Publications by authors named "Ramon Merino"

MYC is an oncogenic transcription factor dysregulated in about half of total human tumors. While transcriptomic studies reveal more than 1000 genes regulated by MYC, a much smaller fraction of genes is directly transactivated by MYC. Virtually all Burkitt lymphoma (BL) carry chromosomal translocations involving MYC oncogene.

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The downstream signaling of the interleukin-7 (IL-7) receptor (IL-7R) plays important physiological and pathological roles, including the differentiation of lymphoid cells and proliferation of acute lymphoblastic leukemia cells. Gain-of-function mutations in the IL-7Rα chain, the specific component of the receptor for IL-7, result in constitutive, IL-7-independent signaling and trigger acute lymphoblastic leukemia. Here, we show that the loss of the phosphoinositide 5-phosphatase INPP5K is associated with increased levels of the INPP5K substrate phosphatidylinositol 4,5-bisphosphate (PtdIns[4,5]P2) and causes an altered dynamic structure of the IL-7 receptor.

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In CD38-deficient ( mice intraperitoneal injection of pristane induces a lupus-like disease, which is milder than that induced in WT mice, showing significant differences in the inflammatory and autoimmune processes triggered by pristane. Extracellular vesicles (EV) are present in all body fluids. Shed by cells, their molecular make-up reflects that of their cell of origin and/or tissue pathological situation.

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Systemic sclerosis (SSc) is an autoimmune disease that affects skin and multiple internal organs. TGF-β, a central trigger of cutaneous fibrosis, activates fibroblasts with the involvement of the stress-inducible chaperone heat shock protein 90 isoform α (Hsp90α). Available evidence supports overexpression and secretion of Hsp90α as a feature in profibrotic pathological conditions.

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The absence of the mouse cell surface receptor CD38 in mice suggests that this receptor acts as a positive regulator of inflammatory and autoimmune responses. Here, we report that, in the context of the chronic graft--host disease (cGVHD) lupus inducible model, the transfer of B6.C-H2bm12/KhEg(bm12) spleen cells into co-isogenic B6 mice causes milder lupus-like autoimmunity with lower levels of anti-ssDNA autoantibodies than the transfer of bm12 spleen cells into WT B6 mice.

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Objective: The transforming growth factor β (TGFβ) inhibitor BAMBI (bone morphogenetic protein and activin membrane-bound inhibitor) has been shown to control differentiation of CD4+ T lymphocytes into either tolerogenic Treg cells or pathogenic Th17 cells, through the regulation of TGFβ and interleukin-2 (IL-2) signaling strength. The present study was undertaken to explore the potential beneficial effects of this strategy of pharmacologic inhibition using novel anti-BAMBI monoclonal antibodies (mAb) in different experimental murine models of chronic skin and joint inflammatory/autoimmune disease.

Methods: Development of Saccharomyces cerevisiae mannan-induced psoriatic arthritis (MIP) (n = 18-30 mice per group), imiquimod-induced skin psoriasis (n = 20-30 mice per group), or type II collagen-induced arthritis (CIA) (n = 13-16 mice per group) was analyzed in a total of 2-5 different experiments with either wild-type (WT) or BAMBI-deficient B10.

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Background: CD6 is a lymphocyte surface co-receptor physically associated with the T-cell receptor (TCR)/CD3 complex at the center of the immunological synapse. There, CD6 assists in cell-to-cell contact stabilization and modulation of activation/differentiation events through interaction with CD166/ALCAM (activated leukocyte cell adhesion molecule), its main reported ligand. While accumulating evidence is attracting new interest on targeting CD6 for therapeutic purposes in autoimmune disorders, little is known on its potential in cancer.

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The TGFβ superfamily is composed of more than 33 growth and differentiation factors, including TGFβ1, β2, β3, BMPs, GDFs, nodal-related proteins, and activins. These members usually exert pleiotropic actions on several tissues and control multiple cellular processes, such as cell growth, cell survival, cell migration, cell fate specification, and differentiation, both during embryonic development and postnatal life. Although the effects of these factors on immune responses were elucidated long ago, most studies have been focused on the actions of TGFβs on T cells, as major regulators of adaptive immunity.

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Down syndrome (DS) is characterized by structural and functional anomalies that are present prenatally and that lead to intellectual disabilities. Later in life, the cognitive abilities of DS individuals progressively deteriorate due to the development of Alzheimer's disease (AD)-associated neuropathology (i.e.

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In this study, we investigated the role of CD38 in a pristane-induced murine model of lupus. CD38-deficient (Cd38) but not ART2-deficient (Art2) mice developed less severe lupus compared to wild type (WT) mice, and their protective phenotype consisted of (i) decreased IFN-I-stimulated gene expression, (ii) decreased numbers of peritoneal CCR2Ly6C inflammatory monocytes, TNF-α-producing Ly6G neutrophils and Ly6C monocytes/macrophages, (iii) decreased production of anti-single-stranded DNA and anti-nRNP autoantibodies, and (iv) ameliorated glomerulonephritis. Cd38 pristane-elicited peritoneal exudate cells had defective CCL2 and TNF-α secretion following TLR7 stimulation.

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Objective: Map3k8 (Cot/Tpl2) activates the MKK1/2-ERK1/2, MAPK pathway downstream from interleukin-1R, tumor necrosis factor-αR, NOD-2R (nucleotide-binding oligomerization domain-like 2R), adiponectinR, and Toll-like receptors. Map3k8 plays a key role in innate and adaptive immunity and influences inflammatory processes by modulating the functions of different cell types. However, its role in atherogenesis remains unknown.

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Stress-activated transcription factors influence T-cell function in different physiopathologic contexts. NFAT5, a relative of nuclear factor κB and the calcineurin-activated NFATc transcription factors, protects mammalian cells from hyperosmotic stress caused by the elevation of extracellular sodium levels. In T cells exposed to hypernatremia, NFAT5 not only induces osmoprotective gene products but also cytokines and immune receptors, which raises the question of whether this factor could regulate other T-cell functions in osmostress-independent contexts.

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The inhibition of apoptotic cell death in T cells through the dysregulated expression of BCL2 family members has been associated with the protection against the development of different autoimmune diseases. However, multiple mechanisms were proposed to be responsible for such protective effect. The purpose of this study was to explore the effect of the T-cell overexpression of BCL2A1, an anti-apoptotic BCL2 family member without an effect on cell cycle progression, in the development of collagen-induced arthritis.

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The CD6 glycoprotein is a lymphocyte surface receptor putatively involved in T cell development and activation. CD6 facilitates adhesion between T cells and antigen-presenting cells through its interaction with CD166/ALCAM (activated leukocyte cell adhesion molecule), and physically associates with the T cell receptor (TCR) at the center of the immunological synapse. However, its precise role during thymocyte development and peripheral T cell immune responses remains to be defined.

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Objective: Transforming growth factor β (TGFβ) plays a prominent role in the establishment of immunologic tolerance, and mice lacking TGFβ1 die of multiorgan inflammation early in life. TGFβ controls the differentiation of CD4+ lymphocytes into Treg cells or proinflammatory Th17 cells. Although this dual capacity is modulated by the presence of additional cytokines around the activated cells, TGFβ also dissociates Th17/Treg cell differentiation in a dose-dependent manner by mechanisms still unknown.

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Collagen-type-II-induced arthritis (CIA) is an autoimmune disease, which involves a complex host systemic response including inflammatory and autoimmune reactions. CIA is milder in CD38(-/-) than in wild-type (WT) mice. ProteoMiner-equalized serum samples were subjected to 2D-DiGE and MS-MALDI-TOF/TOF analyses to identify proteins that changed in their relative abundances in CD38(-/-) versus WT mice either with arthritis (CIA(+) ), with no arthritis (CIA(-) ), or with inflammation (complete Freund's adjuvant (CFA)-treated mice).

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CD5 is a lymphoid-specific transmembrane glycoprotein constitutively expressed on thymocytes and mature T and B1a lymphocytes. Current data support the view that CD5 is a negative regulator of antigen-specific receptor-mediated signaling in these cells, and that this would likely be achieved through interaction with CD5 ligand/s (CD5L) of still undefined nature expressed on immune or accessory cells. To determine the functional consequence of loss of CD5/CD5L interaction in vivo, a new transgenic mouse line was generated (shCD5EμTg), expressing a circulating soluble form of human CD5 (shCD5) as a decoy to impair membrane-bound CD5 function.

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Objective: Despite the importance of Treg cells in the maintenance of immunologic tolerance, the mechanisms that control their generation and activity are unknown. Since the cell cycle inhibitor p27(Kip1) (p27) was involved in T cell anergy, we undertook this study to explore its role in both Treg cell processes.

Methods: The development of type II collagen-induced arthritis (CIA) and lupus-like abnormalities was compared between transgenic mice overexpressing human Bcl-2 in T cells (BCL2-TgT mice) and nontransgenic mice that were deficient or not deficient in p27.

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CD38, a type II transmembrane glycoprotein expressed in many cells of the immune system, is involved in cell signaling, migration and differentiation. Studies in CD38 deficient mice (CD38 KO mice) indicate that this molecule controls inflammatory immune responses, although its involvement in these responses depends on the disease model analyzed. Here, we explored the role of CD38 in the control of autoimmune responses using chicken collagen type II (col II) immunized C57BL/6-CD38 KO mice as a model of collagen-induced arthritis (CIA).

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Objective: Review of the Guidelines which have major impact on the urological field, in order to compare and to know their recommendations in the diagnosis and management of biochemical relapse after a healing treatment of prostate cancer (radical prostatectomy or radiotherapy).

Methods: We review the Guidelines of the European Urological Association (EAU), the American Urological Association (AUA), of the National Comprehensive Cancer Network (NCCN) and those of the National Institute for Health and Clinical Excellence (NICE), as well as the scientific evidence on which they are based.

Results: In this paper we state the complexity of the subject being dealt with and coincidences and differences among them.

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Objective: To explore the bidirectional relationship between the development of rheumatoid arthritis (RA) and atherosclerosis using bovine type II collagen (CII)-immunized B10.RIII apoE(-/-) mice, a murine model of spontaneous atherosclerosis and collagen-induced arthritis (CIA).

Methods: Male B10.

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Genetic abnormalities predisposing to autoimmunity generally act in a cooperative manner affecting one or several mechanisms regulating immunological tolerance. In addition, many of these genetic abnormalities are also involved in the development of lymphoproliferative diseases. In the present study, we have determined the possible cooperation between deficiencies in members of the Cip/Kip family of cell cycle regulators (p21(WAF1/Cip1) or p27(kip1)) and the overexpression of human Bcl-2 in B lymphocytes in the induction of autoimmune and lymphoproliferative diseases in non-autoimmune C57BL/6 (B6) mice.

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Objectives: The contribution of humoral immune response in allograft and xenograft rejection has been clearly demonstrated in recent years. For this reason, inhibition of alloantibody production has become essential in managing transplanted patients. Here, we assessed the effects of the leflunomide derivative FK778 (FK778) in the control of antibody production resulting from semiallogeneic cognate T-B-cell interactions.

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Transforming growth factors-beta (TGF-betas) signal through type I and type II serine-threonine kinase receptor complexes. During ligand binding, type II receptors recruit and phosphorylate type I receptors, triggering downstream signaling. BAMBI [bone morphogenetic protein (BMP) and activin membrane-bound inhibitor] is a transmembrane pseudoreceptor structurally similar to type I receptors but lacks the intracellular kinase domain.

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The Escherichia coli heat-labile enterotoxin (LT) possesses a powerful mucosal and systemic adjuvant effect. However, little is known about the cellular and molecular basis of the immunostimulatory activity of LT at the mucosal level, and even less information is available on the mechanisms underlying its systemic adjuvant activity. In this study, we show that distinct mechanisms are responsible for the parenteral and mucosal adjuvanticity of LT.

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