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Le Touquet – Paris-Plage, France

Schuetz C.,University of Ulm | Neven B.,Unite dImmuno Hematologie | Neven B.,University of Paris Descartes | Dvorak C.C.,University of California at San Francisco | And 29 more authors.
Blood | Year: 2014

A subgroup of severe combined immunodeficiencies (SCID) is characterized by lack of T and B cells and is caused by defects in genes required for T- and B-cell receptor gene rearrangement. Several of these genes are also involved in nonhomologous end joining of DNA double-strand break repair, the largest subgroup consisting of patients with T-B-NK +SCID due to DCLRE1C/ARTEMIS defects. We postulated that in patients with ARTEMIS deficiency, early and late complications following hematopoietic cell transplantation might be more prominent compared with patients with T -B-NK+SCID caused by recombination activating gene 1/2 (RAG1/2) deficiencies. We analyzed 69 patients with ARTEMIS and 76 patients with RAG1/2 deficiencies who received transplants from either HLA-identical donors without conditioning or from HLA-nonidentical donors without or with conditioning. There was no difference in survival or in the incidence or severity of acute graft-versus-host disease regardless of exposure to alkylating agents. Secondary malignancies were not observed. Immune reconstitution was comparable in both groups, however, ARTEMIS-deficient patients had a significantly higher occurrence of infections in long-term follow-up. There is a highly significant association between poor growth in ARTEMIS deficiency and use of alkylating agents. Furthermore, abnormalities in dental development and endocrine late effects were associated with alkylation therapy in ARTEMIS deficiency. (Blood. 2014;123(2):281-289). © 2014 by The American Society of Hematology. Source

Fischer A.,French Institute of Health and Medical Research | Fischer A.,University of Paris Descartes | Picard C.,University of Paris Descartes | Picard C.,Center detude des deficits immunitaires | And 8 more authors.
Seminars in Immunopathology | Year: 2010

The protein tyrosine kinase ZAP70 became the subject of intense scrutiny in the early nineties, when ZAP70 mutations were characterized in several young patients presenting with severe T cell immunodeficiencies. The association of a lack of expression of ZAP70 with an immunodeficiency consisting in a markedly reduced T lymphocyte-mediated immunity highlighted the crucial role of this tyrosine kinase in T cell development and function. This discovery was soon accompanied by the characterization of the substrates of ZAP70 and the signalling cascades that depend on ZAP70 activity. These studies demonstrated that ZAP70 was indeed at the crossroad of several signalling pathways that control T lymphocyte development and function. Recently, a revival of interest for this protein came again from studies associating abnormal ZAP70 expression with pathological conditions. Some chronic lymphocytic leukemia B cells were shown to express ZAP70, and this expression was correlated with bad prognosis. Mouse models also revealed that partial defects in ZAP70 activity can be associated with autoimmunity. These last results suggested that ZAP70 is involved in the fine balance between immunity and tolerance. In this review, we will discuss the role of ZAP70 in T cell activation and focus on what we learnt from pathological conditions associated with defective expression or activity of the ZAP70 kinase. © 2010 Springer-Verlag. Source

Magerus-Chatinet A.,French Institute of Health and Medical Research | Magerus-Chatinet A.,University of Paris Descartes | Stolzenberg M.-C.,French Institute of Health and Medical Research | Stolzenberg M.-C.,University of Paris Descartes | And 18 more authors.
Journal of Allergy and Clinical Immunology | Year: 2013

Background: Autoimmune lymphoproliferative syndrome (ALPS) is characterized by chronic nonmalignant lymphoproliferation, accumulation of double-negative T cells, hypergammaglobulinemia G and A, and autoimmune cytopenia. Objectives: Although mostly associated with FAS mutations, different genetic defects leading to impaired apoptosis have been described in patients with ALPS, including the FAS ligand gene (FASLG) in rare cases. Here we report on the first case of complete FAS ligand deficiency caused by a homozygous null mutant. Methods: Double-negative T-cell counts and plasma IL-10 and FAS ligand concentrations were determined as ALPS markers. The FASLG gene was sequenced, and its expression was analyzed by means of Western blotting. FAS ligand function was assessed based on reactivation-induced cell death. Results: We describe a patient born to consanguineous parents who presented with a severe form of ALPS caused by FASLG deficiency. Although the clinical presentation was compatible with a homozygous FAS mutation, FAS-induced apoptosis was normal, and plasma FAS ligand levels were not detectable. This patient carries a homozygous, germline, single-base-pair deletion in FASLG exon 1, leading to a premature stop codon (F87fs x95) and a complete defect in FASLG expression. The healthy parents were each heterozygous for the mutation, confirming its recessive trait. Conclusion: FAS ligand deficiency should be screened in patients presenting with ALPS features but lacking the usual markers, including plasma soluble FAS ligand and an in vitro apoptotic defect. An activation-induced cell death test could help in discrimination. © 2012 American Academy of Allergy, Asthma & Immunology. Source

De Saint Basile G.,French Institute of Health and Medical Research | De Saint Basile G.,University of Paris Descartes | De Saint Basile G.,Center detude des deficits immunitaires | Menasche G.,French Institute of Health and Medical Research | And 3 more authors.
Nature Reviews Immunology | Year: 2010

Cytotoxic T cells and natural killer cells are crucial for immune surveillance against virus-infected cells and tumour cells. Molecular studies of individuals with inherited defects that impair lymphocyte cytotoxic function have also highlighted the importance of cytotoxicity in the regulation and termination of immune responses. As discussed in this Review, characterization of these defects has contributed to our understanding of the key steps that are required for the maturation of cytotoxic granules and the secretion of their contents at the immunological synapse during target cell killing. This has revealed a marked similarity between cytotoxic granule exocytosis at the immunological synapse and synaptic vesicle exocytosis at the neurological synapse. We explore the possibility that comparison of these two kinetically and spatially regulated secretory pathways will provide clues to uncover additional effectors that regulate the cytotoxic function of lymphocytes. © 2010 Macmillan Publishers Limited. All rights reserved. Source

Al-Herz W.,Kuwait University | Al-Herz W.,Allergy and Clinical Immunology Unit | Bousfiha A.,Hassan II University | Casanova J.-L.,Rockefeller University | And 20 more authors.
Frontiers in Immunology | Year: 2014

We report the updated classification of primary immunodeficiencies (PIDs) compiled by the Expert Committee of the International Union of Immunological Societies. In comparison to the previous version, more than 30 new gene defects are reported in this updated version. In addition, we have added a table of acquired defects that are phenocopies of PIDs. For each disorder, the key clinical and laboratory features are provided. This classification is the most up-to-date catalog of all known PIDs and acts as a current reference of the knowledge of these conditions and is an important aid for the molecular diagnosis of patients with these rare diseases. © 2014 Al-Herz, Bousfiha, Casanova, Chatila, Conley, Cunningham-Rundles, Etzioni, Franco, Gaspar, Holland, Klein, Nonoyama, Ochs, Oksenhendler, Picard, Puck, Sullivan and Tang. Source

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