Garcia-Granero, M. (Marta)

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    Methylation status of SOCS1 and SOCS3 in BCR-ABL negative and JAK2V617F negative chronic myeloproliferative neoplasms
    (Elsevier Ltd., 2008-10-01) Cebrián, V. (Virginia); Fernandez-Mercado, M. (Marta); Euba, B. (Begoña); Garcia-Granero, M. (Marta); Novo-Villaverde, F. J. (Francisco Javier); Vizmanos-Pérez, J.L. (José Luis); García-Delgado, M. (Marina); Calasanz-Abinzano, M.J. (Maria Jose)
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    Cellular immunity to hepatitis C virus core protein and the response to interferon in patients with chronic hepatitis C
    (Wiley-Blackwell, 1998) Civeira, M.P. (María Pilar); Borras-Cuesta, F. (Francisco); Lopez, A. (Ascensión); Casares, N. (Noelia); Garcia-Granero, M. (Marta); Prieto, J. (Jesús); Garcia, N. (Nicolás); Lasarte, J.J. (Juan José)
    To investigate the involvement of T-cell response against hepatitis C virus (HCV) antigens in viral clearance after interferon therapy, we measured interleukin-2 (IL-2) production by peripheral mononuclear cells in response to HCV core in patients with chronic hepatitis C. In a cohort of 43 patients, we investigated the frequency of circulating core-specific T-helper (Th) cell precursors by the limiting-dilution assay, and in a second cohort of 60 patients, we analyzed the response to specific core epitopes using 52 synthetic 15-mer overlapping peptides. We observed that the frequency of core-specific Th cell precursors was significantly higher in patients with sustained biochemical and virological response (SR) after interferon (IFN) therapy (median, 1/55,736) than in untreated patients (1/274,023) or that in patients who remained viremic after completion of the treatment-nonresponders (NR) plus transient responders (TR) (1/1,909,972). Patients who failed to respond to IFN (NR) and those who relapsed after IFN discontinuation (TR) had a similarly low number of precursors. The number of core peptides recognized by SR, TR, NR, UT, and healthy controls was 8.2 +/- 1.5, 6.5 +/- 1.2, 2.0 +/- 0.5, 2.7 +/- 0.9, and 0.3 +/- 0.2, respectively. In SR, the intensity of the proliferative response to core peptides as estimated by the summation of stimulation indexes (sigmaSI) was significantly higher than in NR and than in UT, but not different from that of TR. Our results indicate that both expansion of HCV-specific Th cell precursors and Th cell recognition of multiple core epitopes seem to be important in the elimination of HCV after IFN therapy.
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    Midbrain microglia mediate a specific immunosuppressive response under inflammatory conditions
    (Springer Science and Business Media LLC, 2019) Vilas, A. (Amaia); Abellanas-Sánchez, M.A. (Miguel Ángel); San-Martín-Uriz, P. (Patxi); Zamarbide-González, M. (Marta); Aymerich-Soler, M.S. (María Soledad); Basurco, L. (Leyre); Hervas-Stubbs, S. (Sandra); Garcia-Granero, M. (Marta); Mengual, E. (Elisa); Clavero, P. (P.); Luquin, E. (Esther)
    Background: Inflammation is a critical process for the progression of neuronal death in neurodegenerative disorders. Microglia play a central role in neuroinflammation and may affect neuron vulnerability. Next generation sequencing has shown the molecular heterogeneity of microglial cells; however, the variability in their response to pathological inputs remains unknown. Methods: To determine the effect of an inflammatory stimulus on microglial cells, lipopolysaccharide (LPS) was administered peripherally to mice and the inflammatory status of the cortex, hippocampus, midbrain, and striatum was assessed. Microglial activation and interaction with the immune system were analyzed in single cell suspensions obtained from the different brain regions by fluorescence-activated cell sorting, next generation RNA sequencing, real-time PCR, and immunohistochemical techniques. Antigen-presenting properties of microglia were evaluated by the ability of isolated cells to induce a clonal expansion of CD4+ T cells purified from OT-II transgenic mice. Results: Under steady-state conditions, the midbrain presented a high immune-alert state characterized by the presence of two unique microglial subpopulations, one expressing the major histocompatibility complex class II (MHC-II) and acting as antigen-presenting cells and another expressing the toll-like receptor 4 (TLR4), and by the presence of a higher proportion of infiltrating CD4+ T cells. This state was not detected in the cortex, hippocampus, or striatum. Systemic LPS administration induced a general increase in classic pro-inflammatory cytokines, in coinhibitory programmed death ligand 1 (PD-L1), and in cytotoxic T lymphocyte antigen 4 (CTLA-4) receptors, as well as a decrease in infiltrating effector T cells in all brain regions. Interestingly, a specific immune-suppressive response was observed in the midbrain which was characterized by the downregulation of MHC-II microglial expression, the upregulation of the anti-inflammatory cytokines IL10 and TGFβ, and the increase in infiltrating regulatory T cells. Conclusions: These data show that the midbrain presents a high immune-alert state under steady-state conditions that elicits a specific immune-suppressive response when exposed to an inflammatory stimulus. This specific inflammatory tone and response may have an impact in neuronal viability
  • Identification of peptide inhibitors of transforming growth factor beta 1 using a phage-displayed peptide library
    (Elsevier, 2007) Riezu-Boj, J.I. (José Ignacio); Dotor, J. (Javier); Borras-Cuesta, F. (Francisco); Hermida, J. (José); Garcia-Granero, M. (Marta); Prieto, J. (Jesús); Lopez-Vazquez, A.B. (Ana B.); Sarobe, P. (Pablo); Lopez-Sagaseta, J. (Jacinto); Martinez, A. (Alfonso); Feijoo, E. (Esperanza); Lasarte, J.J. (Juan José)
    Pathologies such as liver fibrosis and scleroderma are characterized by harmful levels of transforming growth factor beta 1 (TGFbeta1). These levels could be neutralized if inhibitors of this cytokine were available. With this aim we searched for peptides with binding affinity for TGFbeta1 using a phage-displayed random 15-mer peptide library. Some peptides thus identified blocked activity of TGFbeta1 in vitro, as measured by their capacity to restore growth of Mv-1-Lu cells in presence of added TGFbeta1. Also, they inhibited TGFbeta1-dependent expression of collagen type I mRNA in liver of mice orally insulted with CCl(4). Intraperitoneal administration of 50 microg of peptide P17 (the most active 15-mer peptide, also referred to as P17(1-15)) inhibited expression of collagen type I mRNA by almost 100%. Interestingly, titration experiments showed that P17(1-12) (a peptide encompassing the first 12 amino acids of P17) was approximately four times more active than P17. These results suggest that both peptides, as well as others reported here, may be of therapeutic interest in processes requiring control of undesired high levels of TGFbeta1.
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    A weight-loss model based on baseline microbiota and genetic scores for selection of dietary treatments in overweight and obese population
    (Elsevier, 2022) Martinez, J.A. (José Alfredo); Riezu-Boj, J.I. (José Ignacio); Goñi-Mateos, L. (Leticia); Milagro-Yoldi, F.I. (Fermín Ignacio); Cuevas-Sierra, A. (Amanda); Cuervo, M. (Marta); Garcia-Granero, M. (Marta); Guruceaga, E. (Elizabeth)
    Background & aims: The response to weight loss depends on the interindividual variability of determinants such as gut microbiota and genetics. The aim of this investigation was to develop an integrative model using microbiota and genetic information to prescribe the most suitable diet for a successful weight loss in individuals with excess of body weight. Methods: A total of 190 Spanish overweight and obese participants were randomly assigned to two hypocaloric diets for 4 months: 61 women and 29 men followed a moderately high protein (MHP) diet, and 72 women and 28 men followed a low fat (LF) diet. Baseline fecal DNA was sequenced and used for the construction of four microbiota subscores associated with the percentage of BMI loss for each diet (MHP and LF) and for each sex. Bootstrapping techniques and multiple linear regression models were used for the selection of families, genera and species included in the subscores. Finally, two total microbiota scores were generated for each sex. Two genetic subscores previously reported to weight loss were used to generate a total genetic score. In an attempt to personalize the weight loss prescription, several linear mixed models that included interaction with diet between microbiota scores and genetic scores for both, men and women, were studied. Results: The microbiota subscore for the women who followed the MHP-diet included Coprococcus, Dorea, Flavonifractor, Ruminococcus albus and Clostridium bolteaea. For LF-diet women, Cytophagaceae, Catabacteriaceae, Flammeovirgaceae, Rhodobacteriaceae, Clostridium-x1vb, Bacteriodes nordiiay, Alistipes senegalensis, Blautia wexlerae and Psedoflavonifractor phocaeensis. For MHP-diet men, Cytophagaceae, Acidaminococcaceae, Marinilabiliaceae, Bacteroidaceae, Fusicatenibacter, Odoribacter and Ruminococcus faecis; and for LF-men, Porphyromanadaceae, Intestinimonas, Bacteroides finegoldii and Clostridium bartlettii. The mixed models with microbiota scores facilitated the selection of diet in 72% of women and in 84% of men. The model including genetic information allows to select the type of diet in 84% and 73%, respectively.
  • Simple strategy to induce antibodies of distinct specificity: application to the mapping of gp120 and inhibition of HIV-1 infectivity
    (Wiley-VCH Verlag Berlin, 1995) Riezu-Boj, J.I. (José Ignacio); Berasain, C. (Carmen); Borras-Cuesta, F. (Francisco); Hervas-Stubbs, S. (Sandra); Garcia-Granero, M. (Marta); Prieto, J. (Jesús); Prieto, I. (Isidro); Sarobe, P. (Pablo); Lasarte, J.J. (Juan José)
    In this study 96 15-mer peptides encompassing the entire sequence of HIV-1 gp120 were synthesized and used to immunize BALB/c mice (i) alone or (ii) in conjunction with the T helper cell determinant FISEAIIHVLHSR (FIS) from sperm whale myoglobin, which is well recognized by major histocompatibility complex (MHC) class II molecules of BALB/c. Of these peptides 39 were immunogenic per se and 57 were not. Out of the 57 non-immunogenic peptides 53 could be rendered immunogenic with the second immunization protocol. With the exception of 4 cases, the anti-peptide antibody titers induced in (ii) were equal (14 cases) or higher (78 cases) than those induced in (i). From the 96 anti-peptide antibodies tested, 12 were able to recognize recombinant gp120 with good antibody titers, a result in agreement with previously identified B cell epitopes from gp120 by anti-peptide antibodies induced with longer peptides conjugated to a carrier protein. Moreover, 4 of the 12 anti-peptide antisera that recognized gp 120 were able to neutralize HIV-1 infectivity in vitro, showing that the strategy of co-immunization with FIS may afford functional antibodies.
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    Detection of anti-hepatitis C virus antibodies by ELISA using synthetic peptides
    (Elsevier, 1993) Civeira, M.P. (María Pilar); Riezu-Boj, J.I. (José Ignacio); Berasain, C. (Carmen); Borras-Cuesta, F. (Francisco); Garcia-Granero, M. (Marta); Prieto, J. (Jesús)
    A novel ELISA assay for the detection of anti-hepatitis C virus antibodies in the sera of infected individuals is described. This assay is based on a mixture of three 15-amino acid synthetic peptides encompassing regions of core and NS4 proteins of hepatitis C virus. Comparison with other available ELISA assays based on recombinant polypeptides shows that, short synthetic peptides have the advantage over some larger recombinant peptides by giving higher specificity without loss of sensitivity.
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    Prediction of sustained remission of chronic hepatitis C after a 12-month course of alfa interferon
    (Elsevier, 1994) Civeira, M.P. (María Pilar); Riezu-Boj, J.I. (José Ignacio); Alava, E. (Enrique) de; Camps, J. (J.); Larrea, E. (Esther); Castilla, A. (Alberto); Garcia-Granero, M. (Marta); Prieto, J. (Jesús)
    alpha-Interferon therapy normalizes aminotransferase levels in approximately 50% of the patients with chronic hepatitis C, but post-therapy relapses are common and predictive factors of sustained response remain largely unknown. We retrospectively assessed several parameters as predictors of sustained remission after a 12-month course of lymphoblastoid alpha-interferon: the Knodell histological activity index, serum levels of procollagen type III peptide, serum HCV-RNA, anti-alpha-interferon antibodies, and anti-HCV antibodies (C-100-3), all at month 12. Thirty-seven patients were studied. Fourteen patients were non-responders (38%), 15 patients experienced a sustained response (40.5%) and eight patients responded similarly but relapsed after alpha-interferon withdrawal (21.5%). A decrease in the histological activity index above 5, normalization of procollagen type III peptide levels (< 12 ng/ml) and the absence of viremia after treatment were all significantly associated with a sustained response (p = 0.008, p = 0.007 and p = 0.037, respectively). Anti-interferon antibodies were detected in only one non-responder patient. Anti-C-100-3 antibodies became undetectable at month 12 in 5 of the 15 sustained responders. The best prediction of sustained response was obtained from the three variables independent of multivariate analysis according to the following equation: F = 0.872 + 0.067 x K (decrease of histological index) -0.052 x P (procollagen type III peptide levels at month 12) -0.28 x R (HCV-RNA at month 12; R = 2 when present and R = 1 when absent). A score higher than 0 predicted sustained remission with a 100% sensitivity and specificity in this series of patients.
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    Interaction among sex, aging, and epigenetic processes concerning visceral fat, insulin resistance, and dyslipidaemia
    (Frontiers Media SA, 2019) Santos, J.L. (José Luis); Martinez, J.A. (José Alfredo); Riezu-Boj, J.I. (José Ignacio); Milagro-Yoldi, F.I. (Fermín Ignacio); Arpon, A. (Ana); Garcia-Granero, M. (Marta)
    The distribution of adipose tissue is influenced by gender and by age, shifting from subcutaneous to visceral depots with longevity, increasing the development of several aging-related diseases and manifestations such as obesity, metabolic syndrome, and insulin resistance. Epigenetics might have an important role in aging processes. The aim of this research was to investigate the interactions between aging and epigenetic processes and the role of visceral adipose tissue, insulin resistance, and dyslipidaemia. Two different study samples of 366 and 269 adult participants were analyzed. Anthropometric, biochemical (including the triglycerides-glucose (TyG) index), and blood pressure measurements were assessed following standardized methods. Body composition measurements by Dual-energy X-ray absorptiometry (DXA) were also performed for the second sample. Methylation data were assessed by Infinium Human Methylation BeadChip (Illumina) in peripheral white blood cells. Epigenetic age acceleration was calculated using the methods DNAmAge (AgeAcc) and GrimAge (AgeAccGrim). Age acceleration (AgeAccGrim) showed better correlations than AgeAcc with most of the measured variables (waist circumference, glucose, HOMA-IR, HDL-cholesterol, triglycerides, and TyG index) for the first sample. In the second sample, all the previous correlations were confirmed, except for HOMA-IR. In addition, many of the anthropometrical measurements assessed by DXA and C-reactive protein (CRP) were also statistically associated with AgeAccGrim. Associations separated by sex showed statistically significant correlations between AgeAccGrim and HDL-cholesterol or CRP in women, whereas, in men, the association was with visceral adipose tissue mass DXA, triglycerides and TyG index. Linear regression models (model 1 included visceral adipose tissue mass DXA and TyG index and model 2 included HDL-cholesterol and CRP) showed a significant association for men concerning visceral adipose tissue mass DXA and TyG index, while HDL-cholesterol and CRP were associated in women. Moreover, structural equation modeling showed that the TyG index was mediating the majority of the visceral adipose tissue mass action on age acceleration. Collectively, these findings showed that there are different mechanisms affecting epigenetic age acceleration depending on sex. The identified relationships between epigenetic age acceleration and disease markers will contribute to the understanding of the development of age-related diseases.
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    Prediction of the response of chronic hepatitis C to interferon alfa: a statistical analysis of pretreatment variables
    (BMJ, 1993) Civeira, M.P. (María Pilar); Riezu-Boj, J.I. (José Ignacio); Camps, J. (J.); Cosin, O. (Octavio); Garcia-Granero, M. (Marta); Prieto, J. (Jesús)
    Pretreatment variables that could predict the response of chronic hepatitis C to interferon alfa treatment have not been fully assessed. Eighteen baseline variables were evaluated in a series of 100 consecutive patients treated with a 12 month course of interferon alfa. For the purposes of this study, response was defined as the return to normal of aminotransferase activities before the third month of treatment. Seventy per cent of the patients responded to treatment. Six variables were associated with an increased likelihood of response assessed by univariate analysis. With stepwise multiple regression analysis assessment, however, only three variables remained independently predictive of response: low gamma glutamyltransferase (gamma GT) activities (p < 0.001), absence of obesity (p = 0.005), and absence of cirrhosis (p = 0.01). The response rate in patients with gamma GT activities < 0.66 mu kat/l (n = 55) was 78% and 60% in patients with values > 0.66 mu kat/l (n = 45) (p = 0.048). Response was attained in 75% of non-obese patients (n = 80), compared with only 50% of obese patients (n = 20) (p = 0.03). Finally, 80% of patients without cirrhosis (n = 76) responded, while among those with cirrhosis (n = 24) the response rate was only 37% (p < 0.001). All 23 patients without cirrhosis, <40 years old, and with gamma GT activities <0.66 mu kat/l responded to treatment, while only 28.5% of 14 patients with cirrhosis, >40 years old, and with gamma GT activities >0.66 mu kat/l responded to interferon alfa (p<0.001). Those findings may be useful when evaluating interferon alfa trials and it is suggested that this treatment should be applied early in the course of chronic hepatitis C.