Alterations of the human gut microbiome in multiple sclerosis

The gut microbiome plays an important role in immune function and has been implicated in several autoimmune disorders. Here we use 16S rRNA sequencing to investigate the gut microbiome in subjects with multiple sclerosis (MS, n=60) and healthy controls (n=43). Microbiome alterations in MS include increases in Methanobrevibacter and Akkermansia and decreases in Butyricimonas, and correlate with variations in the expression of genes involved in dendritic cell maturation, interferon signalling and NF-kB signalling pathways in circulating T cells and monocytes. Patients on disease-modifying treatment show increased abundances of Prevotella and Sutterella, and decreased Sarcina, compared with untreated patients. MS patients of a second cohort show elevated breath methane compared with controls, consistent with our observation of increased gut Methanobrevibacter in MS in the first cohort. Further study is required to assess whether the observed alterations in the gut microbiome play a role in, or are a consequence of, MS pathogenesis

Spatial Evolution of Histologic and Endoscopic Healing in the Left and Right Colon in Patients With Ulcerative Colitis

Background and aimsDespite increasing interest in histologic remission as a treatment target in ulcerative colitis (UC), the accuracy of histologic findings in left colon in detecting pancolonic histologic remission is unknown.MethodsIn a retrospective cohort study of patients with endoscopically active pancolitis undergoing treat-to-target interventions, we evaluated the diagnostic accuracy of left-sided (distal to splenic flexure) histologic and endoscopic findings on colonoscopy for detecting histologic and endoscopic healing elsewhere in the colon.ResultsOf 86 patients with moderate to severely active pancolitis who underwent 2 consecutive colonoscopies during treat-to-target interventions, 38% and 51% achieved histologic and endoscopic remission, respectively. Substantial agreement (kappa, 0.67; 95% confidence interval (CI), 0.51-0.83) was observed in histologic findings between left and right colon on follow-up colonoscopy. Histologic, and endoscopic, findings in left colon showed excellent accuracy in detecting pancolonic histologic remission (area under the curve (AUC), 0.96 [95% CI, 0.93-1.0]; misclassification rate, 5.9%), histologic normalization (AUC, 1.0, 0%), endoscopic improvement (AUC, 0.95 [0.96-1.0], 3.5%) and endoscopic remission (AUC, 0.98 [0.96-1.00], 5.8%), respectively.ConclusionsIn patients with active pancolitis undergoing treat-to-target interventions, histologic and endoscopic findings in the left colon on colonoscopy have excellent accuracy for detecting pancolonic histologic remission, histologic normalization, endoscopic improvement, and endoscopic remission. Flexible sigmoidoscopy may suffice for monitoring histologic and endoscopic activity in patients with pancolitis

Incremental Benefit of Achieving Endoscopic and Histologic Remission in Patients With Ulcerative Colitis: A Systematic Review and Meta-Analysis

Background & aimsClinical remission, defined by a composite of patient reported outcomes and Mayo endoscopy subscore (MES) 0 or 1 is a recommended treatment target in patients with ulcerative colitis (UC). We estimated whether incorporating more rigorous remission definitions, of endoscopic remission (MES 0) and histologic remission, affects risk of relapse.MethodsThrough a systematic review, we identified cohort studies in adults with UC in clinical remission that reported a minimum 12-month risk of clinical relapse, based on MES (0 vs 1) and/or histologic disease activity, in patients with endoscopic remission. Using random effects meta-analysis, we calculated relative and absolute risk of clinical relapse in patients with UC achieving different treatment targets.ResultsIn a meta-analysis of 17 studies that included 2608 patients with UC in clinical remission, compared to patients achieving MES 1, patients achieving MES 0 had a 52% lower risk of clinical relapse (relative risk, 0.48; 95% CI, 0.37-0.62). The median 12-month risk of clinical relapse in patients with MES 1 was 28.7%; the estimated annual risk of clinical relapse in patients with MES 0 was 13.7% (95% CI, 10.6-17.9). In a meta-analysis of 10 studies in patients in endoscopic remission (MES 0), patients who achieved histologic remission had a 63% lower risk of clinical relapse vs patients with persistent histologic activity (relative risk, 0.37; 95% CI, 0.24-0.56). Estimated annual risk of clinical relapse in who achieved achieving histologic remission was 5.0% (95% CI, 3.3-7.7).ConclusionsIn a systematic review and meta-analysis of patients with UC in clinical remission, we observed that patients achieving more rigorous treatment endpoints (endoscopic and histologic remission) have a substantially lower risk of clinical relapse compared with patients achieving clinical remission

Defective Induction of IL-27-Mediated Immunoregulation by Myeloid DCs in Multiple Sclerosis

The purpose of this study was to examine whether myeloid dendritic cells (mDCs) from patients with multiple sclerosis (MS) and healthy controls (HCs) become similarly tolerogenic when exposed to IL-27 as this may represent a potential mechanism of autoimmune dysregulation. Our study focused on natural mDCs that were isolated from HCs and MS patient peripheral blood mononuclear cells (PBMCs). After a 24-h treatment with IL-27 ± lipopolysaccharide (LPS), the mDCs were either harvested to identify IL-27-regulated gene expression or co-cultured with naive T-cells to measure how the treated DC affected T-cell proliferation and cytokine secretion. mDCs isolated from HCs but not untreated MS patients became functionally tolerogenic after IL-27 treatment. Although IL-27 induced both HC and untreated MS mDCs to produce similar amounts of IL-10, the tolerogenic HC mDCs expressed PD-L2, IDO1, and SOCS1, while the non-tolerogenic untreated MS mDCs expressed IDO1 and IL-6R. Cytokine and RNA analyses identified two signature blocks: the first identified genes associated with mDC tolerizing responses to IL-27, while the second was associated with the presence of MS. In contrast to mDCs from untreated MS patients, mDCs from HCs and IFNb-treated MS patients became tolerogenic in response to IL-27. The genes differentially expressed in the different donor IL-27-treated mDCs may contain targets that regulate mDC tolerogenic responses

Comparative Safety of Biologic Agents in Patients With Inflammatory Bowel Disease With Active or Recent Malignancy: A Multi-Center Cohort Study

Safety of biologic agents is a key consideration in patients with inflammatory bowel disease (IBD) and active or recent cancer. We compared the safety of tumor necrosis factor (TNF)-α antagonists vs non-TNF biologics in patients with IBD with active or recent cancer. We conducted a multicenter retrospective cohort study of patients with IBD and either active cancer (cohort A) or recent prior cancer (within ≤5 years; cohort B) who were treated with TNFα antagonists or non-TNF biologics after their cancer diagnosis. Primary outcomes were progression-free survival (cohort A) or recurrence-free survival (cohort B). Safety was compared using inverse probability of treatment weighting with propensity scores. In cohort A, of 125 patients (483.8 person-years of follow-up evaluation) with active cancer (age, 54 ± 15 y, 75% solid-organ malignancy), 10 of 55 (incidence rate [IR] per 100 py, 4.4) and 9 of 40 (IR, 10.4) patients treated with TNFα antagonists and non-TNF biologics had cancer progression, respectively. There was no difference in the risk of progression-free survival between TNFα antagonists vs non-TNF biologics (hazard ratio, 0.76; 95% CI, 0.25–2.30). In cohort B, of 170 patients (513 person-years of follow-up evaluation) with recent prior cancer (age, 53 ± 15 y, 84% solid-organ malignancy; duration of remission, 19 ± 19 mo), 8 of 78 (IR, 3.4) and 5 of 66 (IR 3.7) patients treated with TNFα antagonists and non-TNF biologics had cancer recurrence, respectively. The risk of recurrence-free survival was similar between both groups (hazard ratio, 0.94; 95% CI, 0.24–3.77). In patients with IBD with active or recent cancer, TNFα antagonists and non-TNF biologics have comparable safety. The choice of biologic should be dictated by IBD disease severity in collaboration with an oncologist