Publications by authors named "Christophe Baron"

Introduction: Hepatitis E virus (HEV) can cause chronic infection (≥3 months) and cirrhosis in immunocompromised patients, especially kidney transplant recipients. Low alanine aminotransferase (ALT) levels and high HEV intrahost diversity have previously been associated with evolution toward chronicity in these patients. We hypothesized that additional clinical and viral factors could be associated with the risk of chronic HEV infection.

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Recent evidence showed that in response to elevated sodium dietary intakes, many body tissues retain Na ions for long periods of time and can reach concentrations up to 200 mM. This could modulate the immune system and be responsible for several diseases. However, studies brought contrasted results and the effects of external sodium on human dendritic cell (DC) responses to danger signals remain largely unknown.

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Article Synopsis
  • Basiliximab is a medicine used to stop kidney transplant rejection, and this study looked at how it works in the body.
  • Researchers reanalyzed data from 16 kidney transplant patients who received different doses of basiliximab.
  • They found that men had higher levels of the medicine and that another drug, cyclosporine, seemed to lower the effects of basiliximab, suggesting that dosing could be improved.
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The gene, coding for the Naβ4 subunit of voltage-gated sodium channels, was recently found to be expressed in normal epithelial cells and down-regulated in several cancers. However, its function in normal epithelial cells has not been characterized. In this study, we demonstrated that reducing Naβ4 expression in MCF10A non-cancer mammary epithelial cells generated important morphological changes observed both in two-dimensional cultures and in three-dimensional cysts.

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Implantable cardioverter-defibrillators (ICD) are meant to fight life-threatening ventricular arrhythmias and reduce overall mortality. Ironically, life-saving shocks themselves have been shown to be independently associated with an increased mortality. We sought to identify myocardial changes at the protein level immediately after ICD electrical shocks using a proteomic approach.

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The acquisition of invasive capacities by carcinoma cells, i.e. their ability to migrate through and to remodel extracellular matrices, is a determinant process leading to their dissemination and to the development of metastases.

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Sterile inflammation is a key determinant of myocardial reperfusion injuries. It participates in infarct size determination in acute myocardial infarction and graft rejection following heart transplantation. We previously showed that P2Y11 exerted an immunosuppressive role in human dendritic cells, modulated cardiofibroblasts' response to ischemia/reperfusion in vitro and delayed graft rejection in an allogeneic heterotopic heart transplantation model.

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Background: Renal resistive index (RI) predicts mortality in renal transplant recipients, but we do not know whether this is true in diabetic patients. The objective of this study was to analyse the long-term predictive value of RI for death with a functioning graft (DWFG) in renal transplant recipients with or without pre-transplant diabetes.

Methods: We conducted a retrospective study in 1800 renal transplant recipients between 1985 and 2017 who were followed for up to 30 years (total observation period: 14 202 patient years).

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Depleting induction therapy is recommended in sensitized kidney transplant recipients (KTRs), though the detrimental effect of nondonor-specific anti-HLA antibodies is not undeniable. We compared the efficacy and safety of basiliximab and rabbit anti-thymocyte globulin (rATG) in sensitized KTRs without pre-existing donor-specific antibodies (DSAs). This monocentric retrospective study involved all sensitized KTR adults without pre-existing DSAs (n = 218) who underwent transplantation after June 2007.

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High renal resistive index (RI) is observed in diabetes and is associated with poor patient survival, but whether it is primarily due to renal vascular resistance or systemic vascular alterations is unclear. The respective impact of kidney transplant from diabetic donors or to diabetic recipients on RI would shed some light on this issue. The objective of the study was to analyze the impact of donor and recipient diabetes on RI in order to understand the respective impact of the kidney and the vascular environment.

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Cardiac fibroblasts are important regulators of myocardial structure and function. Their implications in pathological processes such as Ischemia/Reperfusion are well characterized. Cardiac fibroblasts respond to stress by excessive proliferation and secretion of pro-inflammatory cytokines and other factors, e.

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We aimed to determine the role of cytomegalovirus (CMV)-infected donor cells in the development of a CMV-specific immune response in kidney transplant recipients. We assessed the CMV pp65-specific immune response by using interferon-ɣ ELISPOT and dextramers in peripheral blood mononuclear cells from 115 recipients (D+R- 31, D+R + 44, D-R + 40) late after transplantation (mean 59 ± 42 months). Receiving a kidney from a D+ donor resulted in a higher number of IFN-ɣ-producing anti-CMV T cells (P = .

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Background: Cytomegalovirus (CMV) has a role in chronic rejection and graft loss in kidney transplant (KTx) and lung transplant (LTx) recipients. In addition, donor CMV seropositivity is an independent risk factor for renal graft loss. The anti-CMV response might modulate this risk.

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Background: An efficient strategy for programming dendritic cells (DCs) for cancer immunotherapy is the optimization of their maturation so that they can efficiently stimulate cancer-specific T cell responses. Interleukin (IL)-4 has appeared as an essential cytokine, widely used in vitro with granulocyte macrophage-colony stimulating factor (GM-CSF) to differentiate monocytes into immature DCs (iDC) and to prevent macrophage formation. Conflicting data have been published regarding the effect of IL-4 on functional DC maturation.

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High concentrations of extracellular ATP (eATP) resulting from cell damage may be found during an ischemia/reperfusion (I/R) episode at the site of injury. eATP activates purinergic receptors in dendritic cells (DCs) and may inhibit inflammation. This immunosuppressive activity could be of interest in the field of I/R, which is an inflammatory condition involved in myocardial infarction, stroke, and solid organ transplantation.

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Human dendritic cells (hDCs) produce IL-2 and express IL-2R α-chain (CD25), but the role of IL-2 in DC functions is not well defined. A recent study suggested that the main function of CD25 on hDCs was to transpresent IL-2 to activate T lymphocytes. Our results demonstrate the expression of the three chains of the IL-2R on hDCs and that IL-2 induces STAT5 phosphorylation.

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To describe long-term CD4+ T-cell reconstitution after rabbit antithymocyte globulin (rATG) treatment and identify predictive factors following kidney transplantation. A single-center retrospective study analyzed lymphocyte subsets in rATG-treated kidney transplant recipients (1986-2009). 589 patients were analyzed (maximum follow-up 21 years).

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Regulatory T cells (Treg) play a crucial role in controlling immunity and transplant rejection. Two main groups of Treg have been described: antigen-induced Treg (iTreg) and natural Treg (nTreg). The ways to induce and the mechanisms of action of Treg subsets remained ill defined, particularly for their effects on CD8(+) T cells.

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Rabbit antithymocyte globulin (rATG; Thymoglobulin(®)) is currently used to prevent acute rejection in kidney transplantation. The dose and regimen of rATG have not been optimized. Moreover, the impact of different treatment regimens on T-cell phenotype reconstitution remains unknown.

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A large body of evidence has been accumulated from experimental models in the past decade to support the critical role of Foxp3-expressing regulatory T cells (Tregs) in the suppression of alloimmune responses. This has prompted transplant clinicians to investigate whether Foxp3 analysis might be used as an immunodiagnostic tool for better assessment of the significance of graft infiltrate and to predict its impact on graft outcome. However, conflicting results have emerged from these studies and may have generated more confusion than clarification.

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The high frequency of allogeneic reactive CD8(+) T cells in human and their resistance to immunosuppression might be one of the reasons why successful tolerance-inducing strategies in rodents have failed in primates. Studies on the requirement for T-helper cells in priming CD8(+) T-cell responses have led to disparate findings. Recent studies have reported CD8(+)-mediated allograft rejection independently of T-helper cells; however, the mechanisms that govern the activation of these T cells are far from being elucidated.

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Purpose Of The Review: Indirect effects of cytomegalovirus (CMV) in transplantation are of three types: increase in systemic immunosuppression, increased risk of malignancy (especially Epstein-Barr virus-related B-cell lymphoproliferative disease), and the possible contribution to allograft injury. Despite modern and potent antiviral drugs, the real impact of CMV in transplantation, especially kidney transplantation, remains a challenge because many confounding factors arise when analyzing this question.This review will fuel the discussion and review some of the recent data.

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Mycophenolic acid (MPA) is an immunosuppressive drug which induces resistance to several maturation signals in human dendritic cells (DC) by unknown mechanisms. As mitogen-activated protein kinases (MAPK) are involved in the maturation process, we studied whether MPA affected p38MAPK and extracellular signal-regulated kinase (ERK1/2) in human DC. We first showed that MPA reduced TNFalpha-induced phenotype maturation, whereas it had no effect after LPS activation, suggesting that MPA preferentially affects the signaling pathway used by TNFalpha.

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New-onset diabetes after transplantation (NODAT) is a serious and frequent complication in transplant recipients. Whether NODAT shares the same susceptibility genes as type 2 diabetes is unknown. In this multicenter study, we genotyped 1076 white patients without diabetes at transplantation for 11 polymorphisms that associate with type 2 diabetes.

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Background: Cytomegalovirus (CMV) infection is the most frequent infectious disease following organ transplantation. Strategies to prevent this infection remain a matter for debate, and discovering genetic risk factors might assist in adapting preventive strategies. By inhibiting IFNgamma production, programmed death 1 (PD-1) has a crucial role in anti-CMV immune response.

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