The Ets-1 transcription factor controls the development and function of natural regulatory T cells

Regulatory T cells (T reg cells) constitute a population of CD4+ T cells that limits immune responses. The transcription factor Foxp3 is important for determining the development and function of T reg cells; however, the molecular mechanisms that trigger and maintain its expression remain incompletely understood. In this study, we show that mice deficient for the Ets-1 transcription factor (Ets-1−/−) developed T cell–mediated splenomegaly and systemic autoimmunity that can be blocked by functional wild-type T reg cells. Spleens of Ets-1−/− mice contained mostly activated T cells, including Th2-polarized CD4+ cells and had reduced percentages of T reg cells. Splenic and thymic Ets-1−/− T reg cells expressed low levels of Foxp3 and displayed the CD103 marker that characterizes antigen-experienced T reg cells. Thymic development of Ets-1−/− T reg cells appeared intrinsically altered as Foxp3-expressing cells differentiate poorly in mixed fetal liver reconstituted chimera and fetal thymic organ culture. Ets-1−/− T reg cells showed decreased in vitro suppression activity and did not protect Rag2−/− hosts from naive T cell–induced inflammatory bowel disease. Furthermore, in T reg cells, Ets-1 interacted with the Foxp3 intronic enhancer and was required for demethylation of this regulatory sequence. These data demonstrate that Ets-1 is required for the development of natural T reg cells and suggest a role for this transcription factor in the regulation of Foxp3 expression

Premises of social cognition: Newborns are sensitive to a direct versus a faraway gaze

International audiencePrevious studies evidenced that already from birth, newborns can perceive differences between a direct versus an averted gaze in faces both presented in static and interactive situations. It has been hypothesized that this early sensitivity would rely on modifications of the location of the iris (i.e. the darker part of the eye) in the sclera (i.e. the white part), or that it would be an outcome of newborns’ preference for configurations of faces with the eye region being more contrasted. One question still remains: What happens when the position of the iris is not modified in the sclera, but the look is ‘faraway’, that is when the gaze is toward the newborns’ face but above his or her own eyes? In the present study, we tested the influence of a direct versus a faraway gaze (i.e., two gazes that only differed slightly in the position of the iris on the vertical axis and not on the horizontal axis) on newborns’ face recognition. The procedure was identical to that used in previous studies: using a familiarization-test procedure, we familiarized two groups of newborns (N = 32) with videos of different talking faces that were presented with either a direct or a faraway gaze. Newborns were then tested with photographs of the face seen previously and of a new one. Results evidenced that newborns looked longer at the familiar face, but only in the direct gaze condition. These results suggest that, already from birth, infants can perceive slight differences of gazes when someone is addressing to them

L'imagerie par bioluminescence pour visualiser la progression tumorale et la métastase chez le petit animal

De nouveaux modèles animaux sont nécessaires pour améliorer la détection précoce et le suivi de la dissémination métastatique afin de développer des thérapies efficaces contre les formes les plus agressives de cancer. Ce chapitre détaille les avantages et les limites de l'utilisation de l'imagerie par bioluminescence (IB). Bien que l'IB permette de détecter en temps réel avec une grande sensibilité et de façon non invasive des lésions tumorales in vivo, cette approche souffre notamment d'une résolution anatomique relativement faible et d'une atténuation du signal par le tissu traversé

Phase II study of vinorelbine in patients with androgen-independent prostate cancer.

PURPOSE: To evaluate the efficacy and toxicity of vinorelbine in a phase II study in patients with progressive metastatic androgen-independent prostate cancer. PATIENTS AND METHODS: Forty-seven men with progressive metastatic prostate cancer refractory to first-line or second-line hormonal therapy were treated with vinorelbine, a semisynthetic vinca-alkaloid. Vinorelbine was given, on an outpatient schedule, at 25 mg/m2 weekly for at least eight weeks or until progression or excessive toxicity. RESULTS: Forty-seven patients were included in the study, 33 being evaluable for tumour response, 36 for response to PSA, 21 for clinical benefit and 45 for toxicity. Median actual weekly dose was 19 mg/m2 (range 12.0-26.2 mg/m2). Six of thirty-six patients (17%) demonstrated a biologic response with a 50% or more decline in serum PSA on two consecutive measurements taken at least two weeks apart. The median duration of biologic response was 2.7 months. Two of three patients with measurable disease obtained an objective response but remained unconfirmed. No change disease was reported in 23 patients (49%). On entry into the study, 30 patients had symptomatic bone pain and required narcotic or non-narcotic analgesics. Clinical benefit from vinorelbine was achieved in 15 patients out of 21 (32% of the intent to treat analysis population and 71% of the assessable patients). Due to the low number of questionnaires (QLQ-C30) filled in, it was insufficient to allow any statistical analysis. The median survival was 10.2 months. Toxicity was mainly haematologic with 51% of patients experiencing grade 3 or 4 granulocytopenia. Three patients developed deep vein thrombosis. Non-haematologic toxicity, mainly nausea and neurotoxicity, was mild. CONCLUSION: The administration of weekly vinorelbine appears to be a safe treatment for those patients with androgen-independent prostate cancer and poor prognosis features who require chemotherapy. These results provide data for future investigation of vinorelbine in combination regimens.Clinical TrialClinical Trial, Phase IIComparative StudyJournal ArticleMulticenter StudyRandomized Controlled TrialResearch Support, Non-U.S. Gov'tinfo:eu-repo/semantics/publishe

DNA-mediated adjuvant immunotherapy extends survival in two different mouse models of myeloid malignancies

We have previously shown that a specific promyelocytic leukemia-retinoic acid receptor alpha (PML-RARA) DNA vaccine combined with all-trans retinoic acid (ATRA) increases the number of long term survivors with enhanced immune responses in a mouse model of acute promyelocytic leukemia (APL). This study reports the efficacy of a non-specific DNA vaccine, pVAX14Flipper (pVAX14), in both APL and high risk myelodysplastic syndrome (HR-MDS) models. PVAX14 is comprised of novel immunogenic DNA sequences inserted into the pVAX1 therapeutic plasmid. APL mice treated with pVAX14 combined with ATRA had increased survival comparable to that obtained with a specific PML-RARA vaccine. Moreover, the survival advantage correlated with decreased PML-RARA transcript levels and increase in anti-RARA antibody production. In HR-MDS mice, pVAX14 significantly improved survival and reduced biomarkers of leukemic transformation such as phosphorylated mitogen-activated protein/extracellular signal-regulated kinase kinase (MEK) 1. In both preclinical models, pVAX14 vaccine significantly increased interferon gamma (IFNγ) production, memory T-cells (memT), reduced the number of colony forming units (CFU) and increased expression of the adapter molecule signalling to NF-κB, MyD88. These results demonstrate the adjuvant properties of pVAX14 providing thus new approaches to improve clinical outcome in two different models of myeloid malignancies, which may have potential for a broader applicability in other cancers

p16INK4A tumor suppressor gene expression and CD3ϵ deficiency but not pre-TCR deficiency inhibit TAL1-linked T-lineage leukemogenesis

Inactivation of the CDKN2 genes that encode the p16INK4A and p14ARF proteins occurs in the majority of human T-cell acute lymphoblastic leukemias (T-ALLs). Ectopic expression of TAL1 and LMO1 genes is linked to the development of T-ALL in humans. In TAL1xLMO1 mice, leukemia develops in 100% of mice at 5 months. To identify the molecular events crucial to leukemic transformation, we produced several mouse models. We report here that expression of P16INK4A in developing TAL1xLMO1 thymocytes blocks leukemogenesis in the majority of the mice, and the leukemias that eventually develop show P16INK4A loss of expression. Events related to the T-cell receptor β selection process are thought to be important for leukemic transformation. We show here that the absence of the pTα chain only slightly delays the appearance of TAL1xLMO1-induced T-ALL, which indicates a minor role of the pTα chain. We also show that the CD3ϵ-mediated signal transduction pathway is essential for this transformation process, since the TAL1xLMO1xCD3ϵ-deficient mice do not develop T-ALL for up to 1 year

Effect of anakinra versus usual care in adults in hospital with COVID-19 and mild-to-moderate pneumonia (CORIMUNO-ANA-1): a randomised controlled trial

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Effect of Tocilizumab vs Usual Care in Adults Hospitalized With COVID-19 and Moderate or Severe Pneumonia

International audienceImportance Severe pneumonia with hyperinflammation and elevated interleukin-6 is a common presentation of coronavirus disease 2019 (COVID-19).Objective To determine whether tocilizumab (TCZ) improves outcomes of patients hospitalized with moderate-to-severe COVID-19 pneumonia.Design, Setting, and Particpants This cohort-embedded, investigator-initiated, multicenter, open-label, bayesian randomized clinical trial investigating patients with COVID-19 and moderate or severe pneumonia requiring at least 3 L/min of oxygen but without ventilation or admission to the intensive care unit was conducted between March 31, 2020, to April 18, 2020, with follow-up through 28 days. Patients were recruited from 9 university hospitals in France. Analyses were performed on an intention-to-treat basis with no correction for multiplicity for secondary outcomes.Interventions Patients were randomly assigned to receive TCZ, 8 mg/kg, intravenously plus usual care on day 1 and on day 3 if clinically indicated (TCZ group) or to receive usual care alone (UC group). Usual care included antibiotic agents, antiviral agents, corticosteroids, vasopressor support, and anticoagulants.Main Outcomes and Measures Primary outcomes were scores higher than 5 on the World Health Organization 10-point Clinical Progression Scale (WHO-CPS) on day 4 and survival without need of ventilation (including noninvasive ventilation) at day 14. Secondary outcomes were clinical status assessed with the WHO-CPS scores at day 7 and day 14, overall survival, time to discharge, time to oxygen supply independency, biological factors such as C-reactive protein level, and adverse events.Results Of 131 patients, 64 patients were randomly assigned to the TCZ group and 67 to UC group; 1 patient in the TCZ group withdrew consent and was not included in the analysis. Of the 130 patients, 42 were women (32%), and median (interquartile range) age was 64 (57.1-74.3) years. In the TCZ group, 12 patients had a WHO-CPS score greater than 5 at day 4 vs 19 in the UC group (median posterior absolute risk difference [ARD] −9.0%; 90% credible interval [CrI], −21.0 to 3.1), with a posterior probability of negative ARD of 89.0% not achieving the 95% predefined efficacy threshold. At day 14, 12% (95% CI −28% to 4%) fewer patients needed noninvasive ventilation (NIV) or mechanical ventilation (MV) or died in the TCZ group than in the UC group (24% vs 36%, median posterior hazard ratio [HR] 0.58; 90% CrI, 0.33-1.00), with a posterior probability of HR less than 1 of 95.0%, achieving the predefined efficacy threshold. The HR for MV or death was 0.58 (90% CrI, 0.30 to 1.09). At day 28, 7 patients had died in the TCZ group and 8 in the UC group (adjusted HR, 0.92; 95% CI 0.33-2.53). Serious adverse events occurred in 20 (32%) patients in the TCZ group and 29 (43%) in the UC group (P = .21).Conclusions and Relevance In this randomized clinical trial of patients with COVID-19 and pneumonia requiring oxygen support but not admitted to the intensive care unit, TCZ did not reduce WHO-CPS scores lower than 5 at day 4 but might have reduced the risk of NIV, MV, or death by day 14. No difference on day 28 mortality was found. Further studies are necessary for confirming these preliminary results.Trial Registration ClinicalTrials.gov Identifier: NCT0433180