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Alloimmunité - Auto-immunité - Transplantation

A2T

Tutelles >

Université Paris Diderot

UFR de rattachement >

Institut Universitaire Hématologie (IUH)

Label unité >

UMRS

Partenaires >

INSERM

Présentation

Equipes de recherche

Equipe 1 - Différentiation lymphocytaire et homéostasie dans l’allo et l’autoimmunité

Antoine Toubert

Groupe 1 – Matthieu Allez – Maladies inflammatoires du tube digestif

Groupe 2 – Ryad Tamouza - Immunogénétique

Equipe 2 - Régulation de la réponse immunitaire allogénique lors d’une transplantation rénale

Nuala Mooney

Equipe 3 - Greffes de cellules souches hématopoietiques

Gérard Socié

Equipe 4 - Physique du cytosquelette et de la morphogenèse

Manuel Théry

Equipe 5 - NK et Cancer

Anne Caignard

Equipe 6 - INKT pathologies

Kamel Benlagha

[inserm-01624830] Molecular and Functional Characterization of Lymphoid Progenitor Subsets Reveals a Bipartite Architecture of Human Lymphopoiesis.

Date: 26 Oct 2017 - 18:45

Desc: The classical model of hematopoiesis established in the mouse postulates that lymphoid cells originate from a founder population of common lymphoid progenitors. Here, using a modeling approach in humanized mice, we showed that human lymphoid development stemmed from distinct populations of CD127- and CD127+ early lymphoid progenitors (ELPs). Combining molecular analyses with in vitro and in vivo functional assays, we demonstrated that CD127- and CD127+ ELPs emerged independently from lympho-mono-dendritic progenitors, responded differently to Notch1 signals, underwent divergent modes of lineage restriction, and displayed both common and specific differentiation potentials. Whereas CD127- ELPs comprised precursors of T cells, marginal zone B cells, and natural killer (NK) and innate lymphoid cells (ILCs), CD127+ ELPs supported production of all NK cell, ILC, and B cell populations but lacked T potential. On the basis of these results, we propose a "two-family" model of human lymphoid development that differs from the prevailing model of hematopoiesis.

[inserm-04029164] Expression of CD94 by ex vivo -differentiated NK cells correlates with the in vitro and in vivo acquisition of cytotoxic features

Date: 14 Mar 2023 - 18:16

Desc: The administration of ex vivo-expanded Natural Killer (NK) cells in leukemia therapy is still challenging, in part due to the difficulty to generate in sufficient quantities fully mature and functional NK cells and Identification of surface markers indicative of NK maturation and functionality is therefore needed. Here, based on the analysis of surface receptors of ex vivo-expanded NK cells, we identified CD94 as a surface marker correlating with high lytic potential against leukemic cell lines and immunological synapse formation. CD94-positive ex vivo-expanded NK cells displayed higher expression of NKG2 receptors and the adhesion molecule LFA-1, as compared with their CD94-negative counterparts. We also tested the in vivo anti-leukemic capacity of ex vivo-expanded NK cells against patient-derived acute myeloid leukemia cells. Although no anti-leukemic effect was detected, we noticed that only CD94-positive ex vivoexpanded NK cells were detected in leukemic mice at the end of the 2-week treatment. Moreover, flow cytometry analysis showed a subpopulation harboring CD94 (NK) and CD34 (leukemic cells) double staining, indicative of conjugate formation. Therefore surface expression of CD94 on ex vivo-differentiated NK cells emerged as an indicator of in vitro and in vivo killer cell functionality.

[hal-01789566] NKp46 expression on NK cells as a prognostic and predictive biomarker for response to allo-SCT in patients with AML

Date: 11 May 2018 - 11:03

Desc: NKp46 is a major determinant of natural killer (NK) cell function and it is implicated in tumor immune surveillance in acute myeloid leukemia (AML). The purpose of this study was to investigate the prognostic significance of NKp46 expression in an independent cohort of patients with AML, and to investigate the impact of NKp46 on clinical outcome after allogeneic stem cell transplantation (allo-SCT). NKp46 expression was assessed at diagnosis on NK cells by flow cytometry (N = 180 patients). Clinical outcome was evaluated with regard to NKp46 expression. Patients with NKp46high phenotype at diagnosis had better progression-free survival (PFS) and overall survival (OS) than patients with NKp46low phenotype (74.3% vs. 46.6%, p = 0.014; 82.6% vs. 57.1%, p = 0.010, respectively). In multivariate analysis, high NKp46 was an independent factor for improved OS (HR = 0.409, p = 0.010) and PFS (HR = 0.335, p = 0.011). Subgroup analysis revealed that allo-SCT had a favorable impact on PFS in patients with NKp46high phenotype (p = 0.025). By contrast, allo-SCT did not impact PFS in patients with low NKp46 expression (p = 0.303). In conclusion, we validate the prognostic value of NKp46 expression at diagnosis in AML. However, the prognostic value of NKp46 expression is limited to patients treated with allo-SCT, thus suggesting that NKp46 status may be predictive for allo-SCT responsiveness.

[hal-01765085] NKp30 isoforms and NKp30 ligands are predictive biomarkers of response to imatinib mesylate in metastatic GIST patients

Date: 12 Apr 2018 - 16:38

Desc: Despite effective targeted therapy acting on KIT and PDGFRA tyrosine kinases, gastrointestinal stromal tumors (GIST) escape treatment by acquiring mutations conveying resistance to imatinib mesylate (IM). Following the identification of NKp30-based immunosurveillance of GIST and the off-target effects of IM on NK cell functions, we investigated the predictive value of NKp30 isoforms and NKp30 soluble ligands in blood for the clinical response to IM. The relative expression and the proportions of NKp30 isoforms markedly impacted both event-free and overall survival, in two independent cohorts of metastatic GIST. Phenotypes based on disbalanced NKp30B/NKp30C ratio (Delta BClow) and low expression levels of NKp30A were identified in one third of patients with dismal prognosis across molecular subtypes. This Delta BClow blood phenotype was associated with a pro-inflammatory and immunosuppressive tumor microenvironment. In addition, detectable levels of the NKp30 ligand sB7-H6 predicted a worse prognosis in metastatic GIST. Soluble BAG6, an alternate ligand for NKp30 was associated with low NKp30 transcription and had additional predictive value in GIST patients with high NKp30 expression. Such GIST microenvironments could be rescued by therapy based on rIFN-alpha and anti-TRAIL mAb which reinstated innate immunity.