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Systemic sclerosis (SSc) is one of these diseases, both chronic and complex, whose evolution can be fatal and whose clinical repercussions, variable from one patient to another, can result in a profound alteration of autonomy and quality of life. These two scores reflect respectively the disability induced by SSc and the probability of improvement in response to treatment in patients with early diffuse cutaneous SSc. Keywords: systemic sclerosis; pathophysiology; co-stimulation; abatacept; innate immune system; mesenchymal stromal cell; extracellular vesicles; cancer EN systemic sclerosis pathophysiology co-stimulation abatacept innate immune system mesenchymal stromal cell extracellular vesicles cancer 1 4 4 10/04/21 20210930 NES 210930 In these times of Covid-19 pandemic, during which medical research is mobilized in the fight against the coronavirus, patients continue to suffer from other acute and chronic diseases and research on them must continue. [Extracted from the article]

Objectives: Skin fibrosis is the hallmark of systemic sclerosis (SSc) a rare intractable disease with unmet medical need. We previously reported the anti-fibrotic potential of mesenchymal stem cells (MSCs) in a murine model of SSc. This model, based on daily intra-dermal injections of hypochlorite (HOCl) during 6 weeks, is an inducible model of the disease. Herein, we aimed at characterizing the development of skin fibrosis in HOCl-induced SSc (HOCl-SSc), and evaluating the impact of MSC infusion during the fibrogenesis process. Methods: After HOCl-SSc induction in BALB/c mice, clinical, histological and biological parameters were measured after 3 weeks (d21) and 6 weeks (d42) of HOCl challenge, and 3 weeks after HOCl discontinuation (d63). Treated-mice received infusions of 2.5 × 105 MSCs 3 weeks before sacrifice (d0, d21, d42). Results: HOCl injections induced a two-step process of fibrosis development: first, an 'early inflammatory phase', characterized at d21 by highly proliferative infiltrates of myofibroblasts, T-lymphocytes and macrophages. Second, a phase of 'established matrix fibrosis', characterized at d42 by less inflammation, but strong collagen deposition and followed by a third phase of 'spontaneous tissue remodeling' after HOCl discontinuation. This phase was characterized by partial fibrosis receding, due to enhanced MMP1/TIMP1 balance. MSC treatment reduced skin thickness in the three phases of fibrogenesis, exerting more specialized mechanisms: immunosuppression, abrogation of myofibroblast activation, or further enhancing tissue remodeling, depending on the injection time-point. Conclusion: HOCl-SSc mimics three fibrotic phenotypes of scleroderma, all positively impacted by MSC therapy, demonstrating the great plasticity of MSC, a promising cure for SSc. [ABSTRACT FROM AUTHOR]

Objective. To evaluate the influenza vaccination rate and factors influencing it in patients with SSc. [ABSTRACT FROM PUBLISHER]

Systemic sclerosis (SSc) is a complex disorder resulting from dysregulated interactions between the three main pathophysiological axes: fibrosis, immune dysfunction, and vasculopathy, with no specific treatment available to date. Adipose tissue-derived mesenchymal stromal cells (ASCs) and their extracellular vesicles (EVs) have proved efficacy in pre-clinical murine models of SSc. However, their precise action mechanism is still not fully understood. Because of the lack of availability of fibroblasts isolated from SSc patients (SSc-Fb), our aim was to determine whether a TGFβ1-induced model of human myofibroblasts (Tβ-Fb) could reproduce the characteristics of SSc-Fb and be used to evaluate the anti-fibrotic function of ASCs and their EVs. We found out that Tβ-Fb displayed the main morphological and molecular features of SSc-Fb, including the enlarged hypertrophic morphology and expression of several markers associated with the myofibroblastic phenotype. Using this model, we showed that ASCs were able to regulate the expression of most myofibroblastic markers on Tβ-Fb and SSc-Fb, but only when pre-stimulated with TGFβ1. Of interest, ASC-derived EVs were more effective than parental cells for improving the myofibroblastic phenotype. In conclusion, we provided evidence that Tβ-Fb are a relevant model to mimic the main characteristics of SSc fibroblasts and investigate the mechanism of action of ASCs. We further reported that ASC-EVs are more effective than parental cells suggesting that the TGFβ1-induced pro-fibrotic environment may alter the function of ASCs. [ABSTRACT FROM AUTHOR]

Cancer among patients with systemic sclerosis (SSc) would appear to be more prevalent than in the general population. Pathophysiological hypotheses are multiple, involving intertwined factors such as immune system antitumoral response, oxygen species dysregulation, and immunosuppressive treatments. We aimed to identify SSc patients with cancer monitored at our center, describing their clinical and immunological characteristics, such as cancer-specific outcomes. We focused in particular on the temporal relationships between cancer onset and SSc diagnosis. A retrospective study was conducted on SSc patients from Montpellier University Hospital from 2003 to 2018. Clinical characteristics and outcomes of each SSc patient with cancer were recorded. Fifty-five patients with SSc and at least one cancer was included (median age 56 years (47–66)), with a median follow-up time of 11 years (4–15). Sixty-four metachronous malignancies were identified (12 patients had two cancers). Among them, early-onset cancer occurrences (±5 years from SSc diagnosis) included 23 cancers (39% breast cancers, 13% lung cancers, and 13% gastro-intestinal tract cancers). Twenty-two cancers occurred 10 years (±5 years) after SSc diagnosis (14% breast cancers, 23% gastrointestinal (GI) tract cancers, and 18% lung cancers). Patients without any of the two autoantibodies (anti-centromere (ACA) and anti-topoisomerase (ATA-scl70) antibodies) were more prevalent in the early-onset cancer subgroup (14 vs. 6, p = 0.02). This study brought to light two peaks of cancer occurrence in SSc patients. Early-onset cancers were associated with SSc with a specific immunological signature. Late-onset cancers might be the consequence of a subtle interplay between repeated target organ inflammation, immunosuppressant use, mesenchymal cell dysfunction and subsequent genetic alterations. [ABSTRACT FROM AUTHOR]

Abstract: In order to improve the detection of antitopoisomerase 1 antibodies in a cohort of 111 systemic sclerosis patients, we have performed immunoblots on protein extracts of HEp-2 cells. Using indirect immunofluorescence and ELISA, 27 patients (24.3%) had antitopoisomerase 1 antibodies, 32 (28.8%) had anticentromere antibodies, 31 (27.9%) had antinuclear antibodies with none of these two antibodies and 21 (18.9%) had no antinuclear antibody. IgG from 24/27 (88.9%) patients with antitopoisomerase 1 antibodies bound to 2 protein bands of 63 and 100 kDa identified as topoisomerase 1 by N-terminal sequencing. Antitopoisomerase 1 antibodies were detected in 9 (8.1%) patients who had no antitopoisomerase 1 antibody as determined by ELISA. Patients with antitopoisomerase 1 antibodies had an almost similar phenotype without distinction between ELISA or immunoblot approaches. Our results provide evidence for the use of a combination of ELISA and immunoblot approaches for the detection of antitopoisomerase 1 antibodies. [Copyright &y& Elsevier]

Abstract: By using a quantitative immunoblotting technique on protein extracts of human macrovascular and microvascular endothelial cells, we have analyzed the self-reactive repertoires of IgG from 20 patients with limited cutaneous SSc, 40 patients with diffuse SSc and 60 age- and sex-matched healthy controls. Serum IgG from 15/20 patients with limited cutaneous SSc and anti-centromere antibodies bound to at least one of the two 75- and 85-kDa protein bands in the different endothelial cell extracts, whereas IgG from healthy controls or patients with diffuse SSc did not. N-terminal sequencing of the 75- and 85-kDa bands identified CENP-B as the sole antigen in both bands. Moreover, IgG from all of the SSc patients who recognized the 75- and/or 85-kDa bands bound to a full-length recombinant CENP-B protein as assessed by ELISA, whereas IgG from other SSc patients did not. The main target of anti-endothelial cell antibodies in patients with limited cutaneous SSc is the nuclear and ubiquitous protein CENP-B. [Copyright &y& Elsevier]

Objectives Displaying immunosuppressive and trophic properties, mesenchymal stem/stromal cells (MSC) are being evaluated as promising therapeutic options in a variety of autoimmune and degenerative diseases. Although benefits may be expected in systemic sclerosis (SSc), a rare autoimmune disease with fibrosis-related mortality, MSC have yet to be evaluated in this specific condition. While autologous approaches could be inappropriate because of functional alterations in MSC from patients, the objective of the present study was to evaluate allogeneic and xenogeneic MSC in the HOCl-induced model of diffuse SSc. We also questioned the source of human MSC and compared bone marrow- (hBM-MSC) and adipose-derived MSC (hASC). Methods HOCl-challenged BALB/c mice received intravenous injection of BM-MSC from syngeneic BALB/c or allogeneic C57BL/6 mice, and xenogeneic hBM-MSC or hASC (3 donors each). Skin thickness was measured during the experiment. At euthanasia, histology, immunostaining, collagen determination and RT-qPCR were performed in skin and lungs. Results Xenogeneic hBM-MSC were as effective as allogeneic or syngeneic BM-MSC in decreasing skin thickness, expression of Col1 , Col3 , α-Sma transcripts, and collagen content in skin and lungs. This anti-fibrotic effect was not associated with MSC migration to injured skin or with long-term MSC survival. Interestingly, compared with hBM-MSC, hASC were significantly more efficient in reducing skin fibrosis, which was related to a stronger reduction of TNFα , IL1 β, and enhanced ratio of Mmp1/Timp1 in skin and lung tissues. Conclusions Using primary cells isolated from 3 murine and 6 human individuals, this preclinical study demonstrated similar therapeutic effects using allogeneic or xenogeneic BM-MSC while ASC exerted potent anti-inflammatory and remodeling properties. This sets the proof-of-concept prompting to evaluate the therapeutic efficacy of allogeneic ASC in SSc patients. [ABSTRACT FROM AUTHOR]

Objectives To describe the pathophysiological mechanisms involving cytomegalovirus (CMV) primary infection and natural killer (NK) cell expansion in the development of localized scleroderma. Results A 43-year-old woman presented acute erythematous discoloration and skin thickening concerning face, neck, trunk, abdomen, and the four limbs, predominantly in proximal areas. Our case did not respond to systemic sclerosis criteria diagnosis. However, skin and muscle biopsy revealed early scleroderma associated with capillary thrombi, and tissue infiltration with NK cells (CD56+/Granzyme B). Scleroderma was attributed to CMV primary infection responsible for cytolytic hepatitis (7-fold over the limit) and circulating NK cell excess. After 6 months of prednisone and a 2-year follow-up, a complete resolution of symptoms was observed. Conclusion Our observation suggests a potential triggering role of CMV primary infection in the development of scleroderma. Histological features from our observation addresses the role of CMV and NK cells in the development of endothelial damage and fibrotic process. [ABSTRACT FROM AUTHOR]