Mediators of Filgotinib Treatment Effects in Ulcerative Colitis: Exploring Circulating Biomarkers in the Phase 2b/3 SELECTION Study.

Background: We utilized patient samples from the large, phase 2b/3 SELECTION trial to identify circulating biomarkers of ulcerative colitis (UC) and potential early mediators of filgotinib treatment effects.

Methods: Samples were collected at baseline and during the induction phase of the SELECTION trial. Evaluated biomarkers comprised serum and stool proteins (measured by enzyme-linked immunosorbent assay), whole-blood cell counts, and whole-blood RNA-seq-derived gene-expression factors identified via exploratory factor analysis.

A Phase 2, Randomized, Placebo-Controlled Study Evaluating Matrix Metalloproteinase-9 Inhibitor, Andecaliximab, in Patients With Moderately to Severely Active Crohn's Disease.

Background And Aims: Matrix metalloproteinase-9 [MMP9] is implicated in the pathogenesis of Crohn's disease and may serve as a potential biomarker. A phase 2 trial was conducted to examine the efficacy and safety of the anti-MMP9 antibody andecaliximab [GS-5745] in patients with moderately to severely active Crohn's disease.

Methods: Patients were randomized 1:2:2:2 to receive subcutaneous injections of placebo weekly [QW], andecaliximab 150 mg every 2 weeks [Q2W], andecaliximab 150 mg QW, or andecaliximab 300 mg QW.

Andecaliximab [Anti-matrix Metalloproteinase-9] Induction Therapy for Ulcerative Colitis: A Randomised, Double-Blind, Placebo-Controlled, Phase 2/3 Study in Patients With Moderate to Severe Disease.

Background And Aims: Matrix metalloproteinase-9 [MMP9] is implicated in the pathogenesis of ulcerative colitis [UC] via disruption of intestinal barrier integrity and function. A phase 2/3 combined trial was designed to examine the efficacy, safety, and pharmacokinetics of the anti-MMP9 antibody, andecaliximab [formerly GS-5745], in patients with moderately to severely active UC.

Methods: Patients were randomised [1:1:1] to receive placebo, 150 mg andecaliximab every 2 weeks [Q2W], or 150 mg andecaliximab weekly [QW], via subcutaneous administration.

Circulating and Tissue-Resident CD4 T Cells With Reactivity to Intestinal Microbiota Are Abundant in Healthy Individuals and Function Is Altered During Inflammation.

Background & Aims: Interactions between commensal microbes and the immune system are tightly regulated and maintain intestinal homeostasis, but little is known about these interactions in humans. We investigated responses of human CD4 T cells to the intestinal microbiota. We measured the abundance of T cells in circulation and intestinal tissues that respond to intestinal microbes and determined their clonal diversity.

Beyond Histological Remission: Intramucosal Calprotectin as a Potential Predictor of Outcomes in Ulcerative Colitis.

Background And Aims: Histological remission and low faecal calprotectin are positive prognostic factors in ulcerative colitis [UC]. Intramucosal calprotectin [iMC], which can be readily determined by immunohistochemistry, has not so far been evaluated as a predictor of outcome in UC. We aimed to investigate the relationship between iMC and clinical, endoscopic, and histological measures of remission in UC, and the independent prognostic value of iMC.

Glucocorticoids Suppress CCR9-Mediated Chemotaxis, Calcium Flux, and Adhesion to MAdCAM-1 in Human T Cells.

CCR9 expressed on T lymphocytes mediates migration to the small intestine in response to a gradient of CCL25. CCL25-stimulated activation of α4β7 integrin promotes cell adherence to mucosal addressin cell adhesion molecule-1 (MAdCAM-1) expressed by vascular endothelial cells of the intestine, further mediating gut-specific homing. Inflammatory bowel disease is a chronic inflammatory condition that primarily affects the gastrointestinal tract and is characterized by leukocyte infiltration.

CCR9 antagonism: potential in the treatment of Inflammatory Bowel Disease.

Inflammatory Bowel Disease (IBD), mainly comprising Crohn's disease (CD) and ulcerative colitis (UC), is a chronic condition that primarily affects the intestine and is characterized by leukocytic infiltration. Blocking the migration of leukocytes from the circulation is therefore a reasonable therapeutic goal. Recent clinical trials using this approach have shown promise, with the monoclonal antibody to α4β7 integrin, vedolizumab, and previously with the monoclonal antibody to the α4 subunit, natalizumab.

Ratiometric analysis of fura red by flow cytometry: a technique for monitoring intracellular calcium flux in primary cell subsets.

Calcium flux is a rapid and sensitive measure of cell activation whose utility could be enhanced with better techniques for data extraction. We describe a technique to monitor calcium flux by flow cytometry, measuring Fura Red calcium dye by ratiometric analysis. This technique has several advantages: 1) using a single calcium dye provides an additional channel for surface marker characterization, 2) allows robust detection of calcium flux by minority cell populations within a heterogeneous population of primary T cells and monocytes 3) can measure total calcium flux and additionally, the proportion of responding cells, 4) can be applied to studying the effects of drug treatment, simultaneously stimulating and monitoring untreated and drug treated cells.

Characterization of CCX282-B, an orally bioavailable antagonist of the CCR9 chemokine receptor, for treatment of inflammatory bowel disease.

The chemokine system represents a diverse group of G protein-coupled receptors responsible for orchestrating cell recruitment under both homeostatic and inflammatory conditions. Chemokine receptor 9 (CCR9) is a chemokine receptor known to be central for migration of immune cells into the intestine. Its only ligand, CCL25, is expressed at the mucosal surface of the intestine and is known to be elevated in intestinal inflammation.

Engineering attenuated virus vaccines by controlling replication fidelity.

Long-lasting protection against viral infection is best achieved by vaccination with attenuated viruses. Obtaining stably attenuated vaccine strains has traditionally been an empirical process, which greatly restricts the number of effective vaccines for viral diseases. Here we describe a rational approach for engineering stably attenuated viruses that can serve as safe and effective vaccines.