238 research outputs found
L’Estréchure – Église Saint-Martin de Corconac
L’église de Saint-Martin de Corconac se situe dans la vallée Borgne, à mi-distance entre Saint-Jean du Gard et Saumane. Dominant à 322 m d’altitude un méandre du Gardon de Saint-Jean, l’édifice est accessible via la route départementale D39 conduisant, le long de la rive droite, au col du Mercou. Mentionné en 1179 lors de l’hommage rendu par Bérenger de la Balme, seigneur de Bussas, au roi de France, le mansus de Corsenaco dépendait de la seigneurie d’Alès. L’église Sancti-Martini de Corconna..
Nîmes – Ancien couvent des Sœurs Hospitalières, chapelle Saint-Joseph
Pour affiner la connaissance du bâti (cf. BSR 2013) et confirmer les différentes phases de réaménagements de l’ancien couvent des Sœurs Hospitalières, des sondages archéologiques et un suivi de chantier des démontages des cloisonnements ont été souhaités par le service régional de l’archéologie en concertation avec les responsables de la mission Grands projets de Nîmes. La suppression d’un mur en parpaings et d’un faux-plafond ont permis la réouverture et la mise en valeur du volume initial d..
Sabran – Castrum
Dans le cadre d’une demande de protection au titre des monuments historiques, le château de Sabran, situé à 15 km au sud-ouest de la ville de Bagnols-sur-Cèze a fait l’objet de recherches historiques, architecturales et de premières investigations archéologiques afin d’établir un plan topographique. Rattaché à une puissante famille seigneuriale proche de l’entourage du comte de Toulouse dès le xie s., le domaine de Sabran est longtemps resté dans l’oubli des historiens et castellologues. Ment..
Exploration of the Lysis Mechanisms of Leukaemic Blasts by Chimaeric T-Cells
Adoptive transfer of specific cytotoxic T lymphocytes (CTL) and Cytokine Induced Killer Cells (CIK) following genetic engineering of T-cell receptor zeta hold promising perspective in immunotherapy. In the present work we focused on the mechanisms of anti-tumor action of effectors transduced with an anti-CD19 chimaeric receptor in the context of B-lineage acute lymphoblastic leukemia (B-ALL).
Primary B-ALL blasts were efficiently killed by both z-CD19 CTL and z-CD19 CIK effectors. The use of death receptor mediated apoptosis of target cells was excluded since agonists molecules of Fas and TRAIL-receptors failed to induce cell death. Perforin/granzyme pathway was found to be the mechanism of chimaeric effectors mediated killing. Indeed, cytolytic effector molecules perforin as well as granzymes were highly expressed by CTL and CIK. CD19 specific stimulation of transduced effectors was associated with degranulation as attested by CD107 membrane expression and high IFN-γ and TNF-α release. Moreover inhibitors of the perforin-based cytotoxic pathway, Ca2+-chelating agent EGTA and Concanamycin A, almost completely abrogated B-ALL blast killing.
In conclusion we show that the cytolysis response of z-CD19 chimaeric effectors is predominantly mediated via perforin/granzyme pathway and is independent of death receptors signaling in primary B-ALL
Breast cancer instructs dendritic cells to prime interleukin 13–secreting CD4+ T cells that facilitate tumor development
We previously reported (Bell, D., P. Chomarat, D. Broyles, G. Netto, G.M. Harb, S. Lebecque, J. Valladeau, J. Davoust, K.A. Palucka, and J. Banchereau. 1999. J. Exp. Med. 190: 1417–1426) that breast cancer tumors are infiltrated with mature dendritic cells (DCs), which cluster with CD4+ T cells. We now show that CD4+ T cells infiltrating breast cancer tumors secrete type 1 (interferon γ) as well as high levels of type 2 (interleukin [IL] 4 and IL-13) cytokines. Immunofluorescence staining of tissue sections revealed intense IL-13 staining on breast cancer cells. The expression of phosphorylated signal transducer and activator of transcription 6 in breast cancer cells suggests that IL-13 actually delivers signals to cancer cells. To determine the link between breast cancer, DCs, and CD4+ T cells, we implanted human breast cancer cell lines in nonobese diabetic/LtSz-scid/scid β2 microglobulin–deficient mice engrafted with human CD34+ hematopoietic progenitor cells and autologous T cells. There, CD4+ T cells promote early tumor development. This is dependent on DCs and can be partially prevented by administration of IL-13 antagonists. Thus, breast cancer targets DCs to facilitate its development
Circulating and Hepatic BDCA1+, BDCA2+, and BDCA3+ Dendritic Cells Are Differentially Subverted in Patients With Chronic HBV Infection
Background and aims: Chronic hepatitis B virus (HBV) infection is a major health burden potentially evolving toward cirrhosis and hepatocellular carcinoma. HBV physiopathology is strongly related to the host immunity, yet the mechanisms of viral evasion from immune-surveillance are still misunderstood. The immune response elicited at early stages of viral infection is believed to be important for subsequent disease outcome. Dendritic cells (DCs) are crucial immune sentinels which orchestrate antiviral immunity, which offer opportunity to pathogens to subvert them to escape immunity. Despite the pivotal role of DCs in orientating antiviral responses and determining the outcome of infection, their precise involvement in HBV pathogenesis is not fully explored.Methods: One hundred thirty chronically HBV infected patients and 85 healthy donors were enrolled in the study for blood collection, together with 29 chronically HBV infected patients and 33 non-viral infected patients that were included for liver biopsy collection. In a pioneer way, we investigated the phenotypic and functional features of both circulating and intrahepatic BDCA1+ cDC2, BDCA2+ pDCs, and BDCA3+ cDC1 simultaneously in patients with chronic HBV infection by designing a unique multi-parametric flow cytometry approach.Results: We showed modulations of the frequencies and basal activation status of blood and liver DCs associated with impaired expressions of specific immune checkpoints and TLR molecules on circulating DC subsets. Furthermore, we highlighted an impaired maturation of circulating and hepatic pDCs and cDCs following stimulation with specific TLR agonists in chronic HBV patients, associated with drastic dysfunctions in the capacity of circulating DC subsets to produce IL-12p70, TNFα, IFNα, IFNλ1, and IFNλ2 while intrahepatic DCs remained fully functional. Most of these modulations correlated with HBsAg and HBV DNA levels.Conclusion: We highlight potent alterations in the distribution, phenotype and function of all DC subsets in blood together with modulations of intrahepatic DCs, revealing that HBV may hijack the immune system by subverting DCs. Our findings provide innovative insights into the immuno-pathogenesis of HBV and the mechanisms of virus escape from immune control. Such understanding is promising for developing new therapeutic strategies restoring an efficient immune control of the virus
Theoretical approach based on Monte-Carlo simulations to predict the cell survival following BNCT
International audienceWe present here a very preliminary work on BNCT Dosimetry. The approach is as follows:A full Monte Carlo calculation is used to separate all dose components and determine the corresponding physical dose fractions with a realistic clinical model.These dose fractions are then used as mixed fields to predict cell-survivals and RBE values for a specific cell-line, thanks to the radiobiological model NanOxTM
Colon Cancer Stem Cells Dictate Tumor Growth and Resist Cell Death by Production of Interleukin-4
A novel paradigm in tumor biology suggests that cancer growth is driven by stem-like cells within a tumor. Here, we describe the identification and characterization of such cells from colon carcinomas using the stem cell marker CD133 that accounts around 2% of the cells in human colon cancer. The CD133+ cells grow in vitro as undifferentiated tumor spheroids, and they are both necessary and sufficient to initiate tumor growth in immunodeficient mice. Xenografts resemble the original human tumor maintaining the rare subpopulation of tumorigenic CD133+ cells. Further analysis revealed that the CD133+ cells produce and utilize IL-4 to protect themselves from apoptosis. Consistently, treatment with IL-4Rα antagonist or anti-IL-4 neutralizing antibody strongly enhances the antitumor efficacy of standard chemotherapeutic drugs through selective sensitization of CD133+ cells. Our data suggest that colon tumor growth is dictated by stem-like cells that are treatment resistant due to the autocrine production of IL-4
Thymic stromal lymphopoietin fosters human breast tumor growth by promoting type 2 inflammation
TSLP released from human breast cancer cells promotes OX40L expression on DCs, and these OX40L-expressing DCs drive development of inflammatory Th2 cells which promote breast tumor development
Prevention of type 1 diabetes in mice by tolerogenic vaccination with a strong agonist insulin mimetope
Subimmunogenic vaccination with an agonist mimetope of insulin converts naive T cells into regulatory T cells and prevents type 1 diabetes in NOD mice
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