Project description:Ectopic lymphoid structures (ELS) can develop in rheumatoid arthritis (RA) synovial tissue, but the precise pathways of B cell activation and selection are not well understood. Here, we identified a unique B cell population in the synovium characterized by co-expression of a family of orphan nuclear receptors, NR4A1 (also known as NUR77), NR4A2 (NURR1) and NR4A3 (NOR1), that is highly enriched at both early and late stages of RA. See doi:10.1101/2021.05.14.443150 for details.
Project description:The study presents: - an optimized synovium dissociation protocol for single cell RNA-sequencing studies of the human synovium. The protocol enables the isolation of high yield of viable synovial cells from prospectively collected fresh synovial biopsies from patients with inflammatory arthritis with a minimal sample droupout. The protocol is derived from the method for dissociation of cryopreserved synovia published by Donlin and colleagues (Arthritis Res. Ther. 2019). - a reference single-cell atlas of fresh human synovium in inflammatory arthritis, comprising more than 100´000 unsorted synovial scRNA-seq profiles from 27 freshly dissociated synovia of patients with different types of inflammatory arthritis. The synovial cells segregate into ten lymphoid, 14 myeloid and 17 stromal synovial cell populations and subpopulations, including synovial neutrophils, representing broadly representing the cellular heterogeneity and composition of the human synovium in inflammatory arthritis.
Project description:We report the first comparative analysis between histology, RNA-seq of synovium and matched peripheral blood, and clinico-radiological parameters in early rheumatoid arthritis (RA). Using a novel modular approach, we describe underlying pathways associated with three pre-dominant RA pathotypes. Myeloid was associated with macrophages, lymphoid with B and plasma cells, and fibroid with minimal inflammatory cell infiltration. Synovium RNA-seq was better correlated with the pathotypes than blood RNA-seq, but peripheral blood signatures, including type I interferon, were detected as associated with particular myeloid or lymphoid pathotypes. This study describes the molecular heterogeneity of RA and provides major new insights into the cross compartmental molecular pathways that underlie RA.
Project description:Osteoarthritis (OA) causes pain and functional disability for over 500 million people worldwide and is characterized by progressive loss of cartilage and synovial hyperplasia from the articulating surfaces of diarthrodial joints. Although the etiology of the disease is unknown, it is widely accepted that these degenerative changes arise from an imbalance of synthetic and degradative pathways that control cartilage and synovium extracellular matrix metabolism. Genome-wide U133A Affymetrix oligonucleotide array set was used to comprehensively investigate the expression pattern in non-osteoarthritis (normal) and synovium obtained from OA and rheumatoid arthritis (RA) patients undergoing knee replacement surgery. This study was undertaken to understand the disease's molecular basis better and provide relevant insight into phenotypical alterations and mechanisms involved in OA pathogenesis.
Project description:Pseudotime analysis, cytotrace, velocity was used to determine the source of subpopulation. To compare the difference between PVNS and steady state synovium, we conduct collaborated analysis containing both PVNS and OA synovium. Qusage analysis reveal the difference of the subsets between them. We for the first time using single cell analysis delineating PVNS cell atlas and have deepen understanding toward PVNS Presumed function and source of certain subpopulation might be the future target that worth trying. We also locate major subpopulation that is responsible for its unremitting inflammation, angiogenesis and invasiveness.
Project description:Treatment refractory Rheumatoid Arthritis (RA) is a major clinical challenge. Drug-free remission is uncommon but provides proof-of-concept that articular immune-homeostasis can be reinstated. In this project, we used single-cell RNA- to study the role of synovial tissue macrophages in maintaining disease remission. We have sequenced synovial tissue macrophages from individuals with healthy synovium (as evaluated by MRI), patients with undifferentiated arthritis (UPA), RA patients naïve to treatment, RA patients resistant to treatment and RA patients in disease remission
Project description:At a given time, rheumatoid arthritis (RA) is a heterogeneous disease and its underlying molecular mechanisms is still poorly understood. Because previous microarrays studies have only focused on late RA stages, we aimed to compare the biological and molecular profiles in early and long-standing (LS) RA. Synovial biopsies obtained by arthroscopy were performed in 4 early untreated RA patients, 4 LS treated RA patients and 7 control patients. Extracted mRNA were linearly amplified and used for large-scale gene expression profiling by cDNA arrays. By gene ontology analysis, the different gene combinations obtained by comparison of early, LS RA and normal synovium were used to identify the biological processes, molecular functions and pathways involved at each stage. Three combinations of 719, 116 and 52 transcripts dissociated respectively early from LS RA patients, early or LS RA from normal synovium. We identified several gene clusters and distinct molecular signatures specifically related to early or LS RA suggesting the involvement of different pathological mechanisms at each stage. Early and LS RA have distinct molecular signatures with the participation of different biological processes during the course of the disease. These results suggest that a better knowledge of the main biological processes involved at a given RA stage might help the rheumatologist to choose the more appropriate treatment. PBMC then RNA were extracted from synovial biopsies of 4 eraly RA patients, 4 long-standing RA patients and from 7 normal synovium used as control. Each sample was hybridized three times in different nylon membrane.
Project description:We performed single-cell RNA-seq in order to characterize in high resolution the transcriptomic profiles, differentiation fates and heterogeneity of wild-type, HDAC3 or Dax1 knock-out cells in SL(RA) differentiation conditions.
Project description:Retinoic acid (RA), the main active vitamin A metabolite, controls multiple biological processes such as cell proliferation and differentiation through genomic programs and kinase cascades activation. Due to these properties, RA has proven anti-cancer capacity. Several breast cancer cells respond to the antiproliferative effects of RA, while others are RA-resistant. However, the overall signaling and transcriptional pathways that are altered in such cells have not been elucidated. Here, in a large-scale analysis of the phosphoproteins and in a genome-wide analysis of the RA-regulated genes, we compared two human breast cancer cell lines, a RA-responsive one, the MCF7 cell line, and a RA-resistant one, the BT474 cell line, which depicts several alterations of the "kinome".
Project description:Retinoic acid (RA), the main active vitamin A metabolite, controls multiple biological processes such as cell proliferation and differentiation through genomic programs and kinase cascades activation. Due to these properties, RA has proven anti-cancer capacity. Several breast cancer cells respond to the antiproliferative effects of RA, while others are RA-resistant. However, the overall signaling and transcriptional pathways that are altered in such cells have not been elucidated. Here, in a large-scale analysis of the phosphoproteins and in a genome-wide analysis of the RA-regulated genes, we compared two human breast cancer cell lines, a RA-responsive one, the MCF7 cell line, and a RA-resistant one, the BT474 cell line, which depicts several alterations of the "kinome".