Project description:We found microRNA miR-23b was down-regulated in local inflammatory tissues of autoimmune disease such as RA, SLE and related mouse models such as CIA, lpr, EAE. Re-expression of miR-23b significantly inhibits autoimmune pathogenesis of CIA, Lpr and EAE. To identify potential targets of miR-23b, we use microarray gene-expression analysis to identify transcripts which could be repressed by miR-23b. RA: rheumatoid arthritis, CIA: Collagen-induced arthritis, SLE: systemic lupus erythematosus, EAE: experimental autoimmune encephalomyelitis We tansfected fibroblast-like synoviocytes (FLS) with mimic-miR-23b or mimic-NC.Cells were collected and total RNA was extracted for the Affymetrix GeneChip® Human Genome U133 Plus 2.0 Array
Project description:We found microRNA miR-23b was down-regulated in local inflammatory tissues of autoimmune disease such as RA, SLE and related mouse models such as CIA, lpr, EAE. Re-expression of miR-23b significantly inhibits autoimmune pathogenesis of CIA, Lpr and EAE. To identify potential targets of miR-23b, we use microarray gene-expression analysis to identify transcripts which could be repressed by miR-23b. RA: rheumatoid arthritis, CIA: Collagen-induced arthritis, SLE: systemic lupus erythematosus, EAE: experimental autoimmune encephalomyelitis
Project description:Interleukin-17A (IL-17A) is a key mediator of protective immunity to yeast and bacterial infections but also drives the pathogenesis of several autoimmune diseases, such as psoriasis or psoriatic arthritis. Here, we show that the tetra-transmembrane protein CMTM4 is a subunit of the IL-17 receptor (IL-17R). CMTM4 constitutively associated with IL-17R subunit C (IL-17RC) to mediate its stability, posttranslational modification, and plasma membrane localization. Both mouse and human cell lines deficient in CMTM4 were largely unresponsive to IL-17A, due to their inability to assemble the IL-17 receptor signaling complex. Accordingly, CMTM4-deficient mice were largely resistant to experimental psoriasis. Collectively, our data identified CMTM4 as an essential component of the IL-17 receptor and a potential therapeutic target for treating IL-17-mediated autoimmune diseases.
Project description:Interleukin 2 (IL-2), a cytokine linked to human autoimmune diseases, limits IL-17 production. We show that deletion of Stat3 in T cells abrogates IL-17 production and attenuates autoimmunity associated with IL-2 deficiency. While STAT3 induces IL-17 and RORγt and inhibits Foxp3, IL-2 inhibited IL-17 independently of Foxp3 and RORγt. We found that STAT3 and STAT5 bound to multiple common sites across the Il17 genetic locus. The induction of STAT5 binding by IL-2 was associated with a reduction in STAT3 binding at these sites and the inhibition of associated active epigenetic marks. Titrating the relative activation of STAT3 and STAT5 modulated TH17 cell specification. Thus, the balance rather than the absolute magnitude of these signals determines the propensity of cells to make a key inflammatory cytokine. The genome-wide binding of STAT3 and STAT5 under Th17 conditions was investigated by CHIP-seq.
Project description:Accelerated senescence in lung epithelial cells is known to play a key role in the pathogenesis of idiopathic pulmonary fibrosis (IPF). However, the exact mechanisms underlying the IPF-related epithelial cell phenotype have yet to be elucidated. Increasing evidence supports the concept that extracellular vesicles (EVs), including exosomes and microvesicles, mediate intercellular communication that contributes to diverse aspects of physiology and pathogenesis. Here, we demonstrate that lung fibroblasts (LFs) from IPF patients accelerate epithelial cell senescence via EV-mediated transfer of LF-derived pathogenic cargo to lung epithelial cells. Mechanistically, IPF LF-derived EVs increase mitochondrial reactive oxygen species (mtROS) and associated mitochondrial damage in lung epithelial cells, leading to mtROS-mediated activation of the DNA damage response and subsequent epithelial cell senescence. We show that IPF LF-derived EVs contain elevated levels of miR-23b-3p and miR-494-3p that are responsible for suppressing SIRT3, resulting in the EV-induced phenotypic changes of lung epithelial cells. Furthermore, we observe that miR-23b-3p and miR-494-3p expression increases in lung epithelial cells from IPF patients’ lungs. Finally, the levels of miR-23b-3p and 494-3p found in IPF LF-derived EVs correlate positively with IPF disease severity. These findings reveal that the accelerated epithelial cell mitochondrial damage and senescence observed during IPF pathogenesis are caused by a novel mechanism in which SIRT3 is suppressed by miR-containing EVs derived from IPF fibroblasts.
Project description:Introduction: To determine the miRNA expression profile in pregnancies complicated by Preeclampsia (PE) and compare it to uncomplicated pregnancies. Methods: Seventeen placentas from women with PE, [all of them being late onset PE (LOPE)], as well as 17 placentas from uncomplicated pregnancies were analyzed using miRNA NGS. For statistical analyses the MATLAB® simulation environment was applied. The expression of miR-99b and miR-23b were verified using Quantitative Real-Time Polymerase Chain Reaction. Results: Two miRNAs were found dysregulated in PE complicated placentas. Statistical analysis revealed that miR-99b and miR-23b were under-expressed in complicated placentas as compared to controls. Discussion: Since specific miRNAs can differentiate complicated from uncomplicated pregnancies, they may be considered as putative PE-specific biomarkers.
Project description:Interleukin 2 (IL-2), a cytokine linked to human autoimmune diseases, limits IL-17 production. We show that deletion of Stat3 in T cells abrogates IL-17 production and attenuates autoimmunity associated with IL-2 deficiency. While STAT3 induces IL-17 and RORγt and inhibits Foxp3, IL-2 inhibited IL-17 independently of Foxp3 and RORγt. We found that STAT3 and STAT5 bound to multiple common sites across the Il17 genetic locus. The induction of STAT5 binding by IL-2 was associated with a reduction in STAT3 binding at these sites and the inhibition of associated active epigenetic marks. Titrating the relative activation of STAT3 and STAT5 modulated TH17 cell specification. Thus, the balance rather than the absolute magnitude of these signals determines the propensity of cells to make a key inflammatory cytokine.
Project description:Interleukin 17 (IL-17) producing T helper 17 (Th17) cells are critical drivers of pathogenesis in a variety of autoimmune and inflammatory diseases. Strategies to mitigate excessive Th17 response thus remain an attractive target for immunotherapies. Here we report that Cancerous Inhibitor of Protein Phosphatase 2A (CIP2A) regulates IL-17 production by Th17 cells in human and mouse. Using CIP2A knock-out (KO) mice and siRNA-mediated CIP2A silencing in human primary CD4+ T cells, we demonstrated that CIP2A silencing results in a significant increase in IL-17 production. Interestingly, CIP2A deficient Th17 cells were characterized by increased strength and duration of STAT3 (Y705) phosphorylation. Genome-wide gene expression profile as well as the p-STAT3 (Y705) interactome of CIP2A deficient Th17 cells identified that CIP2A regulates the strength of the interaction between Acylglycerol kinase (AGK) and STAT3, and thereby, modulates STAT3 phosphorylation as well as expression of IL-17 in Th17 cells. Our results uncover the physiological function of CIP2A in Th17 cells and provides new opportunities for therapeutic intervention in Th17 cell mediated diseases.
Project description:The efficacy of monoclonal antibodies against either interleukin (IL)-17 or the IL-17 receptor in psoriasis therapy provides strong evidence that IL-17 is the major inflammatory mediation in this disease. However, how IL-17 induces epidermal hyperplasia in psoriasis remains largely unknown. Here, we show that IL-17 actives NF-kB in keratinocytes and initiates the NF-kB-dependent transcription of microRNA-31 (miR-31), one of the most abundant microRNAs in the epidermis of lesional skin of psoriasis and two related mouse models. Similar to IL-17 deficiency (IL-17-/-), knocking out miR-31 (miR-31-/-) or targeting it by antagomir-31 prevents keratinocytes Ki67 expression and inhibits acanthosis and dermal inflammation in psoriasis mouse model. Moreover, PPP6c, a negative regulator restricting G0/G1 to G2/M phase progression in the cell cycle, is diminished in human psoriatic epidermis and is directly targeted by miR-31. Inhibition of ppp6c is functionally important for the biological effects of miR-31 in the development of epidermal hyperplasia. Thus, our data define IL-17-inducede miR-31 and its target ppp6c as critical factors for hyperproliferative epidermis in psoriasis.
Project description:Accelerated senescence in lung epithelial cells is known to play a key role in the pathogenesis of idiopathic pulmonary fibrosis (IPF). However, the exact mechanisms underlying the IPF-related epithelial cell phenotype have yet to be elucidated. Increasing evidence supports the concept that extracellular vesicles (EVs), including exosomes and microvesicles, mediate intercellular communication that contributes to diverse aspects of physiology and pathogenesis. Here, we demonstrate that lung fibroblasts (LFs) from IPF patients accelerate epithelial cell senescence via EV-mediated transfer of LF-derived pathogenic cargo to lung epithelial cells. Mechanistically, IPF LF-derived EVs increase mitochondrial reactive oxygen species (mtROS) and associated mitochondrial damage in lung epithelial cells, leading to mtROS-mediated activation of the DNA damage response and subsequent epithelial cell senescence. We show that IPF LF-derived EVs contain elevated levels of miR-23b-3p and miR-494-3p that are responsible for suppressing SIRT3, resulting in the EV-induced phenotypic changes of lung epithelial cells. Furthermore, we observe that miR-23b-3p and miR-494-3p expression increases in lung epithelial cells from IPF patients’ lungs. Finally, the levels of miR-23b-3p and 494-3p found in IPF LF-derived EVs correlate positively with IPF disease severity. These findings reveal that the accelerated epithelial cell mitochondrial damage and senescence observed during IPF pathogenesis are caused by a novel mechanism in which SIRT3 is suppressed by miR-containing EVs derived from IPF fibroblasts.