Microbiota-dependent indole production stimulates the development of collagen-induced arthritis in mice.

Altered tryptophan catabolism has been identified in inflammatory diseases like rheumatoid arthritis (RA) and spondyloarthritis (SpA), but the causal mechanisms linking tryptophan metabolites to disease are unknown. Using the collagen-induced arthritis (CIA) model, we identified alterations in tryptophan metabolism, and specifically indole, that correlated with disease. We demonstrated that both bacteria and dietary tryptophan were required for disease and that indole supplementation was sufficient to induce disease in their absence.

Microbiota-dependent indole production is required for the development of collagen-induced arthritis.

Altered tryptophan catabolism has been identified in inflammatory diseases like rheumatoid arthritis (RA) and spondyloarthritis (SpA), but the causal mechanisms linking tryptophan metabolites to disease are unknown. Using the collagen-induced arthritis (CIA) model we identify alterations in tryptophan metabolism, and specifically indole, that correlate with disease. We demonstrate that both bacteria and dietary tryptophan are required for disease, and indole supplementation is sufficient to induce disease in their absence.

A Novel Approach toward Less Invasive Multiomics Gut Analyses: a Pilot Study.

Newer 'omics approaches, such as metatranscriptomics and metabolomics, allow functional assessments of the interaction(s) between the gut microbiome and the human host. However, in order to generate meaningful data with these approaches, the method of sample collection is critical. Prior studies have relied on expensive and invasive means toward sample acquisition, such as intestinal biopsy, while other studies have relied on easier methods of collection, such as fecal samples that do not necessarily represent those microbes in contact with the host.

Multi 'Omics Analysis of Intestinal Tissue in Ankylosing Spondylitis Identifies Alterations in the Tryptophan Metabolism Pathway.

Intestinal microbial dysbiosis, intestinal inflammation, and Th17 immunity are all linked to the pathophysiology of spondyloarthritis (SpA); however, the mechanisms linking them remain unknown. One potential hypothesis suggests that the dysbiotic gut microbiome as a whole produces metabolites that influence human immune cells. To identify potential disease-relevant, microbiome-produced metabolites, we performed metabolomics screening and shotgun metagenomics on paired colon biopsies and fecal samples, respectively, from subjects with axial SpA (axSpA, N=21), Crohn's disease (CD, N=27), and Crohn's-axSpA overlap (CD-axSpA, N=12), as well as controls (HC, N=24).

Barrier lymphocytes in spondyloarthritis.

Purpose Of Review: The clinical overlap between spondyloarthritis (SpA) and inflammation of barrier tissues such as the intestine and skin indicates a role of barrier tissue immunity in the development of SpA. Herein, we review the recent advances in understanding lymphocyte populations and functions within the intestine and skin implicated in the pathophysiology of SpA.

Recent Findings: A number of unique lymphocyte populations have been identified to be expanded within the gut and skin of patients with SpA, including γδ T cells, mucosa-associated invariant T (MAIT) cells, innate lymphoid cells (ILCs) and T resident memory (TRM) cells.

Molecular Biology Approaches to Understanding Spondyloarthritis.

New and emerging molecular techniques are expanding understanding of the pathophysiology of spondyloarthritis (SpA). Genome-wide association studies identified novel pathways in antigen processing and presentation as well as helper T cell type 17 (T17) immunity associated with SpA. Immune cell profiling techniques have supported T17 immune responses and increasingly are revealing intestinal mucosal immune cells as associated with disease.

Risk of Infections and Cancer in Patients With Rheumatologic Diseases Receiving Interleukin Inhibitors: A Systematic Review and Meta-analysis.

Importance: The safety profile of interleukin (IL) inhibitors is not well established.

Objective: To assess the risk of serious infections, opportunistic infections, and cancer in patients with rheumatologic diseases treated with IL inhibitors.

Data Sources: Ovid MEDLINE and Epub Ahead of Print, In-Process & Other Non-Indexed Citations; Ovid MEDLINE Daily; Ovid Embase; Ovid Cochrane Central Register of Controlled Trials; Ovid Cochrane Database of Systematic Reviews; and Scopus were searched (inception to November 30, 2018).

The Influence of Depression on Health Care Expenditures Among Adults with Spondylosis, Intervertebral Disc Disorders, and Other Back Problems in the United States.

Background: Back pain is a very prevalent complaint, affecting two-thirds of the US population, and it accounts for $100 billion annually in health care expenditures. The occurrence of depression has been reported in existing literature among patients with back pain, but there is limited information regarding health care expenditures among patients with back pain and concurrent depression.

Objective: To assess excess total and subtypes of health care expenditures among adults with spondylosis, intervertebral disc disorders, and other back problems who reported having depression compared with those without depression in the United States.

The 100 top-cited publications in psoriatic arthritis: a bibliometric analysis.

Background: Citation analysis is a quantitative, bibliometric method that analyzes the frequency and pattern of citations in any given scientific discipline. Over the last two decades, the study of psoriatic arthritis has undergone substantial progress, which has enhanced our ability to assess and treat the disease, and yet an updated citation analysis that reflects these advances is lacking.

Objective: To highlight the scientific progress in psoriatic arthritis by identifying and analyzing the 100 top-cited psoriatic arthritis articles from the last 40 years.

A systematic review and meta-analysis of the efficacy and safety of the interleukin (IL)-12/23 and IL-17 inhibitors ustekinumab, secukinumab, ixekizumab, brodalumab, guselkumab and tildrakizumab for the treatment of moderate to severe plaque psoriasis.

Objective: To systematically analyze the efficacy and safety of interleukin (IL)-12/23, IL-17, and selective IL-23 inhibitors in moderate to severe plaque psoriasis.

Methods And Results: Twenty-four randomized placebo-controlled trials were included. Compared to placebo, risk ratios (RR) of achieving PASI-75 and PGA/IGA 0/1 respectively were 20.

Targeting the NF-κB Pathway as a Combination Therapy for Advanced Thyroid Cancer.

NF-κB signaling plays an important role in tumor cell proliferation, cell survival, angiogenesis, invasion, metastasis and drug/radiation resistance. Combination therapy involving NF-κB pathway inhibition is an attractive strategy for the treatment of advanced forms of thyroid cancer. This study was designed to test the efficacy of NF-κB pathway inhibition in combination with cytotoxic chemotherapy, using docetaxel and ionizing radiation in in vitro models of thyroid cancer.

OS-FRET: a new one-sample method for improved FRET measurements.

Fluorescence resonance energy transfer (FRET) is a powerful tool for studying macromolecular assemblies in vitro under near-physiological conditions. Here we present a new type of one-sample FRET (OS-FRET) method employing a novel, nonfluorescent methanethiosulfonate-linked acceptor that can be reversibly coupled to a target sulfhydryl residue via a disulfide bond. After the quenched donor emission is quantitated, the acceptor is removed by reduction, allowing measurement of unquenched donor emission in the same sample.