Synovial Tissue Heterogeneity in Rheumatoid Arthritis and Changes With Biologic and Targeted Synthetic Therapies to Inform Stratified Therapy.

The treatment of rheumatoid arthritis (RA) has been transformed with the introduction of biologic disease modifying anti-rheumatic drugs (bDMARD) and more recently, targeted synthetic DMARD (tsDMARD) therapies in the form of janus-kinase inhibitors. Nevertheless, response to these agents varies such that a trial and error approach is adopted; leading to poor patient quality of life, and long-term outcomes. There is thus an urgent need to identify effective biomarkers to guide treatment selection.

A Case of Adult-Onset Still's Disease Caused by a Novel Splicing Mutation in Successfully Treated With Tocilizumab.

encodes the NF-κB regulatory protein A20. High-penetrance heterozygous mutations in cause a haploinsufficiency of A20 (HA20), inadequate inhibition of NF-κB pathway, and an early onset autoinflammatory disorder. However, the clinical phenotype of patients with HA20 varies greatly and clinical diagnoses prior to establishing the genetic cause, included both autoimmune and autoinflammatory conditions.

TLR dependent XBP-1 activation induces an autocrine loop in rheumatoid arthritis synoviocytes.

X-box binding protein 1 (XBP1) is a central regulator of the endoplasmic reticulum (ER) stress response. It is induced via activation of the IRE1 stress sensor as part of the unfolded protein response (UPR) and has been implicated in several diseases processes. XBP1 can also be activated in direct response to Toll-like receptor (TLR) ligation independently of the UPR but the pathogenic significance of this mode of XBP1 activation is not well understood.

CTCF depletion alters chromatin structure and transcription of myeloid-specific factors.

Differentiation is a multistep process tightly regulated and controlled by complex transcription factor networks. Here, we show that the rate of differentiation of common myeloid precursor cells increases after depletion of CTCF, a protein emerging as a potential key factor regulating higher-order chromatin structure. We identified CTCF binding in the vicinity of important transcription factors regulating myeloid differentiation and showed that CTCF depletion impacts on the expression of these genes in concordance with the observed acceleration of the myeloid commitment.

A NF-κB-dependent dual promoter-enhancer initiates the lipopolysaccharide-mediated transcriptional activation of the chicken lysozyme in macrophages.

The transcriptional activation of the chicken lysozyme gene (cLys) by lipopolysaccharide (LPS) in macrophages is dependent on transcription of a LPS-Inducible Non-Coding RNA (LINoCR) triggering eviction of the CCCTC-binding factor (CTCF) from a negative regulatory element upstream of the lysozyme transcription start site. LINoCR is transcribed from a promoter originally characterized as a hormone response enhancer in the oviduct. Herein, we report the characterization of this cis-regulatory element (CRE).

Heterochromatin protein 1 gamma and IκB kinase alpha interdependence during tumour necrosis factor gene transcription elongation in activated macrophages.

IκB kinase α (IKKα) is part of the cytoplasmic IKK complex regulating nuclear factor-κB (NF-κB) release and translocation into the nucleus in response to pro-inflammatory signals. IKKα can also be recruited directly to the promoter of NF-κB-dependent genes by NF-κB where it phosphorylates histone H3 at serine 10, triggering recruitment of the bromodomain-containing protein 4 and the positive transcription elongation factor b. Herein, we report that IKKα travels with the elongating form of ribonucleic acid polymerase II together with heterochromatin protein 1 gamma (HP1γ) at NF-κB-dependent genes in activated macrophages.