Neuroimmune Modulation Through Vagus Nerve Stimulation Reduces Inflammatory Activity in Crohn's Disease Patients: A Prospective Open-label Study.

BACKGROUND AND AIMS: Crohn's disease [CD] is a debilitating, inflammatory condition affecting the gastrointestinal tract. There is no cure and sustained clinical and endoscopic remission is achieved by fewer than half of patients with current therapies. The immunoregulatory function of the vagus nerve, the 'inflammatory reflex', has been established in patients with rheumatoid arthritis and biologic-naive CD. The aim of this study was to explore the safety and efficacy of vagus nerve stimulation in patients with treatment-refractory CD, in a 16-week, open-label, multicentre, clinical trial. METHODS: A vagus nerve stimulator was implanted in 17 biologic drug-refractory patients with moderately to severely active CD. One patient exited the study pre-treatment, and 16 patients were treated with vagus nerve stimulation [4/16 receiving concomitant biologics] during 16 weeks of induction and 24 months of maintenance treatment. Endpoints included clinical improvement, patient-reported outcomes, objective measures of inflammation [endoscopic/molecular], and safety. RESULTS: There was a statistically significant and clinically meaningful decrease in CD Activity Index at Week 16 [mean ±â€…SD: -86.2 ±â€…92.8, p = 0.003], a significant decrease in faecal calprotectin [-2923 ±â€…4104, p = 0.015], a decrease in mucosal inflammation in 11/15 patients with paired endoscopies [-2.1 ±â€…1.7, p = 0.23], and a decrease in serum tumour necrosis factor and interferon-γ [46-52%]. Two quality-of-life indices improved in 7/11 patients treated without biologics. There was one study-related severe adverse event: a postoperative infection requiring device explantation. CONCLUSIONS: Neuroimmune modulation via vagus nerve stimulation was generally safe and well tolerated, with a clinically meaningful reduction in clinical disease activity associated with endoscopic improvement, reduced levels of faecal calprotectin and serum cytokines, and improved quality of life.

Inflammatory Bowel Disease and Risk of Colorectal Polyps: A Nationwide Population-Based Cohort Study From Sweden.

BACKGROUND: Inflammatory bowel disease [IBD] has been linked to an increased risk of colorectal neoplasia. However, the types and risks of specific polyp types in IBD are less clear. METHODS: We identified 41 880 individuals with IBD (Crohn's disease [CD: n = 12 850]; ulcerative colitis [UC]: n = 29 030]) from Sweden matched with 41 880 reference individuals. Using Cox regression, we calculated adjusted hazard ratios [aHRs] for neoplastic colorectal polyps [tubular, serrated/sessile, advanced and villous] defined by histopathology codes. RESULTS: During follow-up, 1648 [3.9%] IBD patients and 1143 [2.7%] reference individuals had an incident neoplastic colorectal polyp, corresponding to an incidence rate of 46.1 and 34.2 per 10 000 person-years, respectively. This correlated to an aHR of 1.23 (95% confidence interval [CI] 1.12-1.35) with the highest HRs seen for sessile serrated polyps [8.50, 95% CI 1.10-65.90] and traditional serrated adenomas [1.72, 95% CI 1.02-2.91]. aHRs for colorectal polyps were particularly elevated in those diagnosed with IBD at a young age and at 10 years after diagnosis. Both absolute and relative risks of colorectal polyps were higher in UC than in CD [aHRs 1.31 vs 1.06, respectively], with a 20-year cumulative risk difference of 4.4% in UC and 1.5% in CD, corresponding to one extra polyp in 23 patients with UC and one in 67 CD patients during the first 20 years after IBD diagnosis. CONCLUSIONS: In this nationwide population-based study, there was an increased risk of neoplastic colorectal polyps in IBD patients. Colonoscopic surveillance in IBD appears important, especially in UC and after 10 years of disease.

Tumour necrosis factor inhibitors in Crohn's disease and the effect on surgery rates.

AIM: Surgery is an important therapeutic option for Crohn's disease. The need for first bowel surgery seems to have decreased with the introduction of tumour necrosis factor inhibitors (TNFi; adalimumab or infliximab). However, the impact of TNFi on the need for intestinal surgery in Crohn's disease patients irrespective of prior bowel resection is not known. The aim of this work is to compare the incidence of bowel surgery in Crohn's disease patients who remain on TNFi treatment versus those who discontinue it. METHOD: We performed a nationwide register-based observational cohort study in Sweden of all incident and prevalent cases of Crohn's disease who started first-line TNFi treatment between 2006 and 2017. Patients were categorized according to TNFi treatment retention less than or beyond 1 year. The study cohort was evaluated with regard to incidence of bowel surgery from 12 months after the first ever TNFi dispensation. RESULTS: We identified 5003 Crohn's disease patients with TNFi exposure: 3748 surgery naïve and 1255 with bowel surgery prior to TNFi initiation. Of these patients, 7% (n = 353) were subjected to abdominal surgery during the first 12 months after the start of TNFi and were subsequently excluded from the main analysis. A majority (62%) continued TNFi for 12 months or more. Treatment with TNFi for less than 12 months was associated with a significantly higher surgery rate compared with patients who continued on TNFi for 12 months or more (hazard ratio 1.26, 95% CI 1.09-1.46; p = 0.002). CONCLUSION: Treatment with TNFi for less than 12 months was associated with a higher risk of bowel surgery in Crohn's disease patients compared with those who continued TNFi for 12 months or more.

[Overview of immune-related side effects from immune checkpoint inhibitors. Part 1: Gastrointestinal, lung and kidney toxicity]. / Immunrelaterade biverkningar i tarm, lever, lungor och njurar.

In the past decade, immunotherapy with checkpoint inhibitors has revolutionized the field of oncology. Checkpoint inhibitors have been approved for several types of cancer and thousands of patients in Sweden now receive oncological immunotherapy annually. Immune-related side effects are common and can occur in almost any organ. These side effects are different from those that occur with traditional oncological treatments. The side effects are usually mild, but can be serious and even lethal. In a short time, health care providers have had to readjust to be able to handle these side effects. Early and correct diagnosis of immune-related side effects, proper management and a multidisciplinary approach is crucial. Here, we give an overview of the presentation, diagnosis and treatment of immune-related side effects, with emphasis of those occurring in gastrointestinal organs, lungs and kidneys.

Older age is a risk factor for inadequate energy intake during acute, severe IBD and is associated with shorter time to relapse.

BACKGROUND: Effects of nutritional intake on inflammatory bowel disease (IBD) flare resolution are unknown. We hypothesised that nutritional factors during hospitalisation for acute severe IBD are associated with risk of subsequent relapse. We also studied risk factors for inadequate energy intake. METHODS: Patients admitted to the Karolinska Hospital Gastroenterology ward with IBD flare during 2015-2016 were retrospectively identified. In total, 91 patients were included. Data on nutrition, disease factors, inflammatory markers, and daily energy requirement were extracted. Requirement of new systemic steroid prescription, intensification of biological therapy, readmission, surgery, and calprotectin level were individually used as proxies for disease relapse. Follow-up was one year after discharge. Adjustments for age and sex were made where appropriate. RESULTS: Overall, 19%, 31%, and 45% of patients had days with energy intake <30, <50, and <70% of calculated requirement. Older age was associated with a higher number of days with energy intake <30, <50, and <70% of calculated requirement (regression coefficient 0.03, 0.04, 0.06 respectively, p = .012, .017, .008). The number of days with energy intake <30 and <70% of the calculated requirement and the length of the hospitalisation were associated with shorter time to new steroid prescription (hazard ratio 1.3, 1.1, 1.04 respectively, p = .016, .034, .011). CRP and calprotectin were not associated with relapse. CONCLUSION: Older age is a predictor of inadequate energy intake during hospitalisation for acute severe IBD. Inadequate energy intake adjusted for age and sex during IBD flare was better predictor of time to the next steroid-requiring relapse than inflammatory markers.

Vagotomy and subsequent risk of inflammatory bowel disease: a nationwide register-based matched cohort study.

BACKGROUND: The vagus nerve provides essential parasympathetic innervation to the gastrointestinal system and is known to have anti-inflammatory properties. AIMS: To explore the relationship between vagotomy and the risk of inflammatory bowel disease (IBD) and its major categories: Crohn's disease (CD) and ulcerative colitis (UC). METHODS: A matched cohort comprising 15 637 patients undergoing vagotomy was identified through the Swedish Patient Register from 1964 to 2010. Each vagotomised patient was matched for birth year and gender with 40 nonvagotomised individuals on the date of vagotomy. We estimated hazard ratios (HRs) and 95% confidence intervals (CIs) for IBD using flexible parametric models adjusted for matching variables, year of vagotomy, birth country, chronic obstructive pulmonary disease and comorbidity index. RESULTS: We observed 119 (0.8%) patients with vagotomy developed IBD compared to 3377 (0.5%) IBD cases in nonvagotomised individuals. The crude incidence of IBD (per 1000 person-years) was 0.38 for vagotomised patients and 0.25 for nonvagotomised individuals. We observed a time-dependent elevated risk of IBD associated with vagotomy, for instance, the HR (95% CI) was 1.80 (1.40-2.31) at year 5 and 1.49 (1.14-1.96) at year 10 post-vagotomy. The association appeared to be stronger for truncal than selective vagotomy and limited to CD (HR was 3.63 [1.94-6.80] for truncal and 2.06 [1.49-2.84] for selective vagotomy) but not UC (1.36 [0.71-2.62] for truncal and 1.25 [0.95-1.63] for selective vagotomy). CONCLUSIONS: We found a positive association between vagotomy and later IBD, particularly for CD. The finding indirectly underlines the beneficial role of the vagal tone in IBD.

Sustained clinical benefit, improved quality of life, and reduced intestinal surgery from maintenance infliximab treatment in inflammatory bowel disease.

Objectives: Anti-TNF treatment is established for patients with severe inflammatory bowel disease (IBD) refractory to conventional medication. However, long-term real-life observations are limited. We have monitored 200 patients with primary response to infliximab (Remicade®).Methods: Patients with either Crohn's disease (CD) or ulcerative colitis (UC) who started IFX and had clinical response at 1 year were prospectively followed. C-reactive protein (CRP), albumin, fecal calprotectin (FCP), Harvey Bradshaw index (HBI) in CD cases, and Quality of Life index were monitored. Concomitant medications, surgery and hospitalisation were assessed.Results: Out of the 200 patients, 164 suffered from CD. Median disease duration was 5.0 (0.2-44.0) years and the observation time was 3.4 (1.0-13.9) years. Steroid use was reduced from 51% to 10%. HBI in CD patients decreased from 8.0 ± 0.40 to 2.7 ± 0.26. Disease activity in UC patients was only assessed by biochemical markers. CRP decreased from 29.0 ± 6.2 to 8.0 ± 7.1 mg/L. FCP showed a decrease from 1918 (1837) to 191 (646) mg/kg. Hospitalization showed similar tendency and quality of life was improved. Twenty-seven percent had been operated before IFX introduction compared to 11% during the observation period. Loss of response was seen in 42 patients, of which 20 patients needed intestinal surgery.Conclusion: Two-thirds of the patients demonstrated stable clinical benefit from maintenance IFX. The results show steroid-sparing efficacy as well as improved quality of life and reduced need for surgery.

Swedish Inflammatory Bowel Disease Register (SWIBREG) - a nationwide quality register.

Background: Inflammatory bowel disease (IBD) is a chronic, inflammatory relapsing disease with increasing incidence. IBD research and long-term follow-up of patients have, however, been hampered by lack of detailed data on disease phenotype, patient-reported outcome measures, Physician Global Assessment, disease activity, and hospital-administered drugs. Aim: To review the Swedish IBD quality register (SWIBREG). Methods: Review of SWIBREG including questionnaire data from users and patients. Results: SWIBREG was launched in 2005, and as of April 2019, contains 46,400 patients with IBD (Crohn's disease: n = 15,705, ulcerative colitis: n = 21,540, IBD unclassified and other colitis (including e.g., microscopic colitis): n = 9155). Of these IBD patients, 7778 had been diagnosed in childhood (16.8%). Earlier research has shown that combining SWIBREG and the Swedish National Patient Register (NPR) yields a positive predictive value of 100% (95%CI = 95-100%) for having a diagnosis of IBD. Moreover, out of all patients in the NPR with a diagnosis of IBD plus either IBD-related surgery or immunomodulatory/biological treatment during the past 18 months, SWIBREG covers 59.0%. SWIBREG records not only information on conventional therapies but also on biological treatment, surgery, smoking, disease activity, patient-reported outcome measures (PROMs), and patient-experienced measures (PREMs). Data are presented through a graphical decision support system. Conclusion: SWIBREG benefits patients with IBD, and offers an ideal opportunity for healthcare personnel and researchers to examine disease phenotype and activity, PROMs/PREMs, and hospital-administered drugs in patients with IBD.

Exclusive Enteral Nutrition: Clinical Effects and Changes in Mucosal Cytokine Profile in Pediatric New Inflammatory Bowel Disease.

Exclusive Enteral Nutrition (EEN) is the first-line treatment in children with Crohn's disease (CD) for induction of remission. However, the mode of action remains conjectural. The aim of this study was to investigate whether the effect of EEN is paralleled by changes in the mucosal cytokine profiles (MCP). Twelve children with new onset inflammatory bowel disease (IBD) received induction treatment with a polymeric EEN. We assessed clinical, endoscopic and histologic scoring before and after EEN. Twelve colonic cytokines were analyzed by Polymerase Chain Reaction (PCR) in six of the IBD patients at onset and after EEN as well as in six non-IBD control children at the diagnostic colonoscopy. Twelve children completed 6 weeks of EEN, except from one child who completed 4 weeks. At the control colonoscopy, 83% were in complete clinical remission. Changes were found in the MCPs of individual patients after EEN. In particular, children with IBD showed significantly higher values of Interleukin (IL)-12ß (p = 0.008) and IL-23α (p = 0.02) compared to non-IBD controls at the diagnostic colonoscopy. Furthermore, an overall change in proinflammatory cytokines was noted in the IBD-group after treatment. Further studies are warranted to understand the role of EEN in MCP.

Towards improved control of inflammatory bowel disease.

Inflammatory bowel disease (IBD) is characterized by activation of both the innate and adaptive immune system in genetically susceptible individuals, resulting in chronic intestinal inflammation. The triggers that initiate and perpetuate this continuous inflammation are the subject of much speculation and research, although the central role of the intestinal microbiota is recognized, and is even a target for treatment in some circumstances. The mainstay of modern IBD treatment is suppression of the immune response towards as yet unspecified antigens, and conventional therapy includes corticosteroids, 5-aminosalicylic acid (5-ASA), thiopurines and methotrexate. Reducing activity of specific mediators has proven efficacious, including adhesion molecules, such as the gut-homing integrin α4 ß7 expressed on the surface of circulating immune cells, and cytokines, such as tumour necrosis factor α (TNF-α). This has been achieved using biologic agents including monoclonal antibodies. Recent discoveries in immunology and neuroscience have revealed that signals in the peripheral nervous system regulate inflammation, including levels of TNF-α. The understanding of the mechanisms of the neuro-immune communication involved in inflammation control in the gut is evolving, but is as yet incomplete. Clinical studies using implanted vagus nerve stimulators for treatment of IBD show encouraging results. Accordingly, the neural reflex control of inflammation is emerging as a potential therapeutic target in treatment of IBD. Here, we review current therapeutic options and neural reflex control of gut immunity in the context of intestinal inflammation.

Mucosal Cytokine Profiles After Induction Therapy With Granulocyte/Monocyte Apheresis in New-onset Inflammatory Colitis.

Granulocyte/monocyte apheresis (GMA) selectively removes circulating granulocytes and monocytes; important producers of proinflammatory cytokines. Seven children with new-onset inflammatory bowel disease (IBD) colitis were treated with GMA together with mesalazine, and had significant decreases in Pediatric UC Activity Index (P = 0.018) and Mayo endoscopic score (P = 0.013). We investigated the colonic mucosal cytokine profiles (analyzed with real-time polymerase chain reaction), before and after induction treatment, and in 6 non-IBD controls. Significant decreases were seen in Colony Stimulating Factor 2 (P = 0.018), tumor necrosis factor-α (P = 0.028), interleukin (IL)-23α (P = 0.043), IL-1ß (P = 0.028), IL-36γ (P = 0.018), IL-10 (P = 0.028), and transforming growth factor beta 1 (P = 0.043) after treatment. In 6 non-IBD controls there were significantly lower levels of IL-12ß (P = 0.023) and IL-23α (P = 0.046) compared to the patients with IBD at onset, and IL-22 (P = 0.088) and IL-36γ (P = 0.062) showed lower values without reaching significant differences. We speculate that the decreases in colonic mucosal cytokine profiles after treatment may explain the observed clinical efficacy in the GMA-treated children with IBD.

Granulocyte and Monocyte Apheresis for Induction of Remission in Children With New-Onset Inflammatory Bowel Colitis.

OBJECTIVE: The aim of the study was to analyze the effect of granulocyte and monocyte apheresis (GMA) with mesalazine for induction of remission in pediatric patients with newly onset chronic inflammatory bowel disease (IBD) colitis. METHODS: Thirteen pediatric patients with newly onset extensive IBD colitis were investigated per the ECCO/ESPGHAN IBD protocol. Of these 13, 12 received 10 treatments with Adacolumn (ADA) during a median of 6.25 weeks in combination with low-to-moderate doses of mesalazine, which was continued after apheresis. A control colonoscopy was performed 12 to 16 weeks after GMA treatment. Primary outcomes were mucosal healing (Mayo endoscopic score) and histopathologic grading of biopsies. A secondary outcome was disease activity as measured by the Pediatric Ulcerative Colitis Activity Index. RESULTS: Twelve children (6 girls) with a median age of 14.6 years and a median duration of symptoms at diagnosis of 3.2 months received all planned 10 treatment sessions with ADA. Ten of 12 patients had pancolitis and 2 of 12 extensive colitis. A final diagnosis, however, indicated ulcerative colitis in 10 children and Crohn disease in 2 children. At control colonoscopy, 8 of 12 children were in clinical remission and the Mayo endoscopic score showed significant improvement in 9 of 12 patients (P = 0.006). Complete microscopic remission, according to the Geboes score, was observed in 2 patients. CONCLUSIONS: In this small study GMA for induction of remission of newly onset pediatric IBD colitis was effective in 8 of 12 patients. Further controlled studies are warranted to confirm the efficacy of this treatment model.

Randomised, Double-blind, Placebo-controlled Trial of CCR9-targeted Leukapheresis Treatment of Ulcerative Colitis Patients.

BACKGROUND AND AIMS: Ulcerative colitis patients display increased numbers of circulating pro-inflammatory monocyte human leukocyte antigen-DR [HLA-DRhi] monocytes expressing high levels of the gut-homing C-C chemokine receptor 9 [CCR9] and tumour necrosis factor [TNF]-α. The aim of this first-in-human, double-blind, randomised, placebo-controlled trial was to evaluate selective removal of circulating CCR9-expressing monocytes by leukapheresis in patients with moderate to severe ulcerative colitis, with regards to safety, tolerability, and immunological response. METHODS: Patients with ulcerative colitis were treated every second day with leukapheresis during five sessions with a C-C chemokine ligand 25 [CCL25; CCR9 ligand] column or a placebo column. RESULTS: No major safety concerns were raised and the procedure was well tolerated. Pro-inflammatory HLA-DRhi cells decreased significantly in the active treatment group [p = 0.0391] whereas no statistically significant change was seen in the placebo group [p = 0.4688]. There was a significant decrease of HLA-DRhi monocytes in the active group compared with the placebo group when corrected for the imbalance in weight between the groups [p = 0.0105]. Mayo score decreased in the active group [p = 0.0156] whereas the change in the placebo group was not significant [p = 0.1250]. Mayo score ≤ 3 was observed in five out of 14 patients [35.7%] in the active group compared with one out of eight [12.5%] receiving placebo. The number of responders in the active treatment group was eight out of 14 patients [57.1%], whereas in the corresponding placebo group three out of eight patients [37.5%] responded to placebo. A dose-response correlation was observed between the blood volume processed and clinical outcome. CONCLUSION: This clinical induction trial using CCL25-tailored leukapheresis demonstrates a safe and effective removal of activated monocytes with a clinical effect in patients with ulcerative colitis.

Long-term effectiveness of vedolizumab in inflammatory bowel disease: a national study based on the Swedish National Quality Registry for Inflammatory Bowel Disease (SWIBREG).

OBJECTIVES: Clinical trials have demonstrated the efficacy of vedolizumab in inflammatory bowel disease (IBD). However, these findings may not reflect the clinical practice. Therefore, we aimed to describe a vedolizumab-treated patient population and assess long-term effectiveness. MATERIALS AND METHODS: Patients initiating vedolizumab between 1 June 2014 and 30 May 2015 were identified through the Swedish National Quality Registry for IBD. Prospectively collected data on treatment and disease activity were extracted. Clinical remission was defined as Patient Harvey Bradshaw index <5 in Crohn's disease (CD) and Patient Simple Clinical Colitis Activity index <3 in ulcerative colitis (UC). RESULTS: Two-hundred forty-six patients (147 CD, 92 UC and 7 IBD-Unclassified) were included. On study entry, 86% had failed TNF-antagonist and 48% of the CD patients had undergone ≥1 surgical resection. After a median follow-up of 17 (IQR: 14-20) months, 142 (58%) patients remained on vedolizumab. In total, 54% of the CD- and 64% of the UC patients were in clinical remission at the end of follow-up, with the clinical activity decreasing (p < .0001 in both groups). Faecal-calprotectin decreased in CD (p < .0001) and in UC (p = .001), whereas CRP decreased in CD (p = .002) but not in UC (p = .11). Previous anti-TNF exposure (adjusted HR: 4.03; 95% CI: 0.96-16.75) and elevated CRP at baseline (adjusted HR: 2.22; 95% CI: 1.10-4.35) seemed to be associated with discontinuation because of lack of response. Female sex was associated with termination because of intolerance (adjusted HR: 2.75; 95% CI: 1.16-6.48). CONCLUSION: Vedolizumab-treated patients represent a treatment-refractory group. A long-term effect can be achieved, even beyond 1 year of treatment.

Trough s-infliximab and antibodies towards infliximab in a cohort of 79 IBD patients with maintenance infliximab treatment.

BACKGROUND AND AIMS: The anti-TNF antibody infliximab is effective in inducing remission in Crohn's disease as well as in ulcerative colitis and many patients are treated for several years with sustained clinical remission. However, the role of monitoring s-infliximab and antibodies towards infliximab during maintenance treatment remains unclear. Our aim was to correlate serum drug levels and antibodies to clinical activity, CRP, albumin and concomitant immunosuppression in a cohort on maintenance infliximab treatment. METHODS: We included 79 patients with Crohn's disease or ulcerative colitis who had responded to infliximab and received maintenance treatment (4-69 infusions) in this retrospective study. Infliximab levels and antibodies towards the drug were analyzed with in-house-developed ELISA assays. RESULTS: The mean s-infliximab was significantly higher in patients in remission (4.1µg/mL) as compared with disease flare (mean 1.8µg/mL); p<0.001. The s-infliximab showed a significant negative correlation with Harvey-Bradshaw index (r=-0.21; p<0.05). Serum-infliximab progressively decreased with the number of accumulated infusions (p<0.05). In patients with undetectable trough levels, 55% of the patients with concomitant immunosuppressive were positive for antibodies against infliximab, as compared with 94% of patients on monotherapy. Patients with undetectable serum-infliximab were in clinical remission at 25% of the visits. CONCLUSIONS: The trough level 4.1µg/mL may serve as cut-off for clinical remission. Drug trough levels decreased during treatment and almost all patients with undetectable s-infliximab and monotherapy had developed antibodies against the drug.

Naïve T cells correlate with mucosal healing in patients with inflammatory bowel disease.

BACKGROUND: In previous studies, adaptive immune responses involving T-helper cells have been shown to play an important role in inflammatory bowel diseases (IBDs). METHODS: The aim of this study was to investigate any correlation between the degree of mucosal inflammation and the phenotype of gut-infiltrating T-helper cells. Biopsies from intestinal mucosa were obtained and intestinal T cells were analyzed with regard to activity and maturation markers. Patients with active colitis (39 with Crohn's disease and 47 with ulcerative colitis) were included and treated with corticosteroids, biologicals or leukocytapheresis. Flow cytometry was used to analyze activation marker expression on gut-infiltrating T-helper cells. RESULTS: Mucosal healing was reflected by almost 100% increase of CD62L expression in mucosal T cells in patients in remission compared to those with active inflammation (p < 0.01). The frequency of mucosal-naïve CD4(+)CD45RA(+) T cells was reduced by 50% in mucosa displaying remission (5.3% compared to 12% of the total amount and CD4(+) T cells, p < 0.001). Surprisingly, the proportion of early activated T-helper cells (CD4(+)CD69(+)) did not differ between mucosa in remission and non-remission (43% and 42%, respectively). Moreover, no change in memory T-helper cells (CD4(+)CD45RO(+)) was observed (64% compared to 66%). The findings were independent of diagnosis (Crohn's disease or ulcerative colitis) or mode of treatment. CONCLUSION: This study suggests that a reduced recruitment of naïve T-helper cells and increased frequency of T-helper cells with lymph node homing marker expression reflect mucosal healing in IBD. Surprisingly, the degree of activation of mucosal T-helper cells did not correlate with disease remission.

Treatment of inflammatory bowel disease by chemokine receptor-targeted leukapheresis.

Leukapheresis removes circulating leukocytes en route to the target organ. Hitherto unspecific matrixes have been used to remove leukocytes in inflammatory bowel disease (IBD). This report describes a novel selective leukapheresis column based on chemokine-chemokine receptor interaction. We found an increased expression of the gut homing chemokine receptor CCR9 on CD14(+) monocytes and on CD3(+) T lymphocytes from IBD patients. Biologically active CCL25 was coupled to a Sepharose matrix and demonstrated to selectively remove CCR9-expressing cells leaving other cell populations largely unaffected. A patient with active ulcerative colitis, was subjected to CCL25-column leukapheresis. Four days after treatment, he experienced clinical improvement and stable disease improvement ensued. The study illustrates that specific cells can be targeted using high affinity interactions, i.e., CCL25-CCR9 interactions to remove pathogenic gut-homing cells. Leukapheresis using the bCCL25 column should be investigated in a clinical phase I trial of patients with inflammatory bowel disease.

HLA-DR(hi) and CCR9 Define a Pro-Inflammatory Monocyte Subset in IBD.

OBJECTIVES: It has been demonstrated that circulating monocytes relocate to the intestinal mucosa during intestinal inflammation, but the phenotype and inflammatory mechanisms of these monocytes remain poorly understood. Here, we have investigated blood monocytes expressing high levels of HLA-DR and CCR9 in patients with inflammatory bowel disease (IBD). METHODS: Fifty-one patients with mild to severe ulcerative colitis (UC; n=31; UC-DAI 3-12) or Crohn's disease (CD; n=20; Harvey-Bradshaw indices (HBI) 2-16) were included together with 14 controls, during IBD therapy for four consecutive weeks. The frequency of CD14(+)HLA-DR(hi) monocytes was monitored weekly in peripheral blood, using flow cytometry. The surface phenotype and cytokine profile of these monocytes were established using flow cytometry and real-time PCR. Clinical parameters were assessed weekly in all patients. RESULTS: The frequency of circulating CD14(+)HLA-DR(hi) monocytes was significantly higher in IBD patients with moderate to severe disease compared with healthy controls (P<0.001). During treatment with corticosteroids and granulocyte/monocyte apheresis, the proportion of circulating CD14(+)HLA-DR(hi) monocytes was significantly reduced. CD14(+)HLA-DR(hi) monocytes produced high levels of inflammatory mediators, such as tumor necrosis factor (TNF)-α, and expressed the gut-homing receptor CCR9. Furthermore, we found that the CCR9 ligand, CCL25/TECK, was expressed at high levels in the colonic mucosa in IBD patients with active disease. CONCLUSIONS: CD14(+)HLA-DR(hi) blood monocytes were increased in patients with active IBD. These monocytes exhibit a pro-inflammatory, gut-homing phenotype with regard to their TNF-α production and expression of CCR9. Our results suggest that these monocytes are important in mediating intestinal inflammation, and provide potential therapeutic targets in IBD.

The sentinel node technique is useful for studies of intestinal immunology in inflammatory bowel disease patients.

OBJECTIVE: Mesenteric lymph nodes may play a crucial role in the pathogenesis of human inflammatory bowel disease. We have used the sentinel node technique to analyze mesenteric lymph nodes draining inflammatory lesions sentinel nodes and corresponding site of inflamed bowel in patients with ulcerative colitis or Crohn's disease. METHODS: Thirty-two patients undergoing surgical treatment of inflammatory bowel disease were included. Sentinel nodes were identified intraoperatively. The T cells were harvested from the mesenteric lymph nodes and characterized by flow cytometry. RESULTS: The distribution of CD4CD62L (homing-marked) and CD4CD69 (activated) T cells was studied in mesenteric lymph nodes draining inflammation, nodes draining normal intestine, blood, and mucosa. The turnover of T cells was markedly increased in the lymph nodes connected to inflammatory segments. The immunologic activity of the sentinel lymph nodes correlated with the degree of intestinal inflammation. CONCLUSION: Mesenteric sentinel nodes provide important information about locoregional immunology and pathogenesis in inflammatory bowel disease.