Long non-coding RNA H19X as a regulator of mononuclear cell adhesion to the endothelium in systemic sclerosis.

OBJECTIVE: To define the functional relevance of H19 X-linked co-expressed lncRNA (H19X) in endothelial cell (EC) activation as a key process in systemic sclerosis (SSc) vasculopathy. METHODS: H19X expression in SSc skin biopsies was analyzed from single cell RNA sequencing (scRNA-seq) data. Differential expression and pathway enrichment analysis between cells expressing (H19Xpos) and non expressing H19X (H19Xneg) cells was performed. H19X function was investigated in human dermal microvascular EC (HDMECs) by silencing. H19X and EC adhesion molecules levels were analyzed by RT-qPCR and Western Blot after stimulation with proinflammatory cytokines. Cytoskeletal rearrangements were analyzed by fluorescent staining. Endothelial adhesion was evaluated by co-culture of HDMECs and fluorescent labelled peripheral blood mononuclear cells (PBMCs). Shedding VCAM1 was evaluated by ELISA on HDMEC supernatant. RESULTS: scRNA-seq showed significant upregulation of H19X in SSc compared with healthy EC. In HDMEC, H19X was consistently induced by type I and II interferons. H19X knockdown lead to a significant decrease of the mRNA of several adhesion molecules. Particularly, vascular cell adhesion protein 1 (VCAM1) was significantly reduced at protein and mRNA levels. Co-expression analysis of the scRNA-seq data confirmed a higher expression of VCAM1 in (H19Xpos) EC. EC were also strongly associated with the 'cell adhesion molecule' pathway. Moreover, VCAM1 downstream pathway displayed less activation following H19X knockdown. Contractility of HDMEC, PBMC adhesion to HDMEC and VCAM1 shedding were also reduced following H19X knockdown. CONCLUSIONS: lncRNA H19X may contribute to EC activation in SSc vasculopathy, acting as a regulator of expression of adhesion molecules in EC.

TNF-α protects from exacerbated myocarditis and cardiac death by suppressing expansion of activated heart-reactive CD4+ T cells.

AIMS: Tumour necrosis factor α (TNF-α) represents a classical pro-inflammatory cytokine, and its increased levels positively correlate with the severity of many cardiovascular diseases. Surprisingly, some heart failure patients receiving high doses of anti-TNF-α antibodies showed serious health worsening. This work aimed to examine the role of TNF-α signalling on the development and progression of myocarditis and heart-specific autoimmunity. METHODS AND RESULTS: Mice with genetic deletion of TNF-α (Tnf+/- and Tnf-/-) and littermate controls (Tnf+/+) were used to study myocarditis in the inducible and the transgenic T cell receptor (TCRM) models. Tnf+/- and Tnf-/- mice immunized with α-myosin heavy chain peptide (αMyHC) showed reduced myocarditis incidence, but the susceptible animals developed extensive inflammation in the heart. In the TCRM model, defective TNF-α production was associated with increased mortality at a young age due to cardiomyopathy and cardiac fibrosis. We could confirm that TNF-α as well as the secretome of antigen-activated heart-reactive effector CD4+ T (Teff) cells effectively activated the adhesive properties of cardiac microvascular endothelial cells (cMVECs). Our data suggested that TNF-α produced by endothelial in addition to Teff cells promoted leucocyte adhesion to activated cMVECs. Analysis of CD4+ T lymphocytes from both models of myocarditis showed a strongly increased fraction of Teff cells in hearts, spleens, and in the blood of Tnf+/- and Tnf-/- mice. Indeed, antigen-activated Tnf-/- Teff cells showed prolonged long-term survival and TNF-α cytokine-induced cell death of heart-reactive Teff. CONCLUSION: TNF-α signalling promotes myocarditis development by activating cardiac endothelial cells. However, in the case of established disease, TNF-α protects from exacerbating cardiac inflammation by inducing activation-induced cell death of heart-reactive Teff. These data might explain the lack of success of standard anti-TNF-α therapy in heart failure patients and open perspectives for T cell-targeted approaches.

The long non-coding RNA HOTAIR contributes to joint-specific gene expression in rheumatoid arthritis.

Although patients with rheumatoid arthritis (RA) typically exhibit symmetrical joint involvement, some patients develop alternative disease patterns in response to treatment, suggesting that different molecular mechanism may underlie disease progression depending on joint location. Here, we identify joint-specific changes in RA synovium and synovial fibroblasts (SF) between knee and hand joints. We show that the long non-coding RNA HOTAIR, which is only expressed in knee SF, regulates more than 50% of this site-specific gene expression in SF. HOTAIR is downregulated after stimulation with pro-inflammatory cytokines and is expressed at lower levels in knee samples from patients with RA, compared with osteoarthritis. Knockdown of HOTAIR in knee SF increases PI-Akt signalling and IL-6 production, but reduces Wnt signalling. Silencing HOTAIR inhibits the migratory function of SF, decreases SF-mediated osteoclastogenesis, and increases the recruitment of B cells by SF. We propose that HOTAIR is an important epigenetic factor in joint-specific gene expression in RA.

What Matters in a Relationship-Age, Sexual Satisfaction, Relationship Length, and Interpersonal Closeness as Predictors of Relationship Satisfaction in Young Adults.

Relationship satisfaction is one of the key elements affecting overall life satisfaction. This study aimed to identify significant predictors of relationship satisfaction in young adults in a romantic relationship. The study was questionnaire-based, involving 237 young adults who were currently in a relationship. Three self-rating scales were used: CSI-32 Relationship Satisfaction Scale, Sexual Satisfaction Questionnaire, and Unidimensional Relationship Closeness Scale. Sexual satisfaction proved to be a main predictor of relationship satisfaction in both sexes. For women, interpersonal closeness was additionally important, with a sense of closeness found to be even more important than sexual satisfaction for women cohabiting with their partners. Cohabiting people are generally more satisfied with their relationship, and a higher level of closeness and applied caresses can additionally be observed in them. In contrast, the relationship length appeared to matter only for men living with their partner: they were more satisfied with the relationship at the beginning of the relationship, and then their level of satisfaction declined. Relationship satisfaction in young adults appears to be determined by other factors depending on gender and cohabitation status. Nevertheless, at this age, sexual satisfaction proves to be one of the most critical factors for a sense of relationship satisfaction.

The AP-1 transcription factor Fosl-2 drives cardiac fibrosis and arrhythmias under immunofibrotic conditions.

Fibrotic changes in the myocardium and cardiac arrhythmias represent fatal complications in systemic sclerosis (SSc), however the underlying mechanisms remain elusive. Mice overexpressing transcription factor Fosl-2 (Fosl-2tg) represent animal model of SSc. Fosl-2tg mice showed interstitial cardiac fibrosis, disorganized connexin-43/40 in intercalated discs and deregulated expression of genes controlling conduction system, and developed higher heart rate (HR), prolonged QT intervals, arrhythmias with prevalence of premature ventricular contractions, ventricular tachycardias, II-degree atrio-ventricular blocks and reduced HR variability. Following stimulation with isoproterenol Fosl-2tg mice showed impaired HR response. In contrast to Fosl-2tg, immunodeficient Rag2-/-Fosl-2tg mice were protected from enhanced myocardial fibrosis and ECG abnormalities. Transcriptomics analysis demonstrated that Fosl-2-overexpression was responsible for profibrotic signature of cardiac fibroblasts, whereas inflammatory component in Fosl-2tg mice activated their fibrotic and arrhythmogenic phenotype. In human cardiac fibroblasts FOSL-2-overexpression enhanced myofibroblast signature under proinflammatory or profibrotic stimuli. These results demonstrate that under immunofibrotic conditions transcription factor Fosl-2 exaggerates myocardial fibrosis, arrhythmias and aberrant response to stress.

Effects of faecal microbiota transplantation on the small intestinal mucosa in systemic sclerosis.

OBJECTIVES: In SSc, gastrointestinal tract (GIT) involvement is a major concern, with no disease-modifying and limited symptomatic therapies available. Faecal microbiota transplantation (FMT) represents a new therapeutic option for GIT-affliction in SSc, showing clinical promise in a recent controlled pilot trial. Here, we aim to investigate effects of FMT on duodenal biopsies collected from SSc patients by immunohistochemistry and transcriptome profiling. METHODS: We analysed duodenal biopsies obtained pre-intervention (week 0) and post-intervention (weeks 2 and 16) from nine SSc patients receiving an intestinal infusion of FMT (n = 5) or placebo (n = 4). The analysis included immunohistochemistry (IHC) with a selected immune function and fibrosis markers, and whole biopsy transcriptome profiling. RESULTS: In patients receiving FMT, the number of podoplanin- and CD64-expressing cells in the mucosa were lower at week 2 compared with baseline. This decline in podoplanin- (r = 0.94) and CD64-positive (r = 0.89) cells correlated with improved patient-reported lower GIT symptoms. Whole biopsy transcriptome profiling from week 2 showed significant enrichment of pathways critical for cellular and endoplasmic reticulum stress responses, microvillus and secretory vesicles, vascular and sodium-dependent transport, and circadian rhythm. At week 16, we found enrichment of pathways mandatory for binding activity of immunoglobulin receptors, T cell receptor complexes, and chemokine receptors, as well as response to zinc-ions. We found that 25 genes, including Matrix metalloproteinase-1 were upregulated at both week 2 and week 16. CONCLUSION: Combining selective IHC and unbiased gene expression analyses, this exploratory study highlights the potential for disease-relevant organ effects of FMT in SSc patients with GIT involvement. TRIAL REGISTRATION: ClinicalTrials.gov, http://clinicaltrials.gov, NCT03444220.

Persistent organic pollutants affect steroidogenic and apoptotic activities in granulosa cells and reactive oxygen species concentrations in oocytes in the mouse.

CONTEXT: The destruction of granulosa cells (GCs), the main functional cell type in the ovary, prevents steroid hormone production, which in turn may damage oocytes, resulting in ovarian failure. The accumulation of a number of persistent organic pollutants (POPs) in the ovarian follicular fluid (FF) has been documented, which raises serious questions regarding their impact on female fertility. AIMS: We aimed to determine whether a mixture of POPs reflecting the profile found in FF influences mouse GCs or oocyte function and viability. METHODS: A mixture of POPs, comprising perfluorooctanoate, perfluorooctane sulfonate, 2,2-dichlorodiphenyldichloroethylene, polychlorinated biphenyl 153, and hexachlorobenzene, was used. In addition to using the exact concentration of POPs previously measured in human FF, we tested two other mixtures, one with10-fold lower and another with 10-fold higher concentrations of each POP. KEY RESULTS: Steroidogenesis was disrupted in GCs by the POP mixture, as demonstrated by lower oestradiol and progesterone secretion and greater lipid droplet accumulation. Furthermore, the POP mixture reduced GC viability and increased apoptosis, assessed using caspase-3 activity. The POP mixture significantly increased the number of oocytes that successfully progressed to the second meiotic metaphase and the oocyte reactive oxygen species (ROS) concentration. CONCLUSIONS: Thus, a mixture of POPs that are typically present in human FF has detrimental effects on ovarian function: it reduces the viability of GCs, and increases the oocyte concentrations of ROS. IMPLICATIONS: These results indicate that chronic exposure to POPs adversely affects female reproductive health.

T Lymphocyte-Derived Exosomes Transport MEK1/2 and ERK1/2 and Induce NOX4-Dependent Oxidative Stress in Cardiac Microvascular Endothelial Cells.

Background: Activation of endothelial cells by inflammatory mediators secreted by CD4+ T lymphocytes plays a key role in the inflammatory response. Exosomes represent a specific class of signaling cues transporting a mixture of proteins, nucleic acids, and other biomolecules. So far, the impact of exosomes shed by T lymphocytes on cardiac endothelial cells remained unknown. Methods and Results: Supernatants of CD4+ T cells activated with anti-CD3/CD28 beads were used to isolate exosomes by differential centrifugation. Activation of CD4+ T cells enhanced exosome production, and these exosomes (CD4-exosomes) induced oxidative stress in cardiac microvascular endothelial cells (cMVECs) without affecting their adhesive properties. Furthermore, CD4-exosome treatment aggravated the generation of mitochondrial reactive oxygen species (ROS), reduced nitric oxide (NO) levels, and enhanced the proliferation of cMVECs. These effects were reversed by adding the antioxidant apocynin. On the molecular level, CD4-exosomes increased NOX2, NOX4, ERK1/2, and MEK1/2 in cMVECs, and ERK1/2 and MEK1/2 proteins were found in CD4-exosomes. Inhibition of either MEK/ERK with U0126 or ERK with FR180204 successfully protected cMVECs from increased ROS levels and reduced NO bioavailability. Treatment with NOX1/4 inhibitor GKT136901 effectively blocked excessive ROS and superoxide production, reversed impaired NO levels, and reversed enhanced cMVEC proliferation triggered by CD4-exosomes. The siRNA-mediated silencing of Nox4 in cMVECs confirmed the key role of NOX4 in CD4-exosome-induced oxidative stress. To address the properties of exosomes under inflammatory conditions, we used the mouse model of CD4+ T cell-dependent experimental autoimmune myocarditis. In contrast to exosomes obtained from control hearts, exosomes obtained from inflamed hearts upregulated NOX2, NOX4, ERK1/2, MEK1/2, increased ROS and superoxide levels, and reduced NO bioavailability in treated cMVECs, and these changes were reversed by apocynin. Conclusion: Our results point to exosomes as a novel class of bioactive factors secreted by CD4+ T cells in immune response and represent potential important triggers of NOX4-dependent endothelial dysfunction. Neutralization of the prooxidative aspect of CD4-exosomes could open perspectives for the development of new therapeutic strategies in inflammatory cardiovascular diseases.

Dersimelagon, a novel oral melanocortin 1 receptor agonist, demonstrates disease-modifying effects in preclinical models of systemic sclerosis.

BACKGROUND: Activation of melanocortin 1 receptor (MC1R) is known to exert broad anti-inflammatory and anti-fibrotic effects. The purpose of this study is to investigate the potential of dersimelagon, a novel oral MC1R agonist, as a therapeutic agent for systemic sclerosis (SSc). METHODS: The effects of dersimelagon phosphoric acid (MT-7117) on skin fibrosis and lung inflammation were evaluated in bleomycin (BLM)-induced SSc murine models that were optimized for prophylactic and therapeutic evaluation. Microarray-based gene expression analysis and serum protein profiling were performed in the BLM-induced SSc models. The effect of MT-7117 on transforming growth factor-ß (TGF-ß)-induced activation of human dermal fibroblasts was evaluated in vitro. Immunohistochemical analyses of MC1R expression in the skin of SSc patients were performed. RESULTS: Prophylactic treatment with MT-7117 (≥ 0.3 mg/kg/day p.o.) significantly inhibited skin fibrosis and lung inflammation, and therapeutic treatment with MT-7117 (≥ 3 mg/kg/day p.o.) significantly suppressed the development of skin fibrosis in the BLM-induced SSc models. Gene array analysis demonstrated that MT-7117 exerts an anti-inflammatory effect via suppression of the activation of inflammatory cells and inflammation-related signals; additionally, vascular dysfunction was extracted as the pathology targeted by MT-7117. Serum protein profiling revealed that multiple SSc-related biomarkers including P-selectin, osteoprotegerin, cystatin C, growth and differentiation factor-15, and S100A9 were suppressed by MT-7117. MT-7117 inhibited the activation of human dermal fibroblasts by suppressing TGF-ß-induced ACTA2 (encoding α-smooth muscle actin) mRNA elevation. MC1R was expressed by monocytes/macrophages, neutrophils, blood vessels (endothelial cells), fibroblasts, and epidermis (keratinocytes) in the skin of SSc patients, suggesting that these MC1R-positive cells could be targets for MT-7117. CONCLUSIONS: MT-7117 demonstrates disease-modifying effects in preclinical models of SSc. Investigations of its mechanism of action and target expression analyses indicate that MT-7117 exerts its positive effect by affecting inflammation, vascular dysfunction, and fibrosis, which are all key pathologies of SSc. The results of the present study suggest that MT-7117 is a potential therapeutic agent for SSc. A phase 2 clinical trial investigating the efficacy and tolerability of MT-7117 in patients with early, progressive diffuse cutaneous SSc is currently in progress.

Masquerade of Polish Society-Psychological Determinants of COVID-19 Precautionary Behaviors.

The risk of contracting COVID-19 was a very specific situation of uncertainty and ambi-guity, and of course, cognitively interesting for psychologists studying the determinants of behaviors of different personality types. In this study, we set our sights on trying to find a correlation between adherence to wearing masks and receiving vaccinations and having certain character traits that we thought might influence preventive behavior or not. We focused on the Dark Triad-psychopathy, Machiavellianism and narcissism-as well as social approval and the need for cognition closure, as these traits have previously been linked to heightened conspiracy mentalities. We recruited 159 subjects in the experiment, including 53 male and 106 female participants over the age of 18 to take part in an online survey investigating personality and COVID-19 information. The results confirmed our hypothesis that age, empathy, the need for social approval and other psychological traits are the factors that differentiates people who wear face masks from those who do not. However, it seems impossible to define one set of features that would predispose people to not wear face masks. In our study, the importance of psychological features differed depending on the category of public places. We discuss possible implications of these findings and provide direction for future research.

Potential Factors Conditioning the Compliance to Mandatory Face Covering in the Public Space Due to SARS-CoV-2 Pandemic.

BACKGROUND: During the SARS-CoV-2 pandemic, we could observe different attitudes towards restrictive bans and orders. AIM: The research aimed to examine the potential psychological factors, such as generalized anxiety, fear of COVID-19 or social approval, related to the approach to mandatory face covering in public spaces. METHODS: The web-assisted interviews survey was used among 202 participants, which included socio-demographical data, approach to face covering, the Generalized Anxiety Disorder Scale, the COVID-19 Anxiety Scale, and The Questionnaire of Social Approval. RESULT: The data showed a statistically significant correlation between compliance to the rule of face and nose covering vs. anxiety and compliance to the rule of face and nose covering vs. generalized anxiety. The results indicate differences between vaccinated and non-vaccinated people in the anxiety of COVID-19, generalized anxiety, and compliance with the rule of face and nose covering. CONCLUSIONS: People vaccinated has a higher level of anxiety and more often compliance with the rule of face covering. It is worth noting that an overly pronounced fear of COVID-19 could be a risk factor for mental health. More research about coping with anxiety in the group of vaccinated people is recommended.

Angiotensin II receptor 1 controls profibrotic Wnt/ß-catenin signalling in experimental autoimmune myocarditis.

AIMS: Angiotensin (Ang) II signalling has been suggested to promote cardiac fibrosis in inflammatory heart diseases; however, the underlying mechanisms remain obscure. Using Agtr1a-/- mice with genetic deletion of angiotensin receptor type 1 (ATR1) and the experimental autoimmune myocarditis (EAM) model, we aimed to elucidate the role of Ang II-ATR1 pathway in development of heart-specific autoimmunity and post-inflammatory fibrosis. METHODS AND RESULTS: EAM was induced in wild-type (WT) and Agtr1a-/- mice by subcutaneous injections with alpha myosin heavy chain peptide emulsified in complete Freund's adjuvant. Agtr1a-/- mice developed myocarditis to a similar extent as WT controls at day 21 but showed reduced fibrosis and better systolic function at day 40. Crisscross bone marrow chimaera experiments proved that ATR1 signalling in the bone marrow compartment was critical for cardiac fibrosis. Heart infiltrating, bone-marrow-derived cells produced Ang II, but lack of ATR1 in these cells reduced transforming growth factor beta (TGF-ß)-mediated fibrotic responses. At the molecular level, Agtr1a-/- heart-inflammatory cells showed impaired TGF-ß-mediated phosphorylation of Smad2 and TAK1. In WT cells, TGF-ß induced formation of RhoA-GTP and RhoA-A-kinase anchoring protein-Lbc (AKAP-Lbc) complex. In Agtr1a-/- cells, stabilization of RhoA-GTP and interaction of RhoA with AKAP-Lbc were largely impaired. Furthermore, in contrast to WT cells, Agtr1a-/- cells stimulated with TGF-ß failed to activate canonical Wnt pathway indicated by suppressed activity of glycogen synthase kinase-3 (GSK-3)ß and nuclear ß-catenin translocation and showed reduced expression of Wnts. In line with these in vitro findings, ß-catenin was detected in inflammatory regions of hearts of WT, but not Agtr1a-/- mice and expression of canonical Wnt1 and Wnt10b were lower in Agtr1a-/- hearts. CONCLUSION: Ang II-ATR1 signalling is critical for development of post-inflammatory fibrotic remodelling and dilated cardiomyopathy. Our data underpin the importance of Ang II-ATR1 in effective TGF-ß downstream signalling response including activation of profibrotic Wnt/ß-catenin pathway.

Elevated Fibronectin Levels in Profibrotic CD14+ Monocytes and CD14+ Macrophages in Systemic Sclerosis.

Background: Systemic sclerosis (SSc) is an autoimmune disease characterized by overproduction of extracellular matrix (ECM) and multiorgan fibrosis. Animal studies pointed to bone marrow-derived cells as a potential source of pathological ECM-producing cells in immunofibrotic disorders. So far, involvement of monocytes and macrophages in the fibrogenesis of SSc remains poorly understood. Methods and Results: Immunohistochemistry analysis showed accumulation of CD14+ monocytes in the collagen-rich areas, as well as increased amount of alpha smooth muscle actin (αSMA)-positive fibroblasts, CD68+ and mannose-R+ macrophages in the heart and lungs of SSc patients. The full genome transcriptomics analyses of CD14+ blood monocytes revealed dysregulation in cytoskeleton rearrangement, ECM remodeling, including elevated FN1 (gene encoding fibronectin) expression and TGF-ß signalling pathway in SSc patients. In addition, single cell RNA sequencing analysis of tissue-resident CD14+ pulmonary macrophages demonstrated activated profibrotic signature with the elevated FN1 expression in SSc patients with interstitial lung disease. Peripheral blood CD14+ monocytes obtained from either healthy subjects or SSc patients exposed to profibrotic treatment with profibrotic cytokines TGF-ß, IL-4, IL-10, and IL-13 increased production of type I collagen, fibronectin, and αSMA. In addition, CD14+ monocytes co-cultured with dermal fibroblasts obtained from SSc patients or healthy individuals acquired a spindle shape and further enhanced production of profibrotic markers. Pharmacological blockade of the TGF-ß signalling pathway with SD208 (TGF-ß receptor type I inhibitor), SIS3 (Smad3 inhibitor) or (5Z)-7-oxozeaenol (TGF-ß-activated kinase 1 inhibitor) ameliorated fibronectin levels and type I collagen secretion. Conclusions: Our findings identified activated profibrotic signature with elevated production of profibrotic fibronectin in CD14+ monocytes and CD14+ pulmonary macrophages in SSc and highlighted the capability of CD14+ monocytes to acquire a profibrotic phenotype. Taking together, tissue-infiltrating CD14+ monocytes/macrophages can be considered as ECM producers in SSc pathogenesis.

WNT/ß-Catenin Signaling Promotes TGF-ß-Mediated Activation of Human Cardiac Fibroblasts by Enhancing IL-11 Production.

Cardiac fibrosis is a pathological process associated with the development of heart failure. TGF-ß and WNT signaling have been implicated in pathogenesis of cardiac fibrosis, however, little is known about molecular cross-talk between these two pathways. The aim of this study was to examine the effect of exogenous canonical WNT3a and non-canonical WNT5a in TGF-ß-activated human cardiac fibroblasts. We found that WNT3a and TGF-ß induced a ß-catenin-dependent response, whereas WNT5a prompted AP-1 activity. TGF-ß triggered profibrotic signatures in cardiac fibroblasts, and co-stimulation with WNT3a or co-activation of the ß-catenin pathway with the GSK3ß inhibitor CHIR99021 enhanced collagen I and fibronectin production and development of active contractile stress fibers. In the absence of TGF-ß, neither WNT3a nor CHIR99021 exerted profibrotic responses. On a molecular level, in TGF-ß-activated fibroblasts, WNT3a enhanced phosphorylation of TAK1 and production and secretion of IL-11 but showed no effect on the Smad pathway. Neutralization of IL-11 activity with the blocking anti-IL-11 antibody effectively reduced the profibrotic response of cardiac fibroblasts activated with TGF-ß and WNT3a. In contrast to canonical WNT3a, co-activation with non-canonical WNT5a suppressed TGF-ß-induced production of collagen I. In conclusion, WNT/ß-catenin signaling promotes TGF-ß-mediated fibroblast-to-myofibroblast transition by enhancing IL-11 production. Thus, the uncovered mechanism broadens our knowledge on a molecular basis of cardiac fibrogenesis and defines novel therapeutic targets for fibrotic heart diseases.

The AP-1 Transcription Factor Fosl-2 Regulates Autophagy in Cardiac Fibroblasts during Myocardial Fibrogenesis.

BACKGROUND: Pathological activation of cardiac fibroblasts is a key step in development and progression of cardiac fibrosis and heart failure. This process has been associated with enhanced autophagocytosis, but molecular mechanisms remain largely unknown. METHODS AND RESULTS: Immunohistochemical analysis of endomyocardial biopsies showed increased activation of autophagy in fibrotic hearts of patients with inflammatory cardiomyopathy. In vitro experiments using mouse and human cardiac fibroblasts confirmed that blockade of autophagy with Bafilomycin A1 inhibited fibroblast-to-myofibroblast transition induced by transforming growth factor (TGF)-ß. Next, we observed that cardiac fibroblasts obtained from mice overexpressing transcription factor Fos-related antigen 2 (Fosl-2tg) expressed elevated protein levels of autophagy markers: the lipid modified form of microtubule-associated protein 1A/1B-light chain 3B (LC3BII), Beclin-1 and autophagy related 5 (Atg5). In complementary experiments, silencing of Fosl-2 with antisense GapmeR oligonucleotides suppressed production of type I collagen, myofibroblast marker alpha smooth muscle actin and autophagy marker Beclin-1 in cardiac fibroblasts. On the other hand, silencing of either LC3B or Beclin-1 reduced Fosl-2 levels in TGF-ß-activated, but not in unstimulated cells. Using a cardiac hypertrophy model induced by continuous infusion of angiotensin II with osmotic minipumps, we confirmed that mice lacking either Fosl-2 (Ccl19CreFosl2flox/flox) or Atg5 (Ccl19CreAtg5flox/flox) in stromal cells were protected from cardiac fibrosis. CONCLUSION: Our findings demonstrate that Fosl-2 regulates autophagocytosis and the TGF-ß-Fosl-2-autophagy axis controls differentiation of cardiac fibroblasts. These data provide a new insight for the development of pharmaceutical targets in cardiac fibrosis.

Regulation of Monocyte Adhesion and Type I Interferon Signaling by CD52 in Patients With Systemic Sclerosis.

OBJECTIVE: Systemic sclerosis (SSc) is characterized by dysregulation of type I interferon (IFN) signaling. CD52 is known for its immunosuppressive functions in T cells. This study was undertaken to investigate the role of CD52 in monocyte adhesion and type I IFN signaling in patients with SSc. METHODS: Transcriptome profiles of circulating CD14+ monocytes from patients with limited cutaneous SSc (lcSSc), patients with diffuse cutaneous SSc (dcSSs), and healthy controls were analyzed by RNA sequencing. Levels of CD52, CD11b/integrin αΜ, and CD18/integrin ß2 in whole blood were assessed by flow cytometry. CD52 expression was analyzed in relation to disease phenotype (early, lcSSc, dcSSc) and autoantibody profiles. The impact of overexpression, knockdown, and antibody blocking of CD52 was analyzed by gene and protein expression assays and functional assays. RESULTS: Pathway enrichment analysis indicated an increase in adhesion- and type I IFN-related genes in monocytes from SSc patients. These cells displayed up-regulated expression of CD11b/CD18, reduced expression of CD52, and enhanced adhesion to intercellular adhesion molecule 1 and endothelial cells. Changes in CD52 expression were consistent with the SSc subtypes, as well as with immunosuppressive treatments, autoantibody profiles, and monocyte adhesion properties in patients with SSc. Overexpression of CD52 led to decreased levels of CD18 and monocyte adhesion, while knockdown of CD52 increased monocyte adhesion. Experiments with the humanized anti-CD52 monoclonal antibody alemtuzumab in blood samples from healthy controls increased monocyte adhesion and CD11b/CD18 expression, and enhanced type I IFN responses. Monocytic CD52 expression was up-regulated by interleukin-4 (IL-4)/IL-13 via the STAT6 pathway, and was down-regulated by lipopolysaccharide and IFNs α, ß, and γ in a JAK1 and histone deacetylase IIa (HDAC IIa)-dependent manner. CONCLUSION: Down-regulation of the antiadhesion CD52 antigen in CD14+ monocytes represents a novel mechanism in the pathogenesis of SSc. Targeting of the IFN-HDAC-CD52 axis in monocytes might represent a new therapeutic option for patients with early SSc.