is associated with a previously undescribed Entamoeba sp. that infiltrates the colonic lining, causing it to slough. The organism may become seasonally pathogenic when toads are under hydric and nutritional stress.


Subject(s)
Bufo marinus/parasitology , DNA, Protozoan/genetics , Disease Outbreaks , Entamoeba/genetics , Entamoebiasis/epidemiology , Entamoebiasis/veterinary , Animals , Colon/parasitology , Colon/pathology , Droughts , Emaciation/parasitology , Emaciation/pathology , Entamoeba/classification , Entamoeba/isolation & purification , Entamoeba/pathogenicity , Entamoebiasis/parasitology , Entamoebiasis/transmission , Introduced Species , Northern Territory/epidemiology , Phylogeny , Seasons , Tropical Climate
14.
Cytokine ; 111: 72-83, 2018 11.
Article in English | MEDLINE | ID: mdl-30118915

ABSTRACT

Helminth infection can reduce the severity of inflammatory bowel disease. However, the modulatory mechanisms elicited by helminth infection are not yet fully understood and vary depending on the experimental model. Herein we evaluated the effect of acute infection of BALB/c mice with Strongyloides venezuelensis on the clinical course of ulcerative colitis induced by Dextran Sulfate Sodium (DSS) treatment of these animals. For the experiments, S. venezuelensis-infected BALB/c mice were treated orally with 4% DSS solution for seven days. As controls, we used untreated S. venezuelensis infected, DSS-treated uninfected, and untreated/uninfected BALB/c mice. During DSS treatment, mice from the different groups were compared with regards to the clinical signs related to the severity of colitis and intestinal inflammation. Mice acutely infected with S. venezulensis and treated with DSS had reduced clinical score, shortening of the colon, and tissue inflammation. Moreover, DSS-treated and infected mice showed reduced IL-4, INF-γ, and IL-17 levels and increase of IL-10 production in the colon and/or in the supernatant of mesenteric lymph nodes cell cultures that resulted in lower eosinophil peroxidase and myeloperoxidase activity in colon homogenates, when compared with DSS-treated uninfected mice. DSS-treated infected mice also preserved the intestine architecture and had normal differentiation of goblet cells and mucus production in the colon mucosa. In conclusion, the data indicate that the clinical improvement reported in DSS-treated infected mice was accompanied by the lower production of Th1/Th2/Th17 pro-inflammatory cytokines, stimulation of IL-10, and induction of mucosal repair mechanisms.


Subject(s)
Colitis/immunology , Colon/immunology , Dextran Sulfate/toxicity , Interleukin-10/immunology , Strongyloides/immunology , Strongyloidiasis/immunology , Th1 Cells/immunology , Th17 Cells/immunology , Th2 Cells/immunology , Acute Disease , Animals , Colitis/chemically induced , Colitis/parasitology , Colitis/pathology , Colon/parasitology , Colon/pathology , Female , Goblet Cells/immunology , Goblet Cells/pathology , Mice , Mice, Inbred BALB C , Strongyloidiasis/chemically induced , Strongyloidiasis/pathology , Th1 Cells/pathology , Th17 Cells/pathology , Th2 Cells/pathology
15.
Scand J Gastroenterol ; 53(9): 1085-1088, 2018 Sep.
Article in English | MEDLINE | ID: mdl-30256685

ABSTRACT

Entamoeba histolytica colitis can mimic Crohn's disease. However, a fulminant infection can be life-threatening, especially after exposure to systemic steroids. We present a case of the patient who was initially diagnosed with ileocolonic Crohn's disease, but developed a hepatic E histolytica abscess while undergoing anti-TNF therapy. After revision of the initial diagnostic biopsies, the diagnosis was questioned and E histolytica was confirmed using PCR and histopathology. As intestinal amoebiasis is the most common form of amoebic infection, care should be taken in case of refractory IBD or at initial diagnosis in patients who travelled to endemic areas. We therefore discuss the epidemiology, clinical features, diagnostic tools and pathophysiology of E Histolytica in order to raise awareness among gastroenterologists treating patients with inflammatory bowel disease.


Subject(s)
Colon/pathology , Dysentery, Amebic/diagnosis , Entamoeba histolytica/isolation & purification , Liver Abscess, Amebic/diagnostic imaging , Colon/parasitology , Crohn Disease , Diagnosis, Differential , Female , Humans , Middle Aged , Tomography, X-Ray Computed
16.
Dig Dis Sci ; 63(6): 1473-1484, 2018 06.
Article in English | MEDLINE | ID: mdl-29569002

ABSTRACT

BACKGROUND: Trypanosoma cruzi (T. cruzi) infects millions of Latin Americans each year and can induce chagasic megacolon. Little is known about how serotonin (5-HT) modulates this condition. Aim We investigated whether 5-HT synthesis alters T. cruzi infection in the colon. MATERIALS AND METHODS: Forty-eight paraffin-embedded samples from normal colon and chagasic megacolon were histopathologically analyzed (173/2009). Tryptophan hydroxylase 1 (Tph1) knockout (KO) mice and c-KitW-sh mice underwent T. cruzi infection together with their wild-type counterparts. Also, mice underwent different drug treatments (16.1.1064.60.3). RESULTS: In both humans and experimental mouse models, the serotonergic system was activated by T. cruzi infection (p < 0.05). While treating Tph1KO mice with 5-HT did not significantly increase parasitemia in the colon (p > 0.05), rescuing its synthesis promoted trypanosomiasis (p < 0.01). T. cruzi-related 5-HT release (p < 0.05) seemed not only to increase inflammatory signaling, but also to enlarge the pericryptal macrophage and mast cell populations (p < 0.01). Knocking out mast cells reduced trypanosomiasis (p < 0.01), although it did not further alter the neuroendocrine cell number and Tph1 expression (p > 0.05). Further experimentation revealed that pharmacologically inhibiting mast cell activity reduced colonic infection (p < 0.01). A similar finding was achieved when 5-HT synthesis was blocked in c-KitW-sh mice (p > 0.05). However, inhibiting mast cell activity in Tph1KO mice increased colonic trypanosomiasis (p < 0.01). CONCLUSION: We show that mast cells may modulate the T. cruzi-related increase of 5-HT synthesis in the intestinal colon.


Subject(s)
Chagas Disease/metabolism , Colon/metabolism , Intestinal Diseases, Parasitic/metabolism , Mast Cells/metabolism , Megacolon/metabolism , Serotonin/biosynthesis , Trypanosoma cruzi/pathogenicity , Adult , Aged , Animals , Case-Control Studies , Chagas Disease/genetics , Chagas Disease/parasitology , Colon/parasitology , Host-Pathogen Interactions , Humans , Intestinal Diseases, Parasitic/genetics , Intestinal Diseases, Parasitic/parasitology , Male , Mast Cells/parasitology , Megacolon/genetics , Megacolon/parasitology , Mice, Inbred C57BL , Mice, Knockout , Middle Aged , Proto-Oncogene Proteins c-kit/genetics , Proto-Oncogene Proteins c-kit/metabolism , Time Factors , Tryptophan Hydroxylase/genetics , Tryptophan Hydroxylase/metabolism
17.
Parasitol Res ; 117(4): 1147-1158, 2018 Apr.
Article in English | MEDLINE | ID: mdl-29470711

ABSTRACT

Chagas disease is an infection caused by the parasite Trypanosoma cruzi that affects millions of people worldwide and is endemic in Latin America. Megacolon is the most frequent complication of the digestive chronic form and happens due to lesions of the enteric nervous system. The neuronal lesions seem to initiate in the acute phase and persist during the chronic phase, albeit the mechanisms involved in this process are still debated. Among the cells of the immune system possibly involved in this pathological process is the mast cell (MC) due to its well-known role in the bi-directional communication between the immune and nervous systems. Using ultrastructural analysis, we found an increased number of degranulated MCs in close proximity to nerve fibers in infected patients when compared with uninfected controls. We also immunostained MCs for the two pro-inflammatory molecules tryptase and chymase, the first being also important in neuronal death. The number of MCs immunostained for tryptase or chymase was increased in patients with megacolon, whereas increased tryptase staining was additionally observed in patients without megacolon. Moreover, we detected the expression of the tryptase receptor PAR2 in neurons of the enteric nervous system, which correlated to the tryptase staining results. Altogether, the data presented herein point to the participation of MCs on the denervation process that occurs in the development of T. cruzi-induced megacolon.


Subject(s)
Chagas Disease/immunology , Colon/pathology , Enteric Nervous System/immunology , Mast Cells/immunology , Megacolon/pathology , Neuroimmunomodulation/physiology , Trypanosoma cruzi/immunology , Aged , Animals , Chagas Disease/parasitology , Chymases/immunology , Coleoptera , Colon/parasitology , Enteric Nervous System/parasitology , Female , Humans , Male , Megacolon/parasitology , Middle Aged , Neurons/metabolism , Receptor, PAR-2 , Receptors, G-Protein-Coupled/metabolism , Tryptases/immunology
18.
Int J Mol Sci ; 19(10)2018 Oct 17.
Article in English | MEDLINE | ID: mdl-30336596

ABSTRACT

Senna and its main components sennosides are well-known effective laxative drugs and are used in the treatment of intestinal constipation in the world. Their potential side effects have attracted more attention in clinics but have little scientific justification. In this study, senna extract (SE), sennosides (SS), and sennoside A (SA) were prepared and used to generate diarrhea rats. The diarrhea rats were investigated with behaviors, clinical signs, organ index, pathological examination, and gene expression on multiple aquaporins (Aqps) including Aqp1, Aqp2, Aqp3, Aqp4, Aqp5, Aqp6, Aqp7, Aqp8, Aqp9, and Aqp11. Using qRT-PCR, the Aqp expression profiles were constructed for six organs including colon, kidney, liver, spleen, lung, and stomach. The Aqp alteration profiles were characterized and was performed with Principle Component Analysis (PCA). The SE treatments on the rats resulted in a significant body weight loss (p < 0.001), significant increases (p < 0.001) on the kidney index (27.72%) and liver index (42.55%), and distinguished changes with up-regulation on Aqps expressions in the kidneys and livers. The SS treatments showed prominent laxative actions and down regulation on Aqps expression in the colons. The study results indicated that the SE had more influence/toxicity on the kidneys and livers. The SS showed more powerful actions on the colons. We suggest that the caution should be particularly exercised in the patients with kidney and liver diseases when chronic using senna-based products.


Subject(s)
Aquaporins/genetics , Diarrhea/chemically induced , Gene Expression Profiling , Senna Extract/adverse effects , Animals , Aquaporins/metabolism , Colon/parasitology , Diarrhea/genetics , Diarrhea/pathology , Gene Expression Regulation , Hypoxanthine Phosphoribosyltransferase/genetics , Hypoxanthine Phosphoribosyltransferase/metabolism , Organ Specificity , Principal Component Analysis , RNA, Messenger/genetics , RNA, Messenger/metabolism , Rats , Sennosides , Weight Loss/drug effects
19.
J Helminthol ; 92(6): 752-759, 2018 Nov.
Article in English | MEDLINE | ID: mdl-29151395

ABSTRACT

A new genus and species of nematode, Tziminema unachi n. gen., n. sp. is described from the caecum and colon of Baird's tapir Tapirus bairdii (Gill, 1865), found dead in the Reserva de la Biósfera El Triunfo, Chiapas State, in the Neotropical realm of Mexico. Tziminema n. gen. differs from the other nine genera included in the Strongylinae by two main characteristics: having 7-9 posteriorly directed tooth-like structures at the anterior end of the buccal capsule, and the external surface of the buccal capsule being heavily striated. Phylogenetic analyses of the DNA sequences of the mitochondrial cytochrome c oxidase and nuclear DNA, including a partial sequence of the internal transcribed spacer 1, 5.8S and a partial sequence of the internal transcribed spacer 2 of the new taxon, confirmed its inclusion in Strongylinae and its rank as a new genus.


Subject(s)
Perissodactyla/parasitology , Strongyloidea/classification , Strongyloidea/isolation & purification , Animals , Cecum/parasitology , Cluster Analysis , Colon/parasitology , DNA, Helminth/chemistry , DNA, Helminth/genetics , DNA, Ribosomal/chemistry , DNA, Ribosomal/genetics , DNA, Ribosomal Spacer/chemistry , DNA, Ribosomal Spacer/genetics , Electron Transport Complex IV/genetics , Mexico , Microscopy , Microscopy, Electron, Scanning , Phylogeny , RNA, Ribosomal, 5.8S/genetics , Sequence Analysis, DNA , Strongyloidea/anatomy & histology , Strongyloidea/genetics
20.
Microb Pathog ; 112: 1-4, 2017 Nov.
Article in English | MEDLINE | ID: mdl-28923601

ABSTRACT

Studies show that highly diluted medications demonstrate benefits in treating infections, constituting an alternative for their treatment. The present study evaluated the effects of Lycopodium clavatum, dynamization 13c, in Wistar rats infected with T. cruzi. In this study 42 male rats were intraperitoneally inoculated with T. cruzi - Y strain and allocated into groups: IC (infected control group) and Ly (treated with L. clavatum 13c). The cytokines dosage (IFN-γ, IL-12, IL-10, IL-4), quantification and morphometry of myenteric neurons were evaluated. The treatment with L. clavatum modifies the immune response, with increase of IFN-γ on day 10 a.i. and IL-12 on day 24 a.i., decrease of IL-10 concentration on day 10 a.i. and subsequent increase of this cytokine and IL-4 on day 24 a.i., affording a bigger number of myenteric neurons compared to IC group. Thus, L. clavatum 13c promoted on rats infected with T. cruzi a beneficial immunomodulatory action reducing the pathogenic progression of digestive Chagas disease.


Subject(s)
Chagas Disease/immunology , Immunomodulation , Lycopodium/chemistry , Neurons/immunology , Plant Extracts/pharmacology , Trypanosoma cruzi/drug effects , Animals , Cell Body/drug effects , Cell Body/immunology , Cell Body/parasitology , Cell Body/pathology , Chagas Disease/drug therapy , Colon/innervation , Colon/parasitology , Colon/pathology , Cytokines/metabolism , Digestion , Disease Models, Animal , Homeopathy , Interferon-gamma/metabolism , Interleukin-10/metabolism , Interleukin-12/metabolism , Interleukin-4/metabolism , Male , Neurons/drug effects , Neurons/parasitology , Neurons/pathology , Rats , Rats, Wistar , Trypanosoma cruzi/immunology , Trypanosoma cruzi/pathogenicity
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