Transcription Factor NFAT5 Promotes Migration and Invasion of Rheumatoid Synoviocytes via Coagulation Factor III and CCL2

Lee, Saseong,Kong, Jin-Sun,You, Sungyong,Kwon, H. Moo,Yoo, Seung-Ah,Cho, Chul-Soo,Kim, Wan-Uk The American Association of Immunologists, Inc. 2018 JOURNAL OF IMMUNOLOGY Vol.201 No.2

<P>Fibroblast-like synoviocytes (FLSs) play a key role in the progression of rheumatoid arthritis (RA) as a primary component of invasive hypertrophied pannus. FLSs of RA patients (RA-FLSs) exhibit cancer-like features, including promigratory and proinvasive activities that largely contribute to joint cartilage and bone destruction. In this study, we hypothesized that the NF of activated T cell 5 (NFAT5), a transcription factor involving tumor invasiveness, would control the migration and invasion of RA-FLSs. Analyses of transcriptomes demonstrated the significant involvement of NFAT5 in locomotion of RA-FLSs and that tissue factor (TF; also known as coagulation factor III) and CCL2 were the major downstream target genes of NFAT5 involving FLS migration and invasion. In cultured RA-FLSs, IL-1β and TGF-β increased TF and CCL2 expression by upregulating NFAT5 expression via p38 MAPK. Functional assays demonstrated that NFAT5- or TF-deficient RA-FLSs displayed decreased lamellipodia formation, cell migration, and invasion under IL-1β– or TGF-β–stimulated conditions. Conversely, factor VIIa, a specific activator of TF, increased migration of RA-FLSs, which was blocked by NFAT5 knockdown. Recombinant CCL2 partially restored the decrease in migration and invasion of NFAT5-deficient RA-FLSs stimulated with IL-1β. NFAT5-knockout mouse FLSs also showed decreased expressions of TF and CCL2 and reduced cell migration. Moreover, KRN2, a specific inhibitor of NFAT5, suppressed migration of FLSs stimulated with TGF-β. Conclusively, to our knowledge, this is the first study to provide evidence of a functional link between osmoprotective NFAT5 and TF in the migration and invasion of RA-FLSs and supports a role for NFAT5 blockade in the treatment of RA.</P>

Applications of systems approaches in the study of rheumatic diseases

Kim, Ki-Jo,Lee, Saseong,Kim, Wan-Uk The Korean Association of Internal Medicine 2015 The Korean Journal of Internal Medicine Vol.30 No.2

<P>The complex interaction of molecules within a biological system constitutes a functional module. These modules are then acted upon by both internal and external factors, such as genetic and environmental stresses, which under certain conditions can manifest as complex disease phenotypes. Recent advances in high-throughput biological analyses, in combination with improved computational methods for data enrichment, functional annotation, and network visualization, have enabled a much deeper understanding of the mechanisms underlying important biological processes by identifying functional modules that are temporally and spatially perturbed in the context of disease development. Systems biology approaches such as these have produced compelling observations that would be impossible to replicate using classical methodologies, with greater insights expected as both the technology and methods improve in the coming years. Here, we examine the use of systems biology and network analysis in the study of a wide range of rheumatic diseases to better understand the underlying molecular and clinical features.</P>

Leukocyte-specific protein 1 regulates T-cell migration in rheumatoid arthritis

Hwang, Seong-Hye,Jung, Seung-Hyun,Lee, Saseong,Choi, Susanna,Yoo, Seung-Ah,Park, Ji-Hwan,Hwang, Daehee,Shim, Seung Cheol,Sabbagh, Laurent,Kim, Ki-Jo,Park, Sung Hwan,Cho, Chul-Soo,Kim, Bong-Sung,Leng, National Academy of Sciences 2015 PROCEEDINGS OF THE NATIONAL ACADEMY OF SCIENCES OF Vol.112 No.47

<P><B>Significance</B></P><P>We screened rheumatoid arthritis (RA)-associated copy number variations (CNVs) across the whole genome and identified significant deletion variants encompassing leukocyte-specific protein 1 (LSP1) gene. Functional assays revealed that LSP1, induced by T-cell receptor activation, negatively regulates T-cell migration. Loss of <I>Lsp1</I> promotes T-cell migration into antigen-instilled tissues and draining lymph nodes in mice with T-cell–dependent chronic inflammation. Moreover, patients with RA show diminished expression of LSP1 in peripheral T cells with increased migratory capacity. To our knowledge, our work is the first to demonstrate how CNVs result in immune dysfunction and a disease phenotype, highlighting the importance of <I>LSP1</I> CNVs and LSP1 insufficiency in the pathogenesis of RA.</P><P>Copy number variations (CNVs) have been implicated in human diseases. However, it remains unclear how they affect immune dysfunction and autoimmune diseases, including rheumatoid arthritis (RA). Here, we identified a novel leukocyte-specific protein 1 (<I>LSP1</I>) deletion variant for RA susceptibility located in 11p15.5. We replicated that the copy number of LSP1 gene is significantly lower in patients with RA, which correlates positively with LSP1 protein expression levels. Differentially expressed genes in <I>Lsp1-</I>deficient primary T cells represent cell motility and immune and cytokine responses. Functional assays demonstrated that LSP1, induced by T-cell receptor activation, negatively regulates T-cell migration by reducing ERK activation in vitro. In mice with T-cell–dependent chronic inflammation, loss of <I>Lsp1</I> promotes migration of T cells into the target tissues as well as draining lymph nodes, exacerbating disease severity. Moreover, patients with RA show diminished expression of LSP1 in peripheral T cells with increased migratory capacity, suggesting that the defect in LSP1 signaling lowers the threshold for T-cell activation. To our knowledge, our work is the first to demonstrate how CNVs result in immune dysfunction and a disease phenotype. Particularly, our data highlight the importance of <I>LSP1</I> CNVs and LSP1 insufficiency in the pathogenesis of RA and provide previously unidentified insights into the mechanisms underlying T-cell migration toward the inflamed synovium in RA.</P>

Continuous monitoring of arthritis in animal models using optical imaging modalities

Son, Taeyoon,Yoon, Hyung-Ju,Lee, Saseong,Jang, Won Seuk,Jung, Byungjo,Kim, Wan-Uk SPIE - International Society for Optical Engineeri 2014 JOURNAL OF BIOMEDICAL OPTICS Vol.19 No.10

<P>Given the several difficulties associated with histology, including difficulty in continuous monitoring, this study aimed to investigate the feasibility of optical imaging modalities?cross-polarization color (CPC) imaging, erythema index (EI) imaging, and laser speckle contrast (LSC) imaging?for continuous evaluation and monitoring of arthritis in animal models. C57BL/6 mice, used for the evaluation of arthritis, were divided into three groups: arthritic mice group (AMG), positive control mice group (PCMG), and negative control mice group (NCMG). Complete Freunds adjuvant, mineral oil, and saline were injected into the footpad for AMG, PCMG, and NCMG, respectively. LSC and CPC images were acquired from 0 through 144 h after injection for all groups. EI images were calculated from CPC images. Variations in feet area, EI, and speckle index for each mice group over time were calculated for quantitative evaluation of arthritis. Histological examinations were performed, and the results were found to be consistent with those from optical imaging analysis. Thus, optical imaging modalities may be successfully applied for continuous evaluation and monitoring of arthritis in animal models.</P>

Transcriptional Regulator CTR9 Inhibits Th17 Differentiation via Repression of IL-17 Expression

Yoo, Hyeon-Seok,Choi, Yongwook,Ahn, Narae,Lee, Saseong,Kim, Wan-Uk,Jang, Min Seong,Jang, Myoung Ho,Kim, Yon Su,Yoo, Joo-Yeon The American Association of Immunologists, Inc. 2014 JOURNAL OF IMMUNOLOGY Vol.192 No.4

<P>PAF complex is an evolutionarily conserved transcriptional complex that associates with RNA polymerase II in the coding region of actively transcribing genes. Although its transcriptional activity is closely related to diverse cellular processes, such as cell-cycle progression or development in mammals, its role in immune responses has not been addressed yet. In this study, we show that CTR9, a component of PAF complex, functions as a repressor of Th17 differentiation. Both mRNA and protein levels of CTR9 were significantly decreased during the differentiation processes of naive T into Th17 effector cells. When CTR9 was depleted, IL-17 expression was induced and differentiation into Th17 cells enhanced. In naive T cells, CTR9 occupied the coding region of <I>Il17a</I>, but dissociated under Th17 in vitro-polarizing conditions. In contrast, both CDC73 and PAF1 were recruited to the <I>Il17a</I> locus under Th17-differentiation conditions. In the IL-6–stimulated splenocytes, expression of CTR9 was decreased, and chromatin-bound CTR9 disappeared in the coding region of <I>Il17a</I>. IL-6 also directly repressed expression of CTR9 gene, as promoter activity of CTR9 was similarly repressed by IL-6 treatment. Moreover, in mice with collagen-induced arthritis, lentivirus-mediated CTR9 overexpression in the joints ameliorated arthritis severity, decreasing the frequency of CD4<SUP>+</SUP>IL-17<SUP>+</SUP> T cells in lymph nodes. In conclusion, our data propose a novel feed-forward loop of IL-17 transcriptional regulatory circuit, via IL-6–mediated repression of CTR9 which is a transcriptional repressor of IL-17.</P>

Distinct Urinary Metabolic Profile in Rheumatoid Arthritis Patients: A Possible Link between Diet and Arthritis Phenotype

( Jung Hee Koh ),( Yune-jung Park ),( Saseong Lee ),( Young-shick Hong ),( Kwan Soo Hong ),( Seung-ah Yoo ),( Chul-soo Cho ),( Wan-uk Kim ) 대한류마티스학회 2019 대한류마티스학회지 Vol.26 No.1

Objective. We undertook this study to investigate the discriminant metabolites in urine from patients with established rheumatoid arthritis (RA), systemic lupus erythematosus (SLE), and from healthy individuals. Methods. Urine samples were collected from 148 RA patients, 41 SLE patients and 104 healthy participants. The urinary metabolomic profiles were assessed using ¹H nuclear magnetic resonance spectroscopy. The relationships between discriminant metabolites and clinical variables were assessed. Collagen-induced arthritis was induced in mice to determine if a choline-rich diet reduces arthritis progression. Results. The urinary metabolic fingerprint of patients with established RA differs from that of healthy controls and SLE patients. Markers of altered gut microbiota (trimethylamine-N-oxide, TMAO), and oxidative stress (dimethylamine) were upregulated in patients with RA. In contrast, markers of mitochondrial dysfunction (citrate and succinate) and metabolic waste products (p-cresol sulfate, p-CS) were downregulated in patients with RA. TMAO and dimethylamine were negatively associated with serum inflammatory markers in RA patients. In particular, patients with lower p-CS levels exhibited a more rapid radiographic progression over two years than did those with higher p-CS levels. The in vivo functional study demonstrated that mice fed with 1% choline, a source of TMAO experienced a less severe form of collagen-induced arthritis than did those fed a control diet. Conclusion. Patients with RA showed a distinct urinary metabolomics pattern. Urinary metabolites can reflect a pattern indicative of inflammation and accelerated radiographic progression of RA. A choline-rich diet reduces experimentally-induced arthritis. This finding suggests that the interaction between diet and the intestinal microbiota contributes to the RA phenotype. (J Rheum Dis 2019;26:46-56)

Placental Growth Factor-1 and -2 Induce Hyperplasia and Invasiveness of Primary Rheumatoid Synoviocytes

Yoo, Seung-Ah,Park, Ji-Hwan,Hwang, Seong-Hye,Oh, Sang-Min,Lee, Saseong,Cicatiello, Valeria,Rho, Sangchul,De Falco, Sandro,Hwang, Daehee,Cho, Chul-Soo,Kim, Wan-Uk The American Association of Immunologists, Inc. 2015 JOURNAL OF IMMUNOLOGY Vol.194 No.6

<P>Inflammation-mediated oncogenesis has been implicated in a variety of cancer types. Rheumatoid synovial tissues can be viewed as a tumor-like mass, consisting of hyperplastic fibroblast-like synoviocytes (FLSs). FLSs of rheumatoid arthritis (RA) patients have promigratory and invasive characteristics, which may be caused by chronic exposure to genotoxic stimuli, including hypoxia and growth factors. We tested whether a transformed phenotype of RA-FLSs is associated with placental growth factor (PlGF), a representative angiogenic growth factor induced by hypoxia. In this study, we identified <I>PlGF-1</I> and <I>PlGF-2</I> as the major <I>PlGF</I> isoforms in RA-FLSs. Global gene expression profiling revealed that cell proliferation, apoptosis, angiogenesis, and cell migration were mainly represented by differentially expressed genes in RA-FLSs transfected with small interfering RNA for <I>PlGF</I>. Indeed, <I>PlGF</I>-deficient RA-FLSs showed a decrease in cell proliferation, migration, and invasion, but an increase in apoptotic death in vitro. <I>PlGF</I> gene overexpression resulted in the opposite effects. Moreover, exogeneous PlGF-1 and PlGF-2 increased survival, migration, and invasiveness of RA-FLSs by binding their receptors, Flt-1 and neuropilin-1, and upregulating the expression of antiapoptotic molecules, pErk and Bcl2. Knockdown of <I>PlGF</I> transcripts reduced RA-FLS proliferation in a xenotransplantation model. Collectively, in addition to their role for neovascularization, PlGF-1 and -2 promote proliferation, survival, migration, and invasion of RA-FLSs in an autocrine and paracrine manner. These results demonstrated how primary cells of mesenchymal origin acquired an aggressive and transformed phenotype. PlGF and its receptors thus offer new targets for anti-FLS therapy.</P>