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Alvarez-Arellano L.,Hospital Of Pediatria Del Instituto Mexicano Del Seguro Social | Alvarez-Arellano L.,National Autonomous University of Mexico | Cortes-Reynosa P.,National Polytechnic Institute of Mexico | Sanchez-Zauco N.,Hospital Of Pediatria Del Instituto Mexicano Del Seguro Social | And 5 more authors.
PLoS ONE | Year: 2014

Helicobacter pylori infection represents one of the most common bacterial infections worldwide. The inflammatory response to this bacterium involves a large influx of neutrophils to the lamina propria of the gastric mucosa. However, little is known about the receptors and molecular mechanisms involved in activation of these neutrophils. In this study, we aimed to determine the role of toll-like receptor 9 (TLR9) in the response of human neutrophils to H. pylori and purified H. pylori DNA (Hp-DNA). Neutrophils were isolated from the blood of adult volunteers and challenged with either H. pylori or Hp-DNA. We found that both, H. pylori and Hp-DNA induced increased expression and release of IL-8. Furthermore, we showed that TLR9 is involved in the induction of IL-8 production by H. pylori and Hp-DNA. IL-8 production induced by H. pylori but not by Hp-DNA was partially mediated by NF-κB. In conclusion, this study showed for first time that both, H. pylori and Hp-DNA activate TLR9 and induce a different inflammatory response that leads to activation of neutrophils. © 2014 Alvarez-Arellano et al. Source

Sanchez-Zauco N.,Laboratorio Of Investigacion En Inmunologia Y Proteomica | Rio-Navarro B.D.,Hospital Infantil de Mexico Federico Gomez | Gallardo-Casas C.,National Polytechnic Institute of Mexico | Del Rio-Chivardi J.,Hospital Infantil de Mexico Federico Gomez | And 3 more authors.
Allergy and Asthma Proceedings | Year: 2014

Asthma is a common pulmonary disease with chronic inflammation of the airways, and obesity is a chronic state of low-grade inflammation. Toll-like receptors (TLRs) are involved in the innate immune response. This study was designed to analyze whether obesity has an effect on the immune response of patients with asthma. We included obese asthmatic, obese, asthmatic, and healthy children. Biochemical and anthropometric analyses were performed. Interleukin (IL)-2, interferon (IFN) gamma, IL-4, IL-10, IL-1beta, and tumor necrosis factor alpha were measured. Peripheral blood mononuclear cells were analyzed by immunostaining with anti-TLR2 and anti-TLR9 antibodies. The data were expressed as means ± SEM or medians and percentiles. Kruskal-Wallis test and Dunn's multiple comparison test were applied. Asthmatic patients, both obese and nonobese, exhibited a mild asthma phenotype; none had infectious process, exacerbation, or acute symptoms during the 30 days before the inclusion in the study. The IL-2 and IFN-gamma levels in the obese asthmatic group were lower than in the other three groups. IL-4 levels in the obese asthmatic group were almost equal to those of the asthmatic group and more than in the other two groups, without significant difference. There were higher levels of TLR2 and TLR9 in obese asthmatic patients than in the other three groups. There is a decrease in Th1 cytokines in obese asthmatic patients, and we only found a trend to an increased Th2 profile. Patients studied do not appear to fit into any of the endotypes described until now. This is the first study showing the high expression of TLR2 and TLR9 in obese asthmatic patients. It is necessary to study other cytokines in obese asthmatic patients to see if it is possible to fit them into any of the already described endotypes or if it is a distinct endotype. Copyright © 2014, OceanSide Publications, Inc.,. Source

Martinez-Armenta M.,National Autonomous University of Mexico | Diaz de Leon-Guerrero S.,National Autonomous University of Mexico | Diaz de Leon-Guerrero S.,Laboratorio Of Investigacion En Inmunologia Y Proteomica | Catalan A.,National Autonomous University of Mexico | And 5 more authors.
Molecular and Cellular Endocrinology | Year: 2015

The hypothalamus regulates the homeostasis of the organism by controlling hormone secretion from the pituitary. The molecular mechanisms that regulate the differentiation of the hypothalamic thyrotropin-releasing hormone (TRH) phenotype are poorly understood. We have previously shown that Klf10 or TGFβ inducible early gene-1 (TIEG1) is enriched in fetal hypothalamic TRH neurons. Here, we show that expression of TGFβ isoforms (1-3) and both TGFβ receptors (TβRI and II) occurs in the hypothalamus concomitantly with the establishment of TRH neurons during late embryonic development. TGFβ2 induces Trh expression via a TIEG1 dependent mechanism. TIEG1 regulates Trh expression through an evolutionary conserved GC rich sequence on the Trh promoter. Finally, in mice deficient in TIEG1, Trh expression is lower than in wild type animals at embryonic day 17. These results indicate that TGFβ signaling, through the upregulation of TIEG1, plays an important role in the establishment of Trh expression in the embryonic hypothalamus. © 2014 Published by Elsevier Ireland Ltd. Source

Gerard A.,University of California at San Francisco | Patino-Lopez G.,U.S. National Cancer Institute | Patino-Lopez G.,Laboratorio Of Investigacion En Inmunologia Y Proteomica | Beemiller P.,University of California at San Francisco | And 7 more authors.
Cell | Year: 2014

To mount an immune response, T lymphocytes must successfully search for foreign material bound to the surface of antigen-presenting cells. How T cells optimize their chances of encountering and responding to these antigens is unknown. T cell motility in tissues resembles a random or Levy walk and is regulated in part by external factors including chemokines and lymph-node topology, but motility parameters such as speed and propensity to turn may also be cell intrinsic. Here we found that the unconventional myosin 1g (Myo1g) motor generates membrane tension, enforces cell-intrinsic meandering search, and enhances T-DC interactions during lymph-node surveillance. Increased turning and meandering motility, as opposed to ballistic motility, is enhanced by Myo1g. Myo1g acts as a "turning motor" and generates a form of cellular "flânerie." Modeling and antigen challenges show that these intrinsically programmed elements of motility search are critical for the detection of rare cognate antigen-presenting cells. PaperClip © 2014 Elsevier Inc. Source

Hernandez E.G.,National Autonomous University of Mexico | Granados J.,Instituto Nacional Of Ciencias Medicas Y Nutricion Salvador Zubiran Incmnsz | Partida-Rodriguez O.,National Autonomous University of Mexico | Valenzuela O.,University of Sonora | And 13 more authors.
PLoS ONE | Year: 2015

Amebiasis is an endemic disease and a public health problem throughout Mexico, although the incidence rates of amebic liver abscess (ALA) vary among the geographic regions of the country. Notably, incidence rates are high in the northwestern states (especially Sonora with a rate of 12.57/100,000 inhabitants) compared with the central region (Mexico City with a rate of 0.69/100,000 inhabitants). These data may be related to host genetic factors that are partially responsible for resistance or susceptibility. Therefore, we studied the association of the HLA-DRB1 and HLA-DQB1 alleles with resistance or susceptibility to ALA in two Mexican populations, one each from Mexico City and Sonora. Ninety ALA patients were clinically diagnosed by serology and sonography. Genomic DNA was extracted from peripheral blood mononuclear cells. To establish the genetic identity of both populations, 15 short tandem repeats (STRs) were analyzed with multiplexed PCR, and the allelic frequencies of HLA were studied by PCR-SSO using LUMINEX technology. The allele frequencies obtained were compared to an ethnically matched healthy control group (146 individuals). We observed that both affected populations differed genetically from the control group. We also found interesting trends in the population from Mexico City. HLA-DQB1∗02 allele frequencies were higher in ALA patients compared to the control group (0.127 vs 0.047; p= 0.01; pc= NS; OR= 2.9, 95% CI= 1.09-8.3). The less frequent alleles in ALA patients were HLADRB1∗08 (0.118 vs 0.238 in controls; p= 0.01; pc= NS; OR= 0.42, 95% CI= 0.19-0.87) and HLA-DQB1∗04 (0.109 vs 0.214; p= 0.02; pc= NS; OR= 0.40, 95% CI= 0.20-0.94). The haplotype HLA-DRB1∗08/-DQB1∗04 also demonstrated a protective trend against the development of this disease (0.081 vs. 0.178; p=0.02; pc=NS; OR= 0.40, 95% CI= 0.16-0.93). These trends suggest that the prevalent alleles in the population of Mexico City may be associated with protection against the development of ALA. © 2015 Hernández et al. Source

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