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result(s) for
"Darren Tabechian"
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Divergent Gene Activation in Peripheral Blood and Tissues of Patients with Rheumatoid Arthritis, Psoriatic Arthritis and Psoriasis following Infliximab Therapy
2014
The immune inflammatory disorders rheumatoid arthritis (RA), psoriatic arthritis (PsA) and psoriasis (Ps) share common pathologic features and show responsiveness to anti-tumor necrosis factor (TNF) agents yet they are phenotypically distinct. The aim of this study was to examine if anti-TNF therapy is associated with divergent gene expression profiles in circulating cells and target tissues of patients with these diseases.
Peripheral blood CD14+ and CD14- cells were isolated from 9 RA, 12 PsA and 10 Ps patients before and after infliximab (IFX) treatment. Paired synovial (n=3, RA, PsA) and skin biopsies (n=5, Ps) were also collected. Gene expression was analyzed by microarrays.
26 out of 31 subjects responded to IFX. The transcriptional response of CD14+ cells to IFX was unique for the three diseases, with little overlap (<25%) in significantly changed gene lists (with PsA having the largest number of changed genes). In Ps, altered gene expression was more pronounced in lesional skin (relative to paired, healthy skin) compared to blood (relative to healthy controls). Marked suppression of up-regulated genes in affected skin was noted 2 weeks after therapy but the expression patterns differed from uninvolved skin. Divergent patterns of expression were noted between the blood cells and skin or synovial tissues in individual patients. Functions that promote cell differentiation, proliferation and apoptosis in all three diseases were enriched. RA was enriched in functions in CD14- cells, PsA in CD14+ cells and Ps in both CD14+ and CD14- cells, however, the specific functions showed little overlap in the 3 disorders.
Divergent patterns of altered gene expression are observed in RA, PsA and Ps patients in blood cells and target organs in IFX responders. Differential gene expression profiles in the blood do not correlate with those in target organs.
Journal Article
Precision Medicine in Rheumatology: The Promise of Ultrasound-Guided Synovial Biopsy, Barriers to Its Implementation in the United States, and Proposed Solutions
by
Mandelin, Arthur M.
,
Ben-Artzi, Ami
,
Horowitz, Diane Lewis
in
Arthritis, Rheumatoid - diagnostic imaging
,
Humans
,
Image-Guided Biopsy - methods
2024
Purpose of Review
In the clinical evaluation of inflammatory arthritis and the research into its pathogenesis, there is a growing role for the direct analysis of synovial tissue. Over the years, various biopsy techniques have been used to obtain human synovial tissue samples, and there have been progressive improvements in the safety, tolerability, and utility of the procedure.
Recent Findings
The latest advancement in synovial tissue biopsy techniques is the use of ultrasound imaging to guide the biopsy device, along with evolution in the characteristics of the device itself. While ultrasound guided synovial biopsy (UGSB) has taken a strong foothold in Europe, the procedure is still relatively new to the United States of America (USA).
Summary
In this paper, we describe the expansion of UGSB in the USA, elucidate the challenges faced by rheumatologists developing UGSB programs in the USA, and describe several strategies for overcoming these challenges.
Journal Article
Analysis of human factor H-related gene and protein expressed in rheumatoid arthritis synovium identifies a novel mechanism promoting dysregulated complement pathway activation
2025
Factor H (FH) is a negative regulator of the alternative pathway (AP) of complement however, five human factor H-related (FHR) proteins, can also function ex vivo as positive regulators. We compare bulk FH and FHR mRNA expressions in both the human rheumatoid arthritis (RA) synovium and blood cells from the Pathobiology of Early Arthritis Cohort (PEAC) and the Stratification of biological therapies for Rheumatoid Arthritis by Pathobiology (STRAP) Cohort. FH and FHR proteins were detected using multiplexed immunohistochemistry (MIHC) in synovium. In three pathotypes, in the synovium, no differences were found in the expression of FHR mRNA. In the synovium, a significant negative correlation was observed between FH expression and the disease activity score and X-ray joint space narrowing. In RA patients, there was a significant positive correlation between FHR3 mRNA level, anti-cyclic citrullinated peptide (CCP) antibodies and rheumatoid factor (RF). FHR proteins were co-localized in the synovial lining area along with complement C3 while FH was almost undetectable in the synovial lining but abundant in sub-synovial lining areas. We do not know whether FH and FHR proteins are locally generated and deposited in synovium or come from circulation. In sum, due to the absence of FH but the presence of FHRs, the synovial lining might fail to be protected from complement-mediated attack, and FHR3 may play a particularly important pathogenic role.
Journal Article
Divergent Gene Activation in Peripheral Blood and Tissues of Patients with Rheumatoid Arthritis, Psoriatic Arthritis and Psoriasis following Infliximab Therapy: e110657
2014
Objective The immune inflammatory disorders rheumatoid arthritis (RA), psoriatic arthritis (PsA) and psoriasis (Ps) share common pathologic features and show responsiveness to anti-tumor necrosis factor (TNF) agents yet they are phenotypically distinct. The aim of this study was to examine if anti-TNF therapy is associated with divergent gene expression profiles in circulating cells and target tissues of patients with these diseases. Methods Peripheral blood CD14+ and CD14- cells were isolated from 9 RA, 12 PsA and 10 Ps patients before and after infliximab (IFX) treatment. Paired synovial (n = 3, RA, PsA) and skin biopsies (n = 5, Ps) were also collected. Gene expression was analyzed by microarrays. Results 26 out of 31 subjects responded to IFX. The transcriptional response of CD14+ cells to IFX was unique for the three diseases, with little overlap (<25%) in significantly changed gene lists (with PsA having the largest number of changed genes). In Ps, altered gene expression was more pronounced in lesional skin (relative to paired, healthy skin) compared to blood (relative to healthy controls). Marked suppression of up-regulated genes in affected skin was noted 2 weeks after therapy but the expression patterns differed from uninvolved skin. Divergent patterns of expression were noted between the blood cells and skin or synovial tissues in individual patients. Functions that promote cell differentiation, proliferation and apoptosis in all three diseases were enriched. RA was enriched in functions in CD14- cells, PsA in CD14+ cells and Ps in both CD14+ and CD14- cells, however, the specific functions showed little overlap in the 3 disorders. Conclusion Divergent patterns of altered gene expression are observed in RA, PsA and Ps patients in blood cells and target organs in IFX responders. Differential gene expression profiles in the blood do not correlate with those in target organs.
Journal Article
Clonal associations of lymphocyte subsets and functional states revealed by single cell antigen receptor profiling of T and B cells in rheumatoid arthritis synovium
2023
Rheumatoid arthritis (RA) is an autoimmune disease initiated by antigen-specific T cells and B cells, which promote synovial inflammation through a complex set of interactions with innate immune and stromal cells. To better understand the phenotypes and clonal relationships of synovial T and B cells, we performed single-cell RNA and repertoire sequencing on paired synovial tissue and peripheral blood samples from 12 donors with seropositive RA ranging from early to chronic disease. Paired transcriptomic-repertoire analyses highlighted 3 clonally distinct CD4 T cells populations that were enriched in RA synovium: T peripheral helper (Tph) and T follicular helper (Tfh) cells, CCL5+ T cells, and T regulatory cells (Tregs). Among these cells, Tph cells showed a unique transcriptomic signature of recent T cell receptor (TCR) activation, and clonally expanded Tph cells expressed an elevated transcriptomic effector signature compared to non-expanded Tph cells. CD8 T cells showed higher oligoclonality than CD4 T cells, and the largest CD8 T cell clones in synovium were highly enriched in
+ cells. TCR analyses revealed CD8 T cells with likely viral-reactive TCRs distributed across transcriptomic clusters and definitively identified MAIT cells in synovium, which showed transcriptomic features of TCR activation. Among B cells, non-naive B cells including age-associated B cells (ABC),
activated B cells, and plasma cells, were enriched in synovium and had higher somatic hypermutation rates compared to blood B cells. Synovial B cells demonstrated substantial clonal expansion, with ABC, memory, and activated B cells clonally linked to synovial plasma cells. Together, these results reveal clonal relationships between functionally distinct lymphocyte populations that infiltrate RA synovium.
Journal Article
Deep immunophenotyping reveals circulating activated lymphocytes in individuals at risk for rheumatoid arthritis
2023
Rheumatoid arthritis (RA) is a systemic autoimmune disease with currently no universally highly effective prevention strategies. Identifying pathogenic immune phenotypes in 'At-Risk' populations prior to clinical disease onset is crucial to establishing effective prevention strategies. Here, we applied mass cytometry to deeply characterize the immunophenotypes in blood from At-Risk individuals identified through the presence of serum antibodies to citrullinated protein antigens (ACPA) and/or first-degree relative (FDR) status (n=52), as compared to established RA (n=67), and healthy controls (n=48). We identified significant cell expansions in At-Risk individuals compared with controls, including CCR2+CD4+ T cells, T peripheral helper (Tph) cells, type 1 T helper cells, and CXCR5+CD8+ T cells. We also found that CD15+ classical monocytes were specifically expanded in ACPA-negative FDRs, and an activated PAX5
naïve B cell population was expanded in ACPA-positive FDRs. Further, we developed an \"RA immunophenotype score\" classification method based on the degree of enrichment of cell states relevant to established RA patients. This score significantly distinguished At-Risk individuals from controls. In all, we systematically identified activated lymphocyte phenotypes in At-Risk individuals, along with immunophenotypic differences among both ACPA+ and ACPA-FDR At-Risk subpopulations. Our classification model provides a promising approach for understanding RA pathogenesis with the goal to further improve prevention strategies and identify novel therapeutic targets.
Journal Article
Defining Inflammatory Cell States in Rheumatoid Arthritis Joint Synovial Tissues by Integrating Single-cell Transcriptomics and Mass Cytometry
by
Kelly, Stephen
,
Gregersen, Peter K
,
Lederer, James A
in
CD11c antigen
,
CD8 antigen
,
Computer applications
2018
To define the cell populations in rheumatoid arthritis (RA) driving joint inflammation, we applied single-cell RNA-seq (scRNA-seq), mass cytometry, bulk RNA-seq, and flow cytometry to sorted T cells, B cells, monocytes, and fibroblasts from 51 synovial tissue RA and osteoarthritis (OA) patient samples. Utilizing an integrated computational strategy based on canonical correlation analysis to 5,452 scRNA-seq profiles, we identified 18 unique cell populations. Combining mass cytometry and transcriptomics together revealed cell states expanded in RA synovia: THY1+HLAhigh sublining fibroblasts (OR=33.8), IL1B+ pro-inflammatory monocytes (OR=7.8), CD11c+T-bet+ autoimmune-associated B cells (OR=5.7), and PD-1+ Tph/Tfh (OR=3.0). We also defined CD8+ T cell subsets characterized by GZMK+, GZMB+, and GNLY+ expression. Using bulk and single-cell data, we mapped inflammatory mediators to source cell populations, for example attributing IL6 production to THY1+HLAhigh fibroblasts and naive B cells, and ILB to pro-inflammatory monocytes. These populations are potentially key mediators of RA pathogenesis.