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Ce travail a permis d’établir un mode opératoire simple pour évaluer la quantité de déchets de tonte d’une variété de gazon dans le but d’intégrer ce caractère dans les études VATE menées dans le cadre de l’inscription au catalogue officiel français. L’étude a porté sur 18 variétés issues de 7 espèces de gazon fréquemment utilisées. L’ensemble de ces variétés a été testé dans 4 essais au champ conduits dans des lieux différents.[br/] Les résultats de cette expérimentation ont fait l’objet d’analyses statistiques intégrant différents caractères (hauteur de pousse, densité du gazon, finesse) et différents facteurs (lieux d’expérimentation, espèce) qui ont été mis en relation avec le poids de déchet de tonte des variétés.[br/] Des analyses de données simples et multiples basées sur l’ACP ont été réalisées avec le logiciel R et ont permis de préciser l’influence des facteurs d’intérêts (lieu, espèce), ainsi que les liaisons entre caractères qui pouvaient être exploitées dans une étape de modélisation. Des procédures de sélection de variables (de type ascendante-descendante ou encore utilisant la régression PLS) ont permis d’identifier les facteurs et les variables les plus explicatives du poids de déchet de tonte.[br/] Ce dernier a été modélisé grâce à une analyse de covariance, réalisée espèce par espèce, intégrant le facteur lieu et la hauteur de pousse estimée par une notation visuelle utilisant une échelle de 1 à 9. Un résultat important est que, pour une espèce donnée, la pente de la hauteur de pousse dans le modèle n’est pas significativement différente d’un lieu à l’autre. [br/] A la suite de cette étude, la production de déchets de tonte est évaluée en routine et fait partie des caractères du protocole de Valeur Agronomique, Technologique et Environnementale des variétés de gazon., This work aimed to determine a simple way to estimate the amount of grass clippings of a variety in order to take this character into account in the VCUS studies which lead to the registration in the official French catalog. The study dealt with 18 varieties from 7 commonly used species. These varieties were tested in 4 field trials conducted in different locations.[br/] The results of this field experimentation were subjected to statistical analyses based on different characters (height, density, fineness of leaves) and on different parameters (testing grounds, species) which were related to the amount of clipping.[br/] Simple and multiple factorial analyses inspired from PCA were performed with the R software. They made it possible to determine influence of location and species factors, and showed the correlations which could be exploited in a further modeling step. Some selection procedures (stepwise procedure based on AIC, or PLS regression) were used to identify factors and variables that were the most relevant to model the amount of clipping.[br/] The latter was modeled with an analysis of covariance, performed for each species, and dealing with the location factor and the height growth characteristics, assessed on a 1 to 9 scale. One important result was that the slope of the height growth term in the model was the same for each location.[br/] The amount of clipping is now routinely evaluated in the VCUS studies and is part of the VCUS protocol for turf grass varieties.

International audience; Wiskott–Aldrich syndrome (WAS) is an immune deficiency with thrombopenia resulting from mutations in the WASP gene. This gene normally encodes the Wiskott–Aldrich syndrome protein (WASP), a major cytoskeletal regulator expressed in hematopoietic cells. Gene therapy is a promising option for the treatment of WAS, requiring that clinically applicable WASP gene transfer vectors demonstrate efficacy in preclinical studies. Here, we describe a self-inactivating HIV-1-derived lentiviral vector encoding human WASP and show that it effectively transduced bone marrow progenitor cells of WASP knockout (WKO) mice. Transplantation of these transduced cells into lethally irradiated WKO recipients led to stable expression of WASP and correction of immune, inflammatory and cytoskeletal defects. Splenic T-cell proliferation was restored, podosomes were reinstated on bone-marrow-derived dendritic cells and colon inflammation was reduced. This shows for the first time (a) that cytoskeletal defects can be corrected in WKO mice, (b) that human WASP is biologically active in mice and (c) that a lentiviral vector is effective to express human WASP in vivo over several months. These data support further development of such lentiviral vectors for the gene therapy of WAS.

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In order to avoid modified radical mastectomy, a neoadjuvant approach was adopted in our institute for operable bulky breast cancers. From January, 1982, to December, 1995, 288 patients received primary chemotherapy with 3 different regimens (all doses mg/m2): (1) AVCF/AVCFM, 167 patients (adriamycin 30, vincristine 1 d1, cyclophosphamide 300, fluorouracil 400 d2-d5 and methotrexate 20 d2 and d4, every 28 days); (2) NEM, 78 patients (vinorelbine 25, epirubicin 35, methotrexate 20 d1 and d8, every 28 days); and (3) TNCF, 43 patients (THP-adria 20, d1-d3, vinorelbine 25 d1 and d4, cyclophosphamide 300, fluorouracil 400 d1-d4, every 21 days). Evaluation of the response comprised 3 methods: clinical (C), echographic (E), mammographic (M). The overall objective response rate (C: 63/90/93; E: 49/61/85; M: 53/65/83%) is higher with regimens (2) and (3). The complete response rate was increased 2-fold with TNCF but the hematologic toxicity was very superior with this combination. Patients were all operated for (2) and (3), only several for (1), and the breast conservation rate (68/83/79%) was quite similar in the 3 regimens. The pathological complete response rate reached 23% with TNCF. However the impact on patient survival has to be confirmed.

Assess the importance of systematic surgical exploration of the tumor focus in case of complete clinical response to neoadjuvant chemotherapy for operable breast cancer.Between 1985 and 1997, first intention chemotherapy (4 to 6 cures) was given to 433 breast cancer patients with resectable tumors measuringor = 3 cm but who required mammectomy. Complete clinical response was observed in 112 patients (26%); 31 of them had normal mammography and ultrasound examinations (7%). Local treatment in this favorable context varied: 82 patients underwent surgery (71 conservative procedures, 11 radical procedures) and 30 patients received radiation therapy alone.Complete histological response was obtained in 22 cases accounting for 6% of the entire series, 27% of the complete clinical responses, and 45% of the complete clinical and imaging responses. The incidence of local recurrence at a mean 107 month follow-up was compared between patients given complementary surgical or radiation therapy after complete clinical response. Recurrence was observed in 10 of the 82 operated patients versus 8 of the 30 nonoperated patients (12% versus 27%, NS).Complete clinical response after neoadjuvant chemotherapy does not rule out the need for surgical resection of the tumor focus because the risk of neoplastic reliquats remains high (3 out of 4 cases) and because the surgical specimen provides important histological information for prognosis (in vivo chemosensitivity test). lumpectomy also contributes to reducing the risk of local recurrence.

National audience

International audience; From the perspective of a pilot clinical gene therapy trial for Wiskott-Aldrich syndrome (WAS), we implemented a process to produce a lentiviral vector under good manufacturing practices (GMP). The process is based on the transient transfection of 293T cells in Cell Factory stacks, scaled up to harvest 50 liters of viral stock per batch, followed by purification of the vesicular stomatitis virus glycoprotein-pseudotyped particles through several membrane-based and chromatographic steps. The process leads to a 200-fold volume concentration and an approximately 3-log reduction in protein and DNA contaminants. An average yield of 13% of infectious particles was obtained in six full-scale preparations. The final product contained low levels of contaminants such as simian virus 40 large T antigen or E1A sequences originating from producer cells. Titers as high as 2 x 10(9) infectious particles per milliliter were obtained, generating up to 6 x 10(11) infectious particles per batch. The purified WAS vector was biologically active, efficiently expressing the genetic insert in WAS protein-deficient B cell lines and transducing CD34(+) cells. The vector introduced 0.3-1 vector copy per cell on average in CD34(+) cells when used at the concentration of 10(8) infectious particles per milliliter, which is comparable to preclinical preparations. There was no evidence of cellular toxicity. These results show the implementation of large-scale GMP production, purification, and control of advanced HIV-1-derived lentiviral technology. Results obtained with the WAS vector provide the initial manufacturing and quality control benchmarking that should be helpful to further development and clinical applications.

Wiskott-Aldrich Syndrome (WAS) is a life-threatening X-linked disease characterized by immunodeficiency, thrombocytopenia, autoimmunity, and malignancies. Gene therapy could represent a therapeutic option for patients lacking a suitable bone marrow (BM) donor. In this study, we analyzed the long-term outcome of WAS gene therapy mediated by a clinically compatible lentiviral vector (LV) in a large cohort of was(null) mice. We demonstrated stable and full donor engraftment and Wiskott-Aldrich Syndrome protein (WASP) expression in various hematopoietic lineages, up to 12 months after gene therapy. Importantly, we observed a selective advantage for T and B lymphocytes expressing transgenic WASP. T-cell receptor (TCR)-driven T-cell activation, as well as B-cell's ability to migrate in response to CXCL13, was fully restored. Safety was evaluated throughout the long-term follow-up of primary and secondary recipients of WAS gene therapy. WAS gene therapy did not affect the lifespan of treated animals. Both hematopoietic and non-hematopoietic tumors arose, but we excluded the association with gene therapy in all cases. Demonstration of long-term efficacy and safety of WAS gene therapy mediated by a clinically applicable LV is a key step toward the implementation of a gene therapy clinical trial for WAS. Wiskott-Aldrich Syndrome (WAS) is a life-threatening X-linked disease characterized by immunodeficiency, thrombocytopenia, autoimmunity, and malignancies. Gene therapy could represent a therapeutic option for patients lacking a suitable bone marrow (BM) donor. In this study, we analyzed the long-term outcome of WAS gene therapy mediated by a clinically compatible lentiviral vector (LV) in a large cohort of was(null) mice. We demonstrated stable and full donor engraftment and Wiskott-Aldrich Syndrome protein (WASP) expression in various hematopoietic lineages, up to 12 months after gene therapy. Importantly, we observed a selective advantage for T and B lymphocytes expressing transgenic WASP. T-cell receptor (TCR)-driven T-cell activation, as well as B-cell's ability to migrate in response to CXCL13, was fully restored. Safety was evaluated throughout the long-term follow-up of primary and secondary recipients of WAS gene therapy. WAS gene therapy did not affect the lifespan of treated animals. Both hematopoietic and non-hematopoietic tumors arose, but we excluded the association with gene therapy in all cases. Demonstration of long-term efficacy and safety of WAS gene therapy mediated by a clinically applicable LV is a key step toward the implementation of a gene therapy clinical trial for WAS.