19 research outputs found

    Local delivery of fingolimod from three‐dimensional scaffolds impacts islet graft efficacy and microenvironment in a murine diabetic model

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    The local delivery of immunosuppressive agents could significantly promote the success of islet transplantation for the treatment of Type 1 diabetes. Fingolimod, a clinically-approved sphingosine-1-phosphate receptor agonist, has been found to dampen allograft islet rejection in rodent models when delivered systemically. Herein, we engineered a platform for the local delivery of fingolimod by incorporating it within a macroporous polydimethylsiloxane (PDMS) scaffold specifically designed for islet transplantation. In vitro drug release studies quantifying kinetics confirmed sustained release within targeted dose levels for >7 days. Fingolimod-PDMS scaffolds containing syngeneic islets were subsequently transplanted into diabetic mice for examination of the effect of local fingolimod release on engraftment. Surprisingly, either delayed or abrogated efficacy was observed when scaffolds contained a dosage of fingolimod >0.5% w/w; despite drug release rates estimated at ~80-fold less than published systemic delivery reports where no detrimental effects were noted. Histological analysis of explants indicated a dose-dependent modulation of cellular migration and phenotype at the graft site, with high doses impairing host infiltration and engraftment while lower doses promoted leucocyte migration. Mechanistic in vivo and in vitro studies observed unique host and islet responses to local fingolimod delivery, with impairment of murine islet viability and function. Overall, this study confirmed the ability to modulate local delivery of fingolimod in a sustained-release manner using a three-dimensional PDMS scaffold; however, the observed detrimental impacts at the site of islet transplantation do not support further investigation of local delivery at the graft site in murine models

    Documenting a cultural landscape using point-cloud 3d models obtained with geomatic integration techniques. The case of the El Encín atomic garden, Madrid (Spain).

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    A country's cultural landscapes are an important part of its heritage. The growing need to identify, catalogue and preserve these resources has led to a rapid change in the management and inventorying of heritage in general and of cultural landscapes in particular. The main aim of this work is to develop and apply an updated and integrated methodology for capturing and processing geo-information for the digital documentation of cultural heritage. The proposed case study is the atomic garden in the Finca El EncĂ­n (Madrid), a singular space with unique biogeographical features created over 60 years ago. The results of the case study validate the method, consisting of an unmanned aerial platform equipped with sensors to obtain point clouds and aerial images in conjunction with point clouds and images captured with a terrestrial laser scanner

    Dual MET and ERBB inhibition overcomes intratumor plasticity in osimertinib-resistant-advanced non-small-cell lung cancer (NSCLC)

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    BACKGROUND: Third-generation epidermal growth factor receptor tyrosine kinase inhibitors (EGFR-TKIs) such as osimertinib are the last line of targeted treatment of metastatic non-small-cell lung cancer (NSCLC) EGFR-mutant harboring T790M. Different mechanisms of acquired resistance to third-generation EGFR-TKIs have been proposed. It is therefore crucial to identify new and effective strategies to overcome successive acquired mechanisms of resistance. METHODS: For Amplicon-seq analysis, samples from the index patient (primary and metastasis lesions at different timepoints) as well as the patient-derived orthotopic xenograft tumors corresponding to the different treatment arms were used. All samples were formalin-fixed paraffin-embedded, selected and evaluated by a pathologist. For droplet digital PCR, 20 patients diagnosed with NSCLC at baseline or progression to different lines of TKI therapies were selected. Formalin-fixed paraffin-embedded blocks corresponding to either primary tumor or metastasis specimens were used for analysis. For single-cell analysis, orthotopically grown metastases were dissected from the brain of an athymic nu/nu mouse and cryopreserved at -80°C. RESULTS: In a brain metastasis lesion from a NSCLC patient presenting an EGFR T790M mutation, we detected MET gene amplification after prolonged treatment with osimertinib. Importantly, the combination of capmatinib (c-MET inhibitor) and afatinib (ErbB-1/2/4 inhibitor) completely suppressed tumor growth in mice orthotopically injected with cells derived from this brain metastasis. In those mice treated with capmatinib or afatinib as monotherapy, we observed the emergence of KRAS G12C clones. Single-cell gene expression analyses also revealed intratumor heterogeneity, indicating the presence of a KRAS-driven subclone. We also detected low-frequent KRAS G12C alleles in patients treated with various EGFR-TKIs. CONCLUSION: Acquired resistance to subsequent EGFR-TKI treatment lines in EGFR-mutant lung cancer patients may induce genetic plasticity. We assess the biological insights of tumor heterogeneity in an osimertinib-resistant tumor with acquired MET-amplification and propose new treatment strategies in this situation.This work was supported by the Spanish Ministries of Health and Fondo de InvestigaciĂłn Sanitaria-Fondo Europeo de Desarrollo Regional (FEDER) (PI14/01248, PI13-01339, PIE13/00022, PI16/01898); AECC Scientific Foundation (GCB14-2170); and FundaciĂłn Mutua Madrileña (AP150932014). HGP and HH are Miguel Servet researchers funded by the Spanish Institute of Health Carlos III (CPII14/00037, CP14/00229). PN laboratory is funded by the Tumor Biomarker Research Program of the Banco Bilbao Vizcaya Argentaria Foundation (FBBVA
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