Trichuris suis ova in inflammatory bowel disease

Pre-clinical evaluation of the effect of co-medication with antibiotics and oral steroids in Göttingen Minipigs on the biological activity of the probiotic medicinal product TSO (Trichuris suis ova)

The probiotic medicinal product TSO (Trichuris suis ova) is administered to patients with active ulcerative colitis in an ongoing clinical phase IIb trial where the typical co-medications are steroids (prednisolone or budesonide) and antibiotics (e.g., phenoxymethylpenicillin). The present pre-clinical study evaluates the effects of these co-medications on the biological activity of TSO in Göttingen Minipigs. This translationally relevant pre-clinical model allows administration of TSO with and without oral steroids or antibiotics in a manner similar to the administration to patients, followed by quantification of the biological activity of TSO. The biological activity of TSO was not affected by oral steroids but was reduced by oral antibiotics. Fecal calprotectin, the common marker of intestinal inflammation in patients with UC, did not differ between groups.

Whip-LAMP: a novel LAMP assay for the detection of Trichuris muris-derived DNA in stool and urine samples in a murine experimental infection model

Background

Trichuris trichiura (human whipworm) infects an estimated 477 million individuals worldwide. In addition to T. trichiura, other Trichuris species can cause an uncommon zoonosis and a number of human cases have been reported. The diagnosis of trichuriasis has relied traditionally on microscopy. Recently, there is an effort to use molecular diagnostic methods, mainly qPCR. LAMP technology could be an alternative for qPCR especially in low-income endemic areas. Trichuris muris, the causative agent of trichuriasis in mice, is of great importance as a model for human trichuriasis. Here, we evaluate the diagnostic utility of a new LAMP assay in an active experimental mouse trichuriasis in parallel with parasitological method by using stool and, for the first time, urine samples.

Methods

Stool and urine samples were collected from mice infected with eggs of T. muris. The dynamics of infection was determined by counting the number of eggs per gram of faeces. A LAMP based on the 18S rRNA gene from T. muris was designed. Sensitivity and specificity of LAMP was tested and compared with PCR. Stool and urine samples were analysed by both LAMP and PCR techniques.

Results

Trichuris muris eggs were detected for the first time in faeces 35 days post-infection. LAMP resulted specific and no cross-reactions were found when using 18 DNA samples from different parasites. The detection limit of the LAMP assay was 2 pg of T. muris DNA. When testing stool samples by LAMP we obtained positive results on day 35 p.i. and urine samples showed amplification results on day 20 p.i., i.e. 15 days before the onset of T. muris eggs in faeces.

Conclusions

To the best of our knowledge, we report, for the first time, a novel LAMP assay (Whip-LAMP) for sensitive detection of T. muris DNA in both stool and urine samples in a well-established mice experimental infection model. Considering the advantages of urine in molecular diagnosis in comparison to stool samples, should make us consider the possibility of starting the use urine specimens in molecular diagnosis and for field-based studies of human trichuriasis where possible. Further studies with clinical samples are still needed.

Preventive Trichuris suis ova (TSO) treatment protects immunocompetent rabbits from DSS colitis but may be detrimental under conditions of immunosuppression

Trichuris suis ova (TSO) have been tested for therapeutic application in inflammatory bowel diseases (IBD) yet understanding of the underlying mechanisms and safety in an immunocompromised host is limited due to lack of a suitable animal model. We used a recently established rabbit model of dextran sodium sulphate (DSS) induced colitis to study the efficacy, mechanisms and safety of TSO therapy in immunocompetent and immunosuppressed animals. TSO treatment prevented the DSS induced weight loss, delayed the onset of DSS induced symptoms by 2 days and significantly reduced the disease activity (DAI). TSO treatment protected caecal histology and prevented the colitis-associated loss in faecal microbiota diversity. Mainly the transcriptome of lamina propria mononuclear cells (LPMC) was affected by TSO treatment, showing dampened innate and adaptive inflammatory responses. The protective effect of TSO was lost in immunosuppressed rabbits, where TSO exacerbated colitis. Our data show that preventive TSO treatment ameliorates colitis severity in immunocompetent rabbits, modulates LPMC immune responses and reduces faecal dysbiosis. In contrast, the same TSO treatment exacerbates colitis in immunosuppressed animals. Our data provide further evidence for a therapeutic effect of TSO in IBD, yet caution is required with regard to TSO treatment in immunosuppressed patients.

Immunomodulatory effects of excretory/secretory compounds from Contracaecum osculatum larvae in a zebrafish inflammation model

Excretory/secretory (ES) compounds isolated from third-stage larvae of the anisakid nematode Contracaecum osculatum parasitizing liver of Baltic cod were investigated for effects on immune gene expression in a zebrafish LPS-induced inflammation model. ES products containing a series of proteins, of which some had enzymatic activity, were injected solely or with LPS. ES proteins alone induced up-regulation of a number of immune-related genes, but generally to a lower degree compared to LPS. When co-injected with LPS, the worm products exacerbated merely expression of five genes affecting Th1, Th2, Th17 and innate responses compared to the LPS-injected group. However, the level of overexpression decreased in an inverse dose-dependent manner. The immune regulating action of C. osculatum ES products is interpreted as an important evolutionary ability of larval parasites in the transport host which makes it less susceptible to host immune responses whereby the probability of reaching the final host is increased.

Identifying the immunomodulatory components of helminths

Immunomodulatory components of helminths offer great promise as an entirely new class of biologics for the treatment of inflammatory diseases. Here, we discuss the emerging themes in helminth-driven immunomodulation in the context of therapeutic drug discovery. We broadly define the approaches that are currently applied by researchers to identify these helminth molecules, highlighting key areas of potential exploitation that have been mostly neglected thus far, notably small molecules. Finally, we propose that the investigation of immunomodulatory compounds will enable the translation of current and future research efforts into potential treatments for autoimmune and allergic diseases, while at the same time yielding new insights into the molecular interface of host-parasite biology.

Inflammatory bowel disease therapies discontinued between 2009 and 2014

INTRODUCTION

New therapeutic approaches are currently under development, which consider the fundamental mechanisms involved in the pathogenesis of inflammatory bowel disease (IBD). The disease is associated with inflamed intestinal and colonic mucosa in response to the dysregulated immune system.

AREAS COVERED

The aim of this article is to review drugs that have been designed for the treatment of IBD and discontinued between 2009 and 2014. Herein, nine molecules with different mechanisms of action are under review. Brodalumab, daclizumab, elubrixin and vatelizumab were withdrawn from the Phase II trial due to the lack of efficacy. Abatacept was not significantly superior to the placebo in the rate of remission and its Phase III trials were stopped. CNDO-210 and Catridecacog were discontinued due to safety concerns and lack of efficacy, respectively. Finally, NU-206 and alkaline phosphatase also ceased in development during Phase I and II tests.

EXPERT OPINION

The development in our knowledge and understanding of the pathophysiology of IBD and the identification of key objectives for the future play significant roles in IBD therapeutic development. Furthermore, well-planned clinical trials with concise measures of efficacy and safety are required to better decide whether to extend or terminate the development process. Some anti-inflammatory cytokines such as IL-2, IL-12, IL-17, IL-18, IL-23 and INF-γ could garner more attention in the future.

Oral administration of dextran sodium sulphate induces a caecum-localized colitis in rabbits

Trichuris suis ova (TSO) have shown promising results in the treatment of inflammatory bowel disease (IBD) but the mechanisms which underlies this therapeutic effect cannot be studied in mice and rats as T. suis fails to colonize the rodent intestine, whilst hatching in humans and rabbits. As a suitable rabbit IBD model is currently not available, we developed a rabbit colitis model by administration of dextran sodium sulphate (DSS). White Himalayan rabbits (n = 12) received 0.1% DSS in the daily water supply for five days. Clinical symptoms were monitored daily, and rabbits were sacrificed at different time points. A genomewide expression analysis was performed with RNA isolated from caecal lamina propria mononuclear cells (LPMC) and intestinal epithelial cells (IEC). The disease activity index of DSS rabbits increased up to 2.1 ± 0.4 (n = 6) at day 10 (controls <0.5). DSS induced a caecum-localized pathology with crypt architectural distortion, stunted villous surface and inflammatory infiltrate in the lamina propria. The histopathology score reached a peak of 14.2 ± 4.9 (n = 4) at day 10 (controls 7.7 ± 0.9, n = 5). Expression profiling revealed an enrichment of IBD-related genes in both LPMC and IEC. Innate inflammatory response, Th17 signalling and chemotaxis were among the pathways affected significantly. We describe a reproducible and reliable rabbit model of DSS colitis. Localization of the inflammation in the caecum and its similarities to IBD make this model particularly suitable to study TSO therapy in vivo.

Intestinal Microbiome, Small Intestinal Bacterial Overgrowth and Inflammatory Bowel Diseases - What are the Connections?

IBD (inflammatory bowel diseases) represent chronic idiopathic inflammatory diseases, prone to relapse in the digestive tract; it is estimated that they result from the interaction of the intestinal microbiome with the intestinal immune system. The inflammatory microbiome exerts multiple beneficial roles. Perhaps the central element to developing IBD is dysbiosis; there is still an incompletely established association between intestinal microbiome changes in patients with IBD and SIBO (small intestinal bacterial overgrowth). Influencing the intestinal microbiome may play an adjuvant therapeutic role in the treatment of IBD. We present a synthesis of the connections between the entities mentioned above.

Systematic review of complementary and alternative medicine treatments in inflammatory bowel diseases

OBJECTIVE

We performed a systematic review for Complementary and Alternative Medicine [CAM] as defined by the National Institute of Health in Inflammatory Bowel Disease [IBD], ie Crohn's disease [CD] and ulcerative colitis [UC], with the exception of dietary and nutritional supplements, and manipulative therapies.

METHODS

A computerized search of databases [Cochrane Library, Pubmed/Medline, PsychINFO, and Scopus] through March 2014 was performed. We screened the reference sections of original studies and systematic reviews in English language for CAM in IBD, CD and UC. Randomized controlled trials [RCT] and controlled trials [CT] were referred and assessed using the Cochrane risk of bias tool.

RESULTS

A total of: 26 RCT and 3 CT for herbal medicine, eg aloe-vera gel, andrographis paniculata, artemisia absinthium, barley foodstuff, boswellia serrata, cannabis, curcumin, evening primrose oil, Myrrhinil intest®, plantago ovata, silymarin, sophora, tormentil, wheatgrass-juice and wormwood; 1 RCT for trichuris suis ovata; 7 RCT for mind/body interventions such as lifestyle modification, hypnotherapy, relaxation training and mindfulness; and 2 RCT in acupuncture; were found. Risk of bias was quite heterogeneous. Best evidence was found for herbal therapy, ie plantago ovata and curcumin in UC maintenance therapy, wormwood in CD, mind/body therapy and self-intervention in UC, and acupuncture in UC and CD.

CONCLUSIONS

Complementary and alternative therapies might be effective for the treatment of inflammatory bowel diseases; however, given the low number of trials and the heterogeneous methodological quality of trials, further in-depth research is necessary.