Adeno-associated virus mediated delivery of Tregitope 167 ameliorates experimental colitis

Aim: To explore the anti-inflammatory potential of adeno-associated virus-mediated delivery of Tregitope 167 in an experimental colitis model. Methods: The trinitrobenzene sulfonate (TNBS) model of induced colitis was used in Balb/c mice. Subsequently after intravenous adeno-associated virus-mediated regulatory T-cell epitopes (Tregitope) delivery, acute colitis was initiated by intra-rectal administration of 1.5 mg TNBS in 40% ethanol followed by a second treatment with TNBS (0.75 mg in 20% ethanol) 8 d later. Control groups included mice not treated with TNBS (healthy control group) and mice treated by TNBS only (diseased group). At the time of sacrifice colon weight, the disease activity index and histology damage score were determined. Immunohistochemical staining of the colonic tissues was performed to asses the cellular infiltrate and the presence of transcription factor forkhead Box-P3 (Foxp3). Thymus, mesenteric lymph nodes, liver and spleen tissue were collected and the corresponding lymphocyte populations were further assessed by flow cytometry analysis for the expression of CD4+ T cell and regulatory T cell associated markers. Results: The Tregitope 167 treated mice gained an average of 4% over their initial body weight at the time of sacrifice. In contrast, the mice treated with TNBS alone (no Tregitope) developed colitis, and lost 4% of their initial body weight at the time of sacrifice (P \u3c 0.01). The body weight increase that had been observed in the mice pre-treated with Tregitope 167 was substantiated by a lower disease activity index and a decreased colon weight as compared to the diseased control group (P \u3c 0.01 and P \u3c 0.001, respectively). Immunohistochemical staining of the colonic tissues for CD4+ showed that inflammatory cell infiltrates were present in TNBS treated mice with or without administration with tregitope 167 and that these cellular infiltrates consisted mainly of CD4+ cells. For both TNBS treated groups CD4+ T cell infiltrates were observed in the sub-epithelial layer and the lamina propria. CD4+ T cell infiltrates were also present in the muscularis mucosa layer of the diseased control mice, but were absent in the Tregitope 167 treated group. Numerous Foxp3 positive cells were detected in the lamina propria and sub-epithelium of the colon sections from mice treated with Tregitope 167. Furthermore, the Foxp3 and glycoprotein A repetitions predominant markers were significantly increased in the CD4+ T lymphocyte population in the thymus of the mice pre-treated with adeno-associated virus serotype 5 (cytomegalovirus promoter-Tregitope 167), as cytomegalovirus promoter compared to lymphocyte populations in the thymus of diseased and the healthy control mice (P \u3c 0.05 and P \u3c 0.001, respectively). Conclusion: This study identifies adeno-associated virus-mediated delivery of regulatory T-cell epitope 167 as a novel anti-inflammatory approach with the capacity to decrease intestinal inflammation and induce long-term remission in inflammatory bowel disease

Teaching tolerance

Babies born with Pompe disease require life-long treatment with enzyme-replacement therapy (ERT). Despite the human origin of the therapy, recombinant human lysosomal acid α glucosidase (GAA, rhGAA), ERT unfortunately leads to the development of high titers of anti-rhGAA antibody, decreased effectiveness of ERT, and a fatal outcome for a significant number of children who have Pompe disease. The severity of disease, anti-drug antibody (ADA) development, and the consequences thereof are directly related to the degree of the enzyme deficiency. Babies born with a complete deficiency GAA are said to have cross-reactive immunologic material (CRIM)–negative Pompe disease and are highly likely to develop GAA ADA. Less frequently, GAA ADA develop in CRIM-positive individuals. Currently, GAA-ADA sero-positive babies are treated with a combination of immunosuppressive drugs to induce immunological tolerance to ERT, but the long-term effect of these regimens is unknown. Alternative approaches that might redirect the immune response toward antigen-specific tolerance without immunosuppressive agents are needed. Methods leading to the induction of antigen-specific regulatory T cells (Tregs), using peptides such as Tregitopes (T regulatory cell epitopes) are under consideration for the future treatment of CRIM-negative Pompe disease. Tregitopes are natural T cell epitopes derived from immunoglobulin G (IgG) that cause the expansion and activation of regulatory T cells (Treg). Teaching the immune system to tolerate GAA by co-delivering GAA with Tregitope peptides might dramatically improve the lives of CRIM-negative babies and could be applied to other enzyme replacement therapies to which ADA have been induced

Preoperative screening and prehabilitation strategies prior to ileocolic resection in patients with Crohn’s disease are not incorporated in routine care

Purpose: Recently, recommendations on perioperative care have been published to optimize postoperative outcomes in preoperative patients with inflammatory bowel disease. This study evaluated the current use of preoperative screening and prehabilitation strategies (PS) prior to elective ileocolic resection (ICR) in patients with Crohn’s disease (CD). Methods: Patients with CD who underwent an elective ICR were identified from a Dutch prospective cohort study. Primary endpoint was to evaluate to what extent IBD-relevant PS were applied in patients with CD prior to ICR according to the current recommendations. Results: In total, 109 CD patients were included. Screening of nutritional status was performed in 56% of the patients and revealed malnutrition in 46% of these patients. Of the malnourished patients, 46% was referred to a dietitian. Active smoking and alcohol consumption were reported in 20% and 28%; none of these patients were referred for a cessation program. A preoperative anemia was diagnosed in 61%, and ferritin levels were assessed in 26% of these patients. Iron therapy was started in 25% of the patients with an iron deficiency anemia. Exposure to corticosteroids at time of ICR was reported in 29% and weaned off in 3%. Consultation of a dietitian, psychologist, and physiotherapist was reported in 36%, 7%, and 3%. Physical fitness was assessed in none of the patients. Conclusion: PS are not routinely applied and not individually tailored in the preoperative setting prior to elective ICR in patients with CD. Prior to implementation, future research on the costs and effectiveness of PS on postoperative outcomes and quality of life is necessary.</p

Comorbidity, not patient age, is associated with impaired safety outcomes in vedolizumab- and ustekinumab-treated patients with inflammatory bowel disease-a prospective multicentre cohort study

Background: Few data are available on the effects of age and comorbidity on treatment outcomes of vedolizumab and ustekinumab in inflammatory bowel disease (IBD). Aims: To evaluate the association between age and comorbidity with safety and effectiveness outcomes of vedolizumab and ustekinumab in IBD. Methods: IBD patients initiating vedolizumab or ustekinumab in regular care were enrolled prospectively. Comorbidity prevalence was assessed using the Charlson Comorbidity Index (CCI). Association between age and CCI, both continuously assessed, with safety outcomes (any infection, hospitalisation, adverse events) during treatment, and effectiveness outcomes (clinical response and remission, corticosteroid-free remission, clinical remission combined with biochemical remission) after 52 weeks of treatment were evaluated. Multivariable logistic regression was used to adjust for confounders. Results: We included 203 vedolizumab- and 207 ustekinumab-treated IBD patients, mean age 42.2 (SD 16.0) and 41.6 (SD 14.4). Median treatment duration 54.0 (IQR 19.9-104.0) and 48.4 (IQR 24.4-55.1) weeks, median follow-up time 104.0 (IQR 103.1-104.0) and 52.0 weeks (IQR 49.3-100.4). On vedolizumab, CCI associated independently with any infection (OR 1.387, 95% CI 1.022-1.883, P = 0.036) and hospitalisation (OR 1.586, 95% CI 1.127-2.231, P = 0.008). On ustekinumab, CCI associated independently with hospitalisation (OR 1.621, 95% CI 1.034-2.541, P = 0.035). CCI was not associated with effectiveness, and age was not associated with any outcomes. Conclusions: Comorbidity - but not age - is associated with an increased risk of hospitalisations on either treatment, and with any infection on vedolizumab. This underlines the importance of comorbidity assessment and safety monitoring of IBD patients

Gene and cell therapy based treatment strategies for inflammatory bowel diseases

Inflammatory bowel diseases (IBD) are a group of chronic inflammatory disorders most commonly affecting young adults. Currently available therapies can result in induction and maintenance of remission, but are not curative and have sometimes important side effects. Advances in basic research in IBD have provided new therapeutic opportunities to target the inflammatory process involved. Gene and cell therapy approaches are suitable to prevent inflammation in the gastrointestinal tract and show therefore potential in the treatment of IBD. In this review, we present the current progress in the field of both gene and cell therapy and future prospects in the context of IBD. Regarding gene therapy, we focus on viral vectors and their applications in preclinical models. The focus for cell therapy is on regulatory T lymphocytes and mesenchymal stromal cells, their potential for the treatment of IBD and the progress made in both preclinical models and clinical trials

Neutralizing antibodies against adeno-associated viruses in inflammatory bowel disease patients: implications for gene therapy

Inflammatory bowel diseases (IBDs) are comprised of two major disorders: Crohn's disease (CD) and ulcerative colitis (UC). No curative treatment options are available, but gene therapy may offer an alternative therapeutic approach. For this a safe and reliable vector is needed. The adeno-associated viruses (AAV) have attracted considerable interest as gene therapy vectors. However, neutralizing antibodies (nAb's) made in response to wildtype AAV have been associated with a partial to complete block of transduction in case of reexposure. Therefore, and in order to define AAV vector candidates to treat IBD patients, we characterized preexisting humoral responses to AAV in this population. We measured circulating antibodies against AAV serotypes 1, 2, 3, 4, 5, 6, and 8 using a previously established virus neutralization assay. In all, 100 healthy donors and 200 IBD patient's serum samples (101 CD and 99 UC) were analyzed. A significant difference was detected in the prevalence of nAb's for AAV types 1, 5, 6, and 8 between the healthy donors and the patient population. Furthermore, various disease phenotypic characteristics correlated with the prevalence of nAb's to all the serotypes studied. Our study establishes a foundation for the development of an AAV-based gene therapy approach as a novel treatment for IBD. Furthermore, we show a relationship between disease phenotype in IBD patients and the humoral immune response to AA

Quality of web-based information on inflammatory bowel diseases

BACKGROUND:: The Internet is the largest source of health information and is widely used by inflammatory bowel disease (IBD) patients. As information is largely unregulated, our objective was to evaluate the quality, readability, accuracy, and accessibility of the information concerning IBD available on the World Wide Web. METHODS:: The phrases "inflammatory bowel disease," "Crohn's disease," and "Ulcerative Colitis" were entered separately as search terms into the 6 most commonly used search engines. Sites were categorized as institutional, pharmaceutical, nonpharmaceutical commercial sites, charitable, support, or alternative medicine. Websites were evaluated for content quality using the validated DISCERN rating instrument. Readability was graded by the Flesch Reading Ease and the Flesch-Kincaid Grade Level score. RESULTS:: Of the 76 websites evaluated by DISCERN, 43% of the sites were rated as excellent to good and 57% as fair to poor. Alternative medicine sites scored significant lower (P > 0.05) than institutional, pharmaceutical, and nonpharmaceutical commercial sites. There was no relation between a rating score and the position of a website on the search engine ranking. The median Flesch Reading Ease Score was 41.65 (range, 2.6-77.7) and 11.85 (range, 6.2-21.1) for the Flesch-Kincaid Grade Level. CONCLUSIONS:: The quality of websites containing information on IBD varies widely. Most of the online material available is too difficult to comprehend for a substantial portion of the patient population, and good quality information may be beyond reach of the average information seeker. Inflamm Bowel Dis 200

Synthesis of Asparagine Derivatives Harboring a Lewis X Type DC-SIGN Ligand and Evaluation of their Impact on Immunomodulation in Multiple Sclerosis

The protein myelin oligodendrocyte glycoprotein (MOG) is a key component of myelin and an autoantigen in the disease multiple sclerosis (MS). Post-translational N-glycosylation of Asn31 of MOG seems to play a key role in modulating the immune response towards myelin. This is mediated by the interaction of Lewis-type glycan structures in the N-glycan of MOG with the DC-SIGN receptor on dendritic cells (DCs). Here, we report the synthesis of an unnatural Lewis X (LeX)-containing Fmoc-SPPS-compatible asparagine building block (SPPS=solid-phase peptide synthesis), as well as asparagine building blocks containing two LeX-derived oligosaccharides: LacNAc and Fucα1-3GlcNAc. These building blocks were used for the glycosylation of the immunodominant portion of MOG (MOG31-55) and analyzed with respect to their ability to bind to DC-SIGN in different biological setups, as well as their ability to inhibit the citrullination-induced aggregation of MOG31-55. Finally, a cytokine secretion assay was carried out on human monocyte-derived DCs, which showed the ability of the neoglycopeptide decorated with a single LeX to alter the balance of pro- and anti-inflammatory cytokines, inducing a tolerogenic response