Chronic Intestinal Infection Research Articles

The major secreted protein of the whipworm parasite tethers to matrix and inhibits interleukin-13 function

Infection by soil transmitted parasitic helminths, such as Trichuris spp, are ubiquitous in humans and animals but the mechanisms determining persistence of chronic infections are poorly understood. Here we show that p43, the single most abundant protein in T. muris excretions/secretions, is non-immunogenic during infection and has an unusual sequence and structure containing subdomain homology to thrombospondin type 1 and interleukin (IL)−13 receptor (R) α2. Binding of p43 to IL-13, the key effector cytokine responsible for T. muris expulsion, inhibits IL-13 function both in vitro and in vivo. Tethering of p43 to matrix proteoglycans presents a bound source of p43 to facilitate interaction with IL-13, which may underpin chronic intestinal infection. Our results suggest that exploiting the biology of p43 may open up new approaches to modulating IL-13 function and control of Trichuris infections.

TO FIND RELATIONSHIP BETWEEN COLONIC MUCOSAL CHANGES IN PATIENTS OF LIVER CIRRHOSIS WITH PORTAL HYPERTENSION.

Background: The aim of the study is to find relationship between Colonic Mucosal changes in patients of Liver Cirrhosis with Portal Hypertension conducted at MGM Medical College & M. Y. Hospital, Indore for one year.
 Result: The commonest symptom in patients was abdominal distension 30 (100%), next common was jaundice 20 (66.7%), malena 17 (56.7%), hemetemesis 10(33.3%), hematochezia 10(33.3%), and pruritis 2(6.6%) was noted.
 It is evident from table no .13 that out of 30 patients , serum prothrombin time was prolonged in 30 (100%) patients ,serum albumin was decreased in 20 (66.7%) patients , platelet count was decreased in 16 (53.3%) , serum bilirubin was raised in 14 (46.7%) patients , SGOT/SGPT was raised in 17 (56.7%) patients.
 Conclusion: Our study states that most of the changes which we found on colonoscopic studies were similar to other studies. The only finding which we got in excess in comparison to other studies was colitis like abnormality which was 73.3% which may be probably due to chronic intestinal infections which occur in our country.
 Keywords: Colonic Mucosal, Liver Cirrhosis, Portal, Hypertension.

Histopathological changes of chronic cestodes infection in local domesticated ducks (Anas platyrhynchas) in Baghdad city.

This study was conducted to investigate the histopathological changes of cestodes chronic intestinal infections in ten local domesticated ducks (Anas platyrhynchas) during the period 1/9/2016- 1/10/2017 in Baghdad city. Results showed severe destruction in the intestinal mucosa ,sloughing and desquamation of the epithelia and severe destruction with distortion or complete loss of the intestinal villi, complete loss of the mucosal and submucosa layers with destruction of intestinal glands and there is a severe infiltration of inflammatory cells mainly mononuclear cells in the lamina propria, and a focal necrosis in the intestinal mucosa.The submucosa showed an infiltration of macrophages and few lymphocytes, severe necrosis , calcification in some mucosal glands or with a cystic dilation with cellular debris in their lumen surrounded by inflammatory cells infiltration mainly mononuclear and plasma cells.The conclusion of the present study was that the cestodes chronic infection cause severe inflammatory response mainly lymphocytes and monocytes in mucosa and sub mucosa and destruction of some intestinal glands of the intestine.

Identification of the Apa protein secreted by Mycobacterium avium subsp. paratuberculosis as a novel fecal biomarker for Johne's disease in cattle.

Paratuberculosis (PTB) or Johne's disease is a chronic intestinal infection of ruminants, caused by Mycobacterium avium subsp. paratuberculosis. The shedding of mycobacteria in the feces starts at the initial stages and increases with disease progression, suggesting that antigens secreted by mycobacteria could be excreted in the feces. Previously, we demonstrated that the alanine and proline-rich antigen (Apa), a secretory antigen of Map, could be detected in the intestine of cows with PTB using a monoclonal antibody. In this study, we verified whether this protein can be found in consistently detectable levels in the feces of cattle with PTB. Feces were obtained from cows with Johne's disease confirmed by laboratory tests, cows with suspected PTB based on seropositivity and from PTB-free control cows. Samples were immunoprecipitated using anti-Apa monoclonal antibody and analyzed by immunoblot. The Apa was detected as a 60/70 kDa doublet band in all samples obtained from animals with laboratory-confirmed disease and in a substantial proportion of seropositive asymptomatic animals, but not in the control samples. Additionally, the antigen was detected in the feces of animals with Johne's disease by ELISA. This study strongly suggests that Apa is a potential fecal biomarker of Johne's disease that could serve for immunodiagnosis.

Atrophy of skin-draining lymph nodes predisposes for impaired immune responses to secondary infection in mice with chronic intestinal nematode infection.

Intestinal nematodes suppress immune responses in the context of allergy, gut inflammation, secondary infection and vaccination. Several mechanisms have been proposed for this suppression including alterations in Th2 cell differentiation and increased Treg cell suppressive function. In this study, we show that chronic nematode infection leads to reduced peripheral responses to vaccination because of a generalized reduction in the available responsive lymphocyte pool. We found that superficial skin-draining lymph nodes (LNs) in mice that are chronically infected with the intestinal nematode Heligmosomides polygyrus, do not reach the same cellularity as worm-free mice upon subsequent BCG infection in the skin. B cells and T cells, all declined in skin-draining LN of H. polygyrus-infected mice, resulting in LNs atrophy and altered lymphocyte composition. Importantly, anti-helminthic treatment improved lymphocyte numbers in skin-draining LN, indicating that time after de-worming is critical to regain full-scale LN cellularity. De-worming, and time for the skin LN to recover cellularity, also mended responses to Bacille Calmette-Guerin (BCG) in the LN draining the footpad injection site. Thus, our findings show that chronic nematode infection leads to a paucity of lymphocytes in peripheral lymph nodes, which acts to reduce the efficacy of immune responses at these sites.

Duodenal strongyloidiasis infection mimicking lymphangiectasia

Strongyloides stercoralis infection usually causes a chronic asymptomatic intestinal infection or otherwise non-specific generalized complaints. The diagnosis of strongyloidiasis by routine stool examination is very limited. Endoscopic findings in strongyloidiasis range from mucosal granularity to friable edema to frank ulceration or Small bowel obstruction secondary to intense infestation. The pathological examination of tissue biopsy and aspirate can give the definitive diagnosis. We report a case of middle age patient who presented with the symptoms of weight loss and diarrhea. On evaluation, upper GI endoscopy (EGD) showed the findings of lymphangiectasia but biopsy findings were consistent with strongyloidiasis which was successfully treated with Ivermectin 200 μg/kg, given for two days.Asian Journal of Medical Sciences Vol.8(5) 2017 98-100

CNS depressant and analgesic effects of Withania coagulans (Stocks) dunal fruits collected from Khuzdar district of Balochistan, Pakistan

Withania coagulans (Stocks) Dunal (Solanaceae) have been reported with various uses such as emetic, sedative, diuretic, alterative in chronic liver disorders, dyspepsia, intestinal infections and colic pain. This study aims to investigate the central nervous system (CNS) depressant, anxiolytic and analgesic effects of methanolic extract of W. coagulans. CNS depressant activity of crude methanolic extract of W. coagulans fruits was evaluated using standard animal behavioural models such as open field, cage crossing, rearing and traction test. Anxiolytic activity was evaluated through forced swimming test whereas analgesic activity was carried out via acetic acid induced writhing and formalin test in mice. The extract (100 and 250mg/kg) showed a dose-dependent suppression of motor and exploratory (Neuropharmacological) activity for mice in open field, cage crossing, rearing and traction test. Significant writhing effect i.e. decrease in number of writhes as well as analgesic effects were observed (P<0.05).The findings of current research work supports the CNS sedative and analgesic potential of W. coagulans. Keywords: Analgesic; Writhing test; Balochistan; Khuzdar; Withania coagulans http://dx.doi.org/10.19045/bspab.2017.60066

PCR Inhibition of a Quantitative PCR for Detection of Mycobacterium avium Subspecies Paratuberculosis DNA in Feces: Diagnostic Implications and Potential Solutions.

Molecular tests such as polymerase chain reaction (PCR) are increasingly being applied for the diagnosis of Johne’s disease, a chronic intestinal infection of ruminants caused by Mycobacterium avium subspecies paratuberculosis (MAP). Feces, as the primary test sample, presents challenges in terms of effective DNA isolation, with potential for PCR inhibition and ultimately for reduced analytical and diagnostic sensitivity. However, limited evidence is available regarding the magnitude and diagnostic implications of PCR inhibition for the detection of MAP in feces. This study aimed to investigate the presence and diagnostic implications of PCR inhibition in a quantitative PCR assay for MAP (High-throughput Johne’s test) to investigate the characteristics of samples prone to inhibition and to identify measures that can be taken to overcome this. In a study of fecal samples derived from a high prevalence, endemically infected cattle herd, 19.94% of fecal DNA extracts showed some evidence of inhibition. Relief of inhibition by a five-fold dilution of the DNA extract led to an average increase in quantification of DNA by 3.3-fold that consequently increased test sensitivity of the qPCR from 55 to 80% compared to fecal culture. DNA extracts with higher DNA and protein content had 19.33 and 10.94 times higher odds of showing inhibition, respectively. The results suggest that the current test protocol is sensitive for herd level diagnosis of Johne’s disease but that test sensitivity and individual level diagnosis could be enhanced by relief of PCR inhibition, achieved by five-fold dilution of the DNA extract. Furthermore, qualitative and quantitative parameters derived from absorbance measures of DNA extracts could be useful for prediction of inhibitory fecal samples.

Clostridium perfringens Sialidases: Potential Contributors to Intestinal Pathogenesis and Therapeutic Targets.

Clostridium perfringens is a major cause of histotoxic and intestinal infections of humans and other animals. This Gram-positive anaerobic bacterium can produce up to three sialidases named NanH, NanI, and NanJ. The role of sialidases in histotoxic infections, such as gas gangrene (clostridial myonecrosis), remains equivocal. However, recent in vitro studies suggest that NanI may contribute to intestinal virulence by upregulating production of some toxins associated with intestinal infection, increasing the binding and activity of some of those toxins, and enhancing adherence of C. perfringens to intestinal cells. Possible contributions of NanI to intestinal colonization are further supported by observations that the C. perfringens strains causing acute food poisoning in humans often lack the nanI gene, while other C. perfringens strains causing chronic intestinal infections in humans usually carry a nanI gene. Certain sialidase inhibitors have been shown to block NanI activity and reduce C. perfringens adherence to cultured enterocyte-like cells, opening the possibility that sialidase inhibitors could be useful therapeutics against C. perfringens intestinal infections. These initial in vitro observations should be tested for their in vivo significance using animal models of intestinal infections.

Migratory CD103+ dendritic cells suppress helminth-driven type 2 immunity through constitutive expression of IL-12.

CD8α(+) and CD103(+) dendritic cells (DCs) play a central role in the development of type 1 immune responses. However, their role in type 2 immunity remains unclear. We examined this issue using Batf3(-/-) mice, in which both of these DC subsets are missing. We found that Th2 cell responses, and related events such as eosinophilia, alternative macrophage activation, and immunoglobulin class switching to IgG1, were enhanced in Batf3(-/-) mice responding to helminth parasites. This had beneficial or detrimental consequences depending on the context. For example, Batf3 deficiency converted a normally chronic intestinal infection with Heligmosomoides polygyrus into an infection that was rapidly controlled. However, liver fibrosis, an IL-13-mediated pathological consequence of wound healing in chronic schistosomiasis, was exacerbated in Batf3(-/-) mice infected with Schistosoma mansoni. Mechanistically, steady-state production of IL-12 by migratory CD103(+) DCs, independent of signals from commensals or TLR-initiated events, was necessary and sufficient to exert the suppressive effects on Th2 response development. These findings identify a previously unrecognized role for migratory CD103(+) DCs in antagonizing type 2 immune responses.

Ethanol extracts of Sanguisorba officinalis L. suppress TNF-α/IFN-γ-induced pro-inflammatory chemokine production in HaCaT cells

BackgroundSanguisorba officinalis L. (SOL) is a perennial plant widely distributed in Asia, its roots are well-known as a traditional herbal medicine to treat burns, chronic intestinal infections, scalds, and inflammation in Korea. Also, the roots of SOL are used for treatment of many types of allergic skin diseases, including urticarial, eczema, and allergic dermatitis. PurposeIn this study we investigated the underlying mechanism of anti-inflammatory effect of an ethanol extract of SOL roots (ESOL). Study designThe ability of ESOL to inhibit inflammatory skin disorder was tested in human keratinocyte HaCaT cells. MethodsViability test using MTT assay were used to determine non-cytotoxic concentrations of ESOL on HaCaT cells. ESOL-mediated inhibition of the tumor necrosis factor (TNF)-α/interferon (IFN)-γ-induced production of pro-inflammatory chemokines—such as macrophage-derived chemokine (MDC), regulated on activation, normal T-cell expressed and secreted (RANTES), interleukin (IL)-8, and thymus and activation regulated chemokine (TARC)—at the mRNA level was determined by real-time reverse transcription-polymerase chain reaction (RT-PCR). The ability of ESOL to reduce the expression of pro-inflammatory marker proteins was evaluated by Western blot analysis and immunocytochemistry. ResultsESOL reduced the production of MDC, RANTES, IL-8, and TARC in HaCaT cells stimulated with TNF-α/IFN-γ at both protein and mRNA levels. ESOL also suppressed the phosphorylation of signal transducer and activator of transcription (STAT)-1, extracellular signal-regulated kinase (ERK), and inhibited both nuclear factor of kappa light polypeptide gene enhancer in B-cells inhibitor-alpha (IκB-α) degradation and the nuclear translocation of NF-κB/p65. ESOL exerts anti-inflammatory effects by suppressing the expression of TNF-α/IFN-γ-stimulated chemokines and pro-inflammatory molecules via a blockade NF-κB, STAT-1, and ERK activation. ConclusionOur results suggest the preventive potential of ESOL as a herbal medicine for the treatment of inflammatory skin diseases.

Risk factors for Mycobacterium avium subsp. paratuberculosis (MAP) and Mycobacterium bovis coinfection at individual animal level in southern Chile cattle populations.

Mycobacterium avium subsp. paratuberculosis (MAP) causes a chronic intestinal infection mainly in domestic and wild ruminants and is transmitted primarily by the fecal-oral route. Mycobacterium bovis (M. bovis) produces a chronic infection principally of the respiratory system. It affects most domestic mammals, wild species, and humans and is spread via the respiratory or oral route. It is important to note that M. bovis is considered a major zoonotic agent. The term coinfection refers to the coexistence of two or more infectious agents in the same host. The goal of the present study was to assess management factors that may favor coinfection with MAP and M. bovis in cattle at an individual level. A cross-sectional study was conducted including 366 cattle from 11 herds. Diagnostic information for both pathogens and individual characteristics of the animals and management practices applied on them was collected from each herd. The results indicated a set of variables being more frequent in the coinfected group of animals and mainly related with biosecurity measures. This study provided regionally based data that may be used to design future control plans for both cattle infections in southern Chile.

Within- and between-host mathematical modeling of Mycobacterium avium subspecies paratuberculosis (MAP) infections as a tool to study the dynamics of host-pathogen interactions in bovine paratuberculosis

Paratuberculosis is a chronic intestinal infection of ruminants caused by Mycobacterium avium ssp. paratuberculosis (MAP). Although a small proportion of animals are able to clear the infection, the majority of exposed animals will become chronically infected for life. Substantial economic losses to the dairy industry are a result of the clinical manifestation of the disease; however, production losses and increased morbidity in subclinically affected animals are also important factors. Only a small fraction (approximately 10%) of chronically infected animals will develop a fatal progressive form of the disease. The progressive form of clinical paratuberculosis is characterized by chronic intractable diarrhea in cattle and weight loss, production losses and severe emaciation leading to death since no treatment is available. A schematic representation of current views regarding the dynamics and pathogenesis of paratuberculosis is depicted in Fig. 1. This special issue of Veterinary Research is a compilation of work that explores and connects the dynamics of MAP-host interaction biology at multiple levels. The aim of this work is to highlight the potential of mathematical modelling techniques in exploring knowledge gaps and alternative explanations for observations made in data from experimental and field studies, which may ultimately lead to a better understanding of this complex infection.

Exposure to cows is not associated with diarrhoea or impaired child growth in rural Odisha, India: a cohort study.

Exposure to animal livestock has been linked to zoonotic transmission, especially of gastrointestinal pathogens. Exposure to animals may contribute to chronic asymptomatic intestinal infection, environmental enteropathy and child under-nutrition in low-income settings. We conducted a cohort study to explore the effect of exposure to cows on growth and endemic diarrhoea in children aged <5 years in a rural, low-income setting in the Indian state of Odisha. The study enrolled 1992 households with 2739 children. Height measurements were available for 824 children. Exposure to cows was measured as (1) the presence of a cowshed within or outside the compound, (2) the number of cows owned by a household, and (3) the number of cowsheds located within 50 m of a household. In a sub-study of 518 households, fly traps were used to count the number of synanthropic flies that may act as vectors for gastrointestinal pathogens. We found no evidence that environmental exposure to cows contributes to growth deficiency in children in rural India, neither directly by affecting growth, nor indirectly by increasing the risk of diarrhoea. We found no strong evidence that the presence of a cowshed increased the number synanthropic flies in households.

Chronic infections of the small intestine.

Chronic infections of the small intestine cause significant morbidity and mortality globally. This review focuses on the recent advances in the field of our understanding of selected intestinal infections. Primary and secondary immunodeficiency increase the susceptibility to many chronic intestinal infections. Endoscopy and intestinal biopsies are central to establishing a diagnosis of these conditions. Tuberculosis (TB) remains a major global health challenge. Emerging therapeutic agents to counteract multidrug-resistant strains have shown clinical efficacy, but concerns regarding mortality remain. PCR-based diagnostic TB tests have the potential to reduce diagnostic delays, but remain to be validated for intestinal infections. Adjunctive diagnostic imaging modalities can differentiate infections from Crohn's disease with increasing accuracy. Whipple's disease remains rare, but there have been substantial advances in our understanding of the causative organism Tropheryma whipplei. Extended treatment with broad-spectrum antibiotics is effective in most cases. The narrow therapeutic window and limited armamentarium for treating invasive filamentous fungal infections contribute to their significant morbidity and high rates of mortality. The speed and accuracy of diagnosing chronic intestinal infections have improved with recent imaging and laboratory methodologies. Significant research opportunities remain for clinicians and scientists to improve the diagnostic accuracy and clinical outcomes of chronic intestinal infections.

Loss of the TGFβ-Activating Integrin αvβ8 on Dendritic Cells Protects Mice from Chronic Intestinal Parasitic Infection via Control of Type 2 Immunity

Chronic intestinal parasite infection is a major global health problem, but mechanisms that promote chronicity are poorly understood. Here we describe a novel cellular and molecular pathway involved in the development of chronic intestinal parasite infection. We show that, early during development of chronic infection with the murine intestinal parasite Trichuris muris, TGFβ signalling in CD4+ T-cells is induced and that antibody-mediated inhibition of TGFβ function results in protection from infection. Mechanistically, we find that enhanced TGFβ signalling in CD4+ T-cells during infection involves expression of the TGFβ-activating integrin αvβ8 by dendritic cells (DCs), which we have previously shown is highly expressed by a subset of DCs in the intestine. Importantly, mice lacking integrin αvβ8 on DCs were completely resistant to chronic infection with T. muris, indicating an important functional role for integrin αvβ8-mediated TGFβ activation in promoting chronic infection. Protection from infection was dependent on CD4+ T-cells, but appeared independent of Foxp3+ Tregs. Instead, mice lacking integrin αvβ8 expression on DCs displayed an early increase in production of the protective type 2 cytokine IL-13 by CD4+ T-cells, and inhibition of this increase by crossing mice to IL-4 knockout mice restored parasite infection. Our results therefore provide novel insights into how type 2 immunity is controlled in the intestine, and may help contribute to development of new therapies aimed at promoting expulsion of gut helminths.

The TGFβ-activating integrin αvβ8 on dendritic cells regulates type 2 immunity in the intestine to promote chronic parasitic infection (P3318)

Abstract The cytokine TGFβ is crucial in regulating immunity in the intestine, but its role and regulation during responses to intestinal infection is not well understood. We therefore addressed how TGFβ functions and is controlled during chronic intestinal infection, using the model murine parasite Trichuris muris (the human homologue of which affects ~600 million people world-wide, causing severe health problems). We found that TGFβ signalling is induced early during infection, specifically in CD4+ T-cells. This enhanced signalling involves expression of the TGFβ-activating integrin αvβ8 by dendritic cells (DCs). Importantly, mice lacking integrin αvβ8 on DCs are completely resistant to chronic infection with T. muris, indicating an important functional role for integrin αvβ8-mediated TGFβ activation in promoting chronic infection. Protection from infection is dependent on CD4+ T-cells, but is independent of Foxp3+ Tregs as mice depleted of Foxp3+ Tregs during infection remained susceptible to infection. Instead, lack of integrin αvβ8 on DCs led to an early increase in expression of the Th2 cytokine IL-13 by CD4+ T-cells which is required for protection from infection. Our results therefore provide novel insights into how type 2 immunity is controlled in the intestine during gastrointestinal parasite infection, and may help contribute to the development of new therapies aimed at promoting expulsion of gut parasites.

Association of Untypeable Enteropathogenic Escherichia coli (EPEC) Strains with Persistent Diarrhea in Children from the Region of Lower Silesia in Poland

Enteropathogenic Escherichia coli strains (EPEC) carrying the eae gene encoding intimin are divided into typical strains producing bundle forming pili, encoded by the bfpA gene, and atypical strains lacking the gene. In the study typical and atypical EPEC that did not agglutinated with EPEC polyvalent antisera but carrying virulence factors characteristic to other pathogenic E. coli i.e. diffusely adhering and enteroaggregative E. coli were isolated from 24 (43.6%) of 55 children > 10 years old with persistent diarrhea. These results indicated that non-typeable typical and atypical EPEC can contribute to chronic intestinal infections in teenagers.

Apoptotic effect of hot water extract of Sanguisorba officinalis L. in human oral cancer cells

Sanguisorba officinalis L. has been used in traditional Asian medicine to treat diseases including diarrhea, chronic intestinal infections, duodenal ulcers and bleeding. This study examined the antiproliferative effects and apoptotic activity of hot water extract of S. officinalis L. (HESO) on HSC4 and HN22 human oral cancer cells. The effects of HESO were evaluated by the 3-(4,5-dimethylthiazol-20yl)-(3-carboxymethoxyphenyl)-2-(4-sulphophenyl)-2H-tetrazolium (MTS) assay, 4'-6-diamidino-2-phenylindole (DAPI) staining and western blot analysis. HESO was found to inhibit cell growth and induce apoptosis in HSC4 and HN22 oral cancer cells. HESO downregulated myeloid cell leukemia-1 (Mcl-1) in HSC4 cells and was associated with the activation of Bak, resulting in Bak oligomerization on the mitochondrial outer membrane. HESO did not alter Mcl-1 expression in HN22 cells, but it decreased Sp1 expression. The downregulation of Sp1 by HESO in HN22 cells resulted in a decrease in survivin, a downstream target protein of Sp1. These results suggested that HESO inhibited the growth of oral cancer through either Mcl-1 or Sp1, indicating that HESO may serve as a potential drug candidate against oral cancer.

Protective effects of lactoferrin chimera and bovine lactoferrin in a mouse model of enterohaemorrhagic Escherichia coli O157:H7 infection1This article is part of a Special Issue entitled Lactoferrin and has undergone the Journal's usual peer review process.

Mice orally infected with enterohaemorrhagic Escherichia coli (EHEC) O157:H7 were used to evaluate the activity of bovine lactoferrin (bLF) and the synthetic peptide LFchimera. Groups of BALB/c mice inoculated intragastrically with EHEC O157:H7 showed chronic intestinal infection with the pathogen that persisted over 6 days and resulted in a high mortality rate (90%). LFchimera and kanamycin significantly decreased (40%) this mortality rate (P = 0.028). On the other hand, although mice administered with bLF showed an important reduction in mortality (50%), this was not statistically significant (P = 0.070). In infected and untreated mice, severe tubular necrosis, glomerular lesions, and moderate intratubular hyaline casts were found in the kidney. However, in the bLF and LFchimera groups we found a reduction in the damage and a substantial decrease in the bacterial concentration excreted in feces 48 h after infection. Furthermore, sepsis caused by EHEC was reduced by the treatments, evidenced by the fact that bacteria were not detected in the kidney or liver 72 h after infection. The results suggest the bLF and LFchimera could have potential as therapeutics in EHEC infections.