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Hospital de Órbigo, Spain

Rigol M.,University of Barcelona | Solanes N.,University of Barcelona | Roura S.,Hospital Universitari Germans Trias jol | Roque M.,University of Barcelona | And 7 more authors.
European Journal of Clinical Investigation | Year: 2014

Background: Stem cell therapy offers a promising approach to reduce the long-term mortality rate associated with heart failure after acute myocardial infarction (AMI). To date, in vivo translational studies have not yet fully studied the immune response to allogeneic adipose tissue-derived mesenchymal stem cells (ATMSCs). We analysed the immune response and the histological and functional effects of allogeneic ATMSCs in a porcine model of reperfused AMI and determine the effect of administration timing. Design: Pigs that survived AMI (24/26) received intracoronary administration of culture medium after reperfusion (n = 6), ATMSCs after reperfusion (n = 6), culture medium 7 days after AMI (n = 6) or ATMSCs 7 days after AMI (n = 6). At 3-week follow-up, cardiac function, alloantibodies and histological analysis were evaluated. Results: Administration of ATMSCs after reperfusion and 7 days after AMI resulted in similar rates of cell engraftment; some of those cells expressed endothelial, smooth muscle and cardiomyogenic cell lineage markers. Delivery of ATMSCs after reperfusion compared with that performed at 7 days was more effective in increasing: vascular density (249 ± 64 vs. 161 ± 37 vessels/mm2; P < 0·01), T lymphocytes (1 ± 0·4 vs. 0·4 ± 0·3% of area CD3+; P < 0·05) and expression of vascular endothelial growth factor (VEGF; 32 ± 7% vs. 20 ± 4% of area VEGF+; P < 0·01). Allogeneic ATMSC-based therapy did not change ejection fraction but generated alloantibodies. Conclusions: The present study is the first to demonstrate that allogeneic ATMSCs elicit an immune response and, when administered immediately after reperfusion, are more effective in increasing VEGF expression and neovascularization. © 2013 Stichting European Society for Clinical Investigation Journal Foundation. Source

Das A.,University of Lleida | Pushparaj C.,University of Lleida | Bahi N.,University of Lleida | Sorolla A.,University of Lleida | And 6 more authors.
Pigment Cell and Melanoma Research | Year: 2012

The expression of voltage-gated calcium channels (VGCCs) has not been reported previously in melanoma cells in spite of increasing evidence of a role of VGCCs in tumorigenesis and tumour progression. To address this issue we have performed an extensive RT-PCR analysis of VGCC expression in human melanocytes and a range of melanoma cell lines and biopsies. In addition, we have tested the functional expression of these channels using Ca 2+ imaging techniques and examined their relevance for the viability and proliferation of the melanoma cells. Our results show that control melanocytes and melanoma cells express channel isoforms belonging to the Ca v1 and Ca v2 gene families. Importantly, the expression of low voltage-activated Ca v3 (T-type) channels is restricted to melanoma. We have confirmed the function of T-type channels as mediators of constitutive Ca 2+ influx in melanoma cells. Finally, pharmacological and gene silencing approaches demonstrate a role for T-type channels in melanoma viability and proliferation. These results encourage the analysis of T-type VGCCs as targets for therapeutic intervention in melanoma tumorigenesis and/or tumour progression. © 2012 John Wiley & Sons A/S. Source

Das A.,UdL IRBLleida | Pushparaj C.,UdL IRBLleida | Herreros J.,UdL IRBLleida | Nager M.,UdL IRBLleida | And 6 more authors.
Pigment Cell and Melanoma Research | Year: 2013

Summary: We have recently reported that human melanoma cells express a variety of voltage-gated calcium (Ca2+) channel types, including low-voltage-activated T-type channels that play a significant role in melanoma cell cycle progression. Here, we challenged melanoma metastatic cells with T-type channel blockers of clinical use and found a dual effect on cell viability: (i) a reduction in the proliferation rate, through a halt in the progression to the G1-S phase; and (ii) a promotion of cell death that was partially dependent on the activation of caspases. An in-depth analysis of the death process showed that the apoptotic pathway is preceded by endoplasmic reticulum stress and the subsequent inhibition of the basal macroautophagy which is active in these cells. The effects of pharmacological blockers on Ca2+ homeostasis, autophagy, and cell death were mimicked by T-type channel gene silencing. These results provide the basis for a new pharmacological and/or gene silencing approach toward tackling melanoma metastasis. © 2013 John Wiley & Sons A/S. Published by John Wiley & Sons Ltd. Source

Azmanov D.N.,University of Western Australia | Dimitrova S.,Medical University-Sofia | Florez L.,University of Western Australia | Cherninkova S.,Medical University-Sofia | And 20 more authors.
European Journal of Human Genetics | Year: 2011

Primary congenital glaucoma (PCG) is a genetically heterogeneous autosomal recessive disorder, which is an important cause of blindness in childhood. The first known gene, CYP1B1, accounts for a variable proportion of cases in most populations. A second gene, LTBP2, was recently reported in association with a syndrome, in which glaucoma is secondary to lens dislocation. We report on the molecular and clinical profile of 34 families diagnosed as PCG, all originating from the Roma/Gypsy founder population. Comprehensive sequencing analysis revealed a level of heterogeneity unusual for this population, with five CYP1B1 and one ancestral LTBP2 mutation accounting for 70% of patients (25 out of 37) and the remainder still unexplained. Homozygosity for the founder LTBP2 p.R299X mutation resulted in a more severe clinical phenotype and poorer outcome despite a markedly higher number of surgical interventions. The genetically homogeneous group of p.R299X homozygotes showed variable phenotypes (presumably also underlying pathogenetic mechanisms), wherein PCG proper with primary dysgenesis of the trabecular meshwork, and Marfan syndrome-like zonular disease with ectopia lentis and later onset secondary glaucoma are two extremes. The spectrum manifestations may occur in different combinations and have a different evolution even within the same sibship or a single patient. Preliminary observations on compounds with mutations in both CYP1B1-LTBP2 suggest that the observed combinations are of no clinical significance and digenic inheritance is unlikely. We provide a population genetics perspective to explain the allelic heterogeneity, comparing the history and geographic distribution of the two major founder mutations- p.R299X/LTBP2 and p.E387K/CYP1B1. © 2011 Macmillan Publishers Limited All rights reserved. Source

Archila L.D.,Benaroya Research Institute | Jeong D.,Virginia Mason Medical Center | Jeong D.,University of Washington | Pascal M.,Servei dImmunologia | And 8 more authors.
Journal of Allergy and Clinical Immunology | Year: 2015

Background Allergic reactions to walnut can be life-threatening. Although IgE epitopes of walnut have been studied, CD4+ T cell-specific epitopes for walnut remain uncharacterized. In particular, the relationship of both phenotype and frequency of walnut-specific T cells to the disease have not been examined. Objectives We sought to provide a thorough phenotypic analysis for walnut-reactive T cells in allergic and nonallergic subjects, particularly the relationship of phenotypes and frequencies of walnut-specific T cells with the disease. Methods The CD154 upregulation assay was used to examine CD4+ T-cell reactivity toward the walnut allergens Jug r 1, Jug r 2, and Jug r 3. A tetramer-guided epitope mapping approach was used to identify HLA-restricted CD4+ T-cell epitopes in Jug r 2. Direct ex vivo staining with peptide-major histocompatibility complex class II tetramers enabled comparison of the frequency and phenotype of Jug r 2-specific CD4+ T cells between allergic and nonallergic subjects. Jug r 2-specific T-cell clones were also generated, and mRNA transcription factor levels were assessed by using quantitative RT-PCR. Intracellular cytokine staining assays were performed for further phenotypic analyses. Results Jug r 2 was identified as the major allergen that elicited CD4+ T-cell responses. Multiple Jug r 2 T-cell epitopes were identified. The majority of these T cells in allergic subjects have a CCR4+ phenotype. A subset of these T cells express CCR4+CCR6+ irrespective of the asthmatic status of the allergic subjects. Intracellular cytokine staining confirmed these TH2-, TH2/TH17-, and TH17-like heterogenic profiles. Jug r 2-specific T-cell clones from allergic subjects mainly expressed GATA3, nonetheless, a portion of T-cell clones both GATA3 and RAR-related orphan receptor C (RORC) or RORC alone, confirming the presence of TH2, TH2/TH17, and TH17 cells. Conclusions Jug r 2-specific responses dominate walnut T-cell responses in patients with walnut allergy. Jug r 2 central memory CD4+ cells and terminal effector T cells were detected in peripheral blood, with the central memory phenotype as the most prevalent phenotype. In addition to conventional TH2 cells, TH2/TH17 and TH17 cells were also detected in nonasthmatic and asthmatic patients with walnut allergy. Understanding this T-cell heterogeneity might render better understanding of the disease manifestation. © 2015 American Academy of Allergy, Asthma & Immunology. Source

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