Combining magnetically isolated CD45 cells with serum maintains intact drug responsiveness for ELISpot analysis in clinical trials.

Enzyme-linked immunosorbent spot analysis is frequently used to investigate immune responsiveness during clinical trials. However, ELISpot classically utilizes peripheral blood mononuclear cell isolates from whole blood, requiring relatively high blood draw volumes and removing both granulocytes and bound drug. Here, we describe a novel protocol whereby CD45 cells are magnetically isolated from human whole blood and co-incubated with serum isolated from the same subject.

Toll-like receptor 4 (TLR4) antagonists as potential therapeutics for intestinal inflammation.

Gastrointestinal inflammation is a hallmark of highly prevalent disorders, including cancer treatment-induced mucositis and ulcerative colitis. These disorders cause debilitating symptoms, have a significant impact on quality of life, and are poorly managed. The activation of toll-like receptor 4 (TLR4) has been proposed to have a major influence on the inflammatory signalling pathways of the intestinal tract.

Acute Colitis Drives Tolerance by Persistently Altering the Epithelial Barrier and Innate and Adaptive Immunity.

Background: Inflammatory bowel disease (IBD) has a remitting and relapsing disease course; however, relatively little is understood regarding how inflammatory damage in acute colitis influences the microbiota, epithelial barrier, and immune function in subsequent colitis.

Methods: Mice were administered trinitrobenzene sulphonic acid (TNBS) via enema, and inflammation was assessed 2 days (d2) or 28 days (d28) later. Colitis was reactivated in some mice by re-treating at 28 days with TNBS and assessing 2 days later (d30).

Effect of Fecal Microbiota Transplantation on 8-Week Remission in Patients With Ulcerative Colitis: A Randomized Clinical Trial.

Importance: High-intensity, aerobically prepared fecal microbiota transplantation (FMT) has demonstrated efficacy in treating active ulcerative colitis (UC). FMT protocols involving anaerobic stool processing methods may enhance microbial viability and allow efficacy with a lower treatment intensity.

Objective: To assess the efficacy of a short duration of FMT therapy to induce remission in UC using anaerobically prepared stool.

Immuno-PET of Innate Immune Markers CD11b and IL-1β Detects Inflammation in Murine Colitis.

Inflammatory bowel disease (IBD) is a chronic relapsing and remitting inflammatory disease of the gastrointestinal tract. The diagnosis and monitoring of IBD are reliant on endoscopy, which is invasive and does not provide information on specific mediators. Symptom flare in IBD is associated with increased activation of innate immune pathways.

Advances in Imaging Specific Mediators of Inflammatory Bowel Disease.

Inflammatory bowel disease (IBD) is characterized by chronic remitting and relapsing inflammation of the lower gastrointestinal tract. The etiology underlying IBD remains unknown, but it is thought to involve a hypersensitive immune response to environmental antigens, including the microbiota. Diagnosis and monitoring of IBD is heavily reliant on endoscopy, which is invasive and does not provide information regarding specific mediators.

Colonic migrating motor complexes are inhibited in acute tri-nitro benzene sulphonic acid colitis.

Background: Inflammatory Bowel Disease (IBD) is characterized by overt inflammation of the intestine and is typically accompanied by symptoms of bloody diarrhea, abdominal pain and cramping. The Colonic Migrating Motor Complex (CMMC) directs the movement of colonic luminal contents over long distances. The tri-nitrobenzene sulphonic acid (TNBS) model of colitis causes inflammatory damage to enteric nerves, however it remains to be determined whether these changes translate to functional outcomes in CMMC activity.

Co-expression of μ and δ opioid receptors by mouse colonic nociceptors.

Background And Purpose: To better understand opioid signalling in visceral nociceptors, we examined the expression and selective activation of μ and δ opioid receptors by dorsal root ganglia (DRG) neurons innervating the mouse colon.

Experimental Approach: DRG neurons projecting to the colon were identified by retrograde tracing. δ receptor-GFP reporter mice, in situ hybridization, single-cell RT-PCR and μ receptor-specific antibodies were used to characterize expression of μ and δ receptors.

Acute colitis chronically alters immune infiltration mechanisms and sensory neuro-immune interactions.

Objective: Little is understood regarding how disease progression alters immune and sensory nerve function in colitis. We investigated how acute colitis chronically alters immune recruitment and the impact this has on re-activated colitis. To understand the impact of disease progress on sensory systems we investigated the mechanisms underlying altered colonic neuro-immune interactions after acute colitis.

Fluoxetine for Maintenance of Remission and to Improve Quality of Life in Patients with Crohn's Disease: a Pilot Randomized Placebo-Controlled Trial.

Background And Aims: Previous studies have shown that antidepressants reduce inflammation in animal models of colitis. The present trial aimed to examine whether fluoxetine added to standard therapy for Crohn's disease [CD] maintained remission, improved quality of life [QoL] and/or mental health in people with CD as compared to placebo.

Methods: A parallel randomized double-blind placebo controlled trial was conducted.

Opioidergic effects on enteric and sensory nerves in the lower GI tract: basic mechanisms and clinical implications.

Opioids are one of the most prescribed drug classes for treating acute pain. However, chronic use is often associated with tolerance as well as debilitating side effects, including nausea and dependence, which are mediated by the central nervous system, as well as constipation emerging from effects on the enteric nervous system. These gastrointestinal (GI) side effects limit the usefulness of opioids in treating pain in many patients.

Immune derived opioidergic inhibition of viscerosensory afferents is decreased in Irritable Bowel Syndrome patients.

Alterations in the neuro-immune axis contribute toward viscerosensory nerve sensitivity and symptoms in Irritable Bowel Syndrome (IBS). Inhibitory factors secreted from immune cells inhibit colo-rectal afferents in health, and loss of this inhibition may lead to hypersensitivity and symptoms. We aimed to determine the immune cell type(s) responsible for opioid secretion in humans and whether this is altered in patients with IBS.

Deletion of interleukin-6 signal transducer gp130 in small sensory neurons attenuates mechanonociception and down-regulates TRPA1 expression.

Glycoprotein 130 (gp130) is the signal transducing receptor subunit for cytokines of the interleukin-6 (IL-6) family, and it is expressed in a multitude of cell types of the immune and nervous system. IL-6-like cytokines are not only key regulators of innate immunity and inflammation but are also essential factors for the differentiation and development of the somatosensory system. Mice with a null mutation of gp130 in primary nociceptive afferents (SNS-gp130(-/-)) are largely protected from hypersensitivity to mechanical stimuli in mouse models of pathological pain.

Linaclotide inhibits colonic nociceptors and relieves abdominal pain via guanylate cyclase-C and extracellular cyclic guanosine 3',5'-monophosphate.

Background & Aims: Linaclotide is a minimally absorbed agonist of guanylate cyclase-C (GUCY2C or GC-C) that reduces symptoms associated with irritable bowel syndrome with constipation (IBS-C). Little is known about the mechanism by which linaclotide reduces abdominal pain in patients with IBS-C.

Methods: We determined the effects of linaclotide on colonic sensory afferents in healthy mice and those with chronic visceral hypersensitivity.

Immune activation in irritable bowel syndrome: can neuroimmune interactions explain symptoms?

Irritable bowel syndrome (IBS) is a functional disorder of the gastrointestinal (GI) tract characterized by pain or discomfort from the lower abdominal region, which is associated with altered bowel habit. Despite its prevalence, there is currently a lack of effective treatment options for patients. IBS has long been considered as a neurological condition resulting from alterations in the brain gut axis, but immunological alterations are increasingly reported in IBS patients, consistent with the hypothesis that there is a chronic, but low-grade, immune activation.

Sensory neuro-immune interactions differ between irritable bowel syndrome subtypes.

Objective: The gut is a major site of contact between immune and sensory systems and evidence suggests that patients with irritable bowel syndrome (IBS) have immune dysfunction. Here we show how this dysfunction differs between major IBS subgroups and how immunocytes communicate with sensory nerves.

Design: Peripheral blood mononuclear cell supernatants from 20 diarrhoea predominant IBS (D-IBS) patients, 15 constipation predominant IBS (C-IBS) patients and 36 healthy subjects were applied to mouse colonic sensory nerves and effects on mechanosensitivity assessed.

Sprouting of colonic afferent central terminals and increased spinal mitogen-activated protein kinase expression in a mouse model of chronic visceral hypersensitivity.

Visceral pain following infection or inflammation is a major clinical problem. Although we have knowledge of how peripheral endings of colonic afferents change in disease, their central projections have been overlooked. With neuroanatomical tracing and colorectal distension (CRD), we sought to identify colonic afferent central terminals (CACTs), the dorsal horn (DH) neurons activated by colonic stimuli in the thoracolumbar (T10-L1) DH, and determine how they are altered by postinflammatory chronic colonic mechanical hypersensitivity.

TRPA1 contributes to specific mechanically activated currents and sensory neuron mechanical hypersensitivity.

The mechanosensory role of TRPA1 and its contribution to mechanical hypersensitivity in sensory neurons remains enigmatic. We elucidated this role by recording mechanically activated currents in conjunction with TRPA1 over- and under-expression and selective pharmacology. First, we established that TRPA1 transcript, protein and functional expression are more abundant in smaller-diameter neurons than larger-diameter neurons, allowing comparison of two different neuronal populations.

A novel role for TRPM8 in visceral afferent function.

Transient receptor potential ion channel melastatin subtype 8 (TRPM8) is activated by cold temperatures and cooling agents, such as menthol and icilin. Compounds containing peppermint are reported to reduce symptoms of bowel hypersensitivity; however, the underlying mechanisms of action are unclear. Here we determined the role of TRPM8 in colonic sensory pathways.

Identifying the Ion Channels Responsible for Signaling Gastro-Intestinal Based Pain.

We are normally unaware of the complex signalling events which continuously occur within our internal organs. Most of us only become cognisant when sensations of hunger, fullness, urgency or gas arise. However, for patients with organic and functional bowel disorders pain is an unpleasant and often debilitating reminder.