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Item type:Publication, IL-10 and IL-6/IL-10 as predictive biomarkers for treatment response in non-infectious uveitis(Frontiers Media SA, 2025-05-13) ;Rodrigo A. Valenzuela ;Fabian Vega-Tapia ;Nathaly Elizalde ;Ivan FloresFelipe M. RojasUveitis, a group of heterogeneous diseases causing ocular inflammation, is a major contributor to vision loss globally. While systemic corticosteroids (CS) are the mainstay treatment, identifying CS-refractory patients remains a significant challenge. This study aimed to explore cytokine expression and Glucocorticoid Receptor (GR) levels as biomarkers for the early detection of CS-refractory cases in non-infectious uveitis. We assayed blood samples from 19 patients with non-infectious uveitis, for the expression of IL-6, IL-17A, TNF-α, IL-10 and GRα. The cohort included 11 refractory and 8 sensitive patients, categorized based on their clinical response to corticosteroids (prednisone 1 mg/kg/day). Blood draws were conducted at three time points (at baseline, day 7- and day 14 after CS initiation), and peripheral blood mononuclear cells (PBMCs) were isolated to measure cytokine and GRα transcript levels via real-time PCR. The expression levels of GRα and cytokines IL-6, IL-17A and TNF-α did not show significant changes between CS-sensitive and CS-refractory patients on the different days of treatment. However, IL-10 expression levels as the day14-to-day7 ratio were significantly higher in patients sensitive to CS therapy. A higher day14-to-day7 ratio was also found for the IL-6/IL-10, IL-17A/IL-10 and GRα/IL-10 ratios. ROC curve analysis demonstrated a robust predictive performance of IL-10 mRNA expression and the IL-6/IL-10 ratio for identifying CS-refractory patients. In conclusion, the expression of IL-10 and the IL-6/IL-10 ratio hold promise as early predictive biomarkers for CS treatment refractoriness in patients with non-infectious uveitis. These findings offer valuable insights into personalized treatment strategies, potentially leading to improved clinical outcomes.Scopus© Citations 6 1 - Some of the metrics are blocked by yourconsent settings
Item type:Publication, Connexin46 in the nucleus of cancer cells: a possible role as transcription modulator(Springer Science and Business Media LLC, 2025-03-27) ;Ainoa Fernández-Olivares ;Viviana P Orellana ;Jesús Llanquinao; Pablo Pérez-MorenoScopus© Citations 1 10 - Some of the metrics are blocked by yourconsent settings
Item type:Publication, TGFβ links EBV to multisystem inflammatory syndrome in children(Springer Science and Business Media LLC, 2025-03-12) ;Carl Christoph Goetzke ;Mona Massoud ;Stefan Frischbutter ;Gabriela Maria GuerraMarta Ferreira-Gomes<jats:title>Abstract</jats:title> <jats:p>In a subset of children and adolescents, SARS-CoV-2 infection induces a severe acute hyperinflammatory shock<jats:sup>1</jats:sup> termed multisystem inflammatory syndrome in children (MIS-C) at four to eight weeks after infection. MIS-C is characterized by a specific T cell expansion<jats:sup>2</jats:sup> and systemic hyperinflammation<jats:sup>3</jats:sup>. The pathogenesis of MIS-C remains largely unknown. Here we show that acute MIS-C is characterized by impaired reactivation of virus-reactive memory T cells, which depends on increased serum levels of the cytokine TGFβ resembling those that occur during severe COVID-19 (refs. <jats:sup>4,5</jats:sup>). This functional impairment in T cell reactivity is accompanied by the presence of TGFβ-response signatures in T cells, B cells and monocytes along with reduced antigen-presentation capabilities of monocytes, and can be reversed by blocking TGFβ. Furthermore, T cell receptor repertoires of patients with MIS-C exhibit expansion of T cells expressing TCRVβ21.3, resembling Epstein–Barr virus (EBV)-reactive T cell clones capable of eliminating EBV-infected B cells. Additionally, serum TGFβ in patients with MIS-C can trigger EBV reactivation, which is reversible with TGFβ blockade. Clinically, the TGFβ-induced defect in T cell reactivity correlates with a higher EBV seroprevalence in patients with MIS-C compared with age-matched controls, along with the occurrence of EBV reactivation. Our findings establish a connection between SARS-CoV-2 infection and COVID-19 sequelae in children, in which impaired T cell cytotoxicity triggered by TGFβ overproduction leads to EBV reactivation and subsequent hyperinflammation.</jats:p>Scopus© Citations 4 2 - Some of the metrics are blocked by yourconsent settings
Item type:Publication, MET Exon 14 Skipping and Novel Actionable Variants: Diagnostic and Therapeutic Implications in Latin American Non-Small-Cell Lung Cancer Patients(MDPI AG, 2024-12-22); ;Romina V. Sepúlveda ;TAPIA DUFEY, JUAN IGNACIO ;Catalina EstayVicente Soto<jats:p>Targeted therapy indications for actionable variants in non-small-cell lung cancer (NSCLC) have primarily been studied in Caucasian populations, with limited data on Latin American patients. This study utilized a 52-genes next-generation sequencing (NGS) panel to analyze 1560 tumor biopsies from NSCLC patients in Chile, Brazil, and Peru. The RNA sequencing reads and DNA coverage were correlated to improve the detection of the actionable MET exon 14 skipping variant (METex14). The pathogenicity of MET variants of uncertain significance (VUSs) was assessed using bioinformatic methods, based on their predicted driver potential. The effects of the predicted drivers VUS T992I and H1094Y on c-MET signaling activation, proliferation, and migration were evaluated in HEK293T, BEAS-2B, and H1993 cell lines. Subsequently, c-Met inhibitors were tested in 2D and 3D cell cultures, and drug affinity was determined using 3D structure simulations. The prevalence of MET variants in the South American cohort was 8%, and RNA-based diagnosis detected 27% more cases of METex14 than DNA-based methods. Notably, 20% of METex14 cases with RNA reads below the detection threshold were confirmed using DNA analysis. The novel actionable T992I and H1094Y variants induced proliferation and migration through c-Met/Akt signaling. Both variants showed sensitivity to crizotinib and savolitinib, but the H1094Y variant exhibited reduced sensitivity to capmatinib. These findings highlight the importance of RNA-based METex14 diagnosis and reveal the drug sensitivity profiles of novel actionable MET variants from an understudied patient population.</jats:p>Scopus© Citations 4 8 - Some of the metrics are blocked by yourconsent settings
Item type:Publication, Prostaglandin E2 Exposure Disrupts E-Cadherin/Caveolin-1-Mediated Tumor Suppression to Favor Caveolin-1-Enhanced Migration, Invasion, and Metastasis in Melanoma Models(2023) ;Lorena Lobos-González ;Lorena Oróstica ;Natalia Díaz-Valdivia ;Victoria Rojas-CelisAmerica Campos<jats:p>Caveolin-1 (CAV1) is a membrane-bound protein that suppresses tumor development yet also promotes metastasis. E-cadherin is important in CAV1-dependent tumor suppression and prevents CAV1-enhanced lung metastasis. Here, we used murine B16F10 and human A375 melanoma cells with low levels of endogenous CAV1 and E-cadherin to unravel how co-expression of E-cadherin modulates CAV1 function in vitro and in vivo in WT C57BL/6 or Rag−/− immunodeficient mice and how a pro-inflammatory environment generated by treating cells with prostaglandin E2 (PGE2) alters CAV1 function in the presence of E-cadherin. CAV1 expression augmented migration, invasion, and metastasis of melanoma cells, and these effects were abolished via transient co-expression of E-cadherin. Importantly, exposure of cells to PGE2 reverted the effects of E-cadherin expression and increased CAV1 phosphorylation on tyrosine-14 and metastasis. Moreover, PGE2 administration blocked the ability of the CAV1/E-cadherin complex to prevent tumor formation. Therefore, our results support the notion that PGE2 can override the tumor suppressor potential of the E-cadherin/CAV1 complex and that CAV1 released from the complex is phosphorylated on tyrosine-14 and promotes migration/invasion/metastasis. These observations provide direct evidence showing how a pro-inflammatory environment caused here via PGE2 administration can convert a potent tumor suppressor complex into a promoter of malignant cell behavior.</jats:p>1Scopus© Citations 5 - Some of the metrics are blocked by yourconsent settings
Item type:Publication, Outcomes of hematopoietic stem cell gene therapy for Wiskott-Aldrich syndrome(2023) ;Roxane Labrosse ;Julia I. Chu ;Myriam A. Armant ;John K. EverettDanilo Pellin<jats:title>Abstract</jats:title> <jats:p>Wiskott-Aldrich syndrome (WAS) is a rare X-linked disorder characterized by combined immunodeficiency, eczema, microthrombocytopenia, autoimmunity, and lymphoid malignancies. Gene therapy (GT) to modify autologous CD34+ cells is an emerging alternative treatment with advantages over standard allogeneic hematopoietic stem cell transplantation for patients who lack well-matched donors, avoiding graft-versus-host-disease. We report the outcomes of a phase 1/2 clinical trial in which 5 patients with severe WAS underwent GT using a self-inactivating lentiviral vector expressing the human WAS complementary DNA under the control of a 1.6-kB fragment of the autologous promoter after busulfan and fludarabine conditioning. All patients were alive and well with sustained multilineage vector gene marking (median follow-up: 7.6 years). Clinical improvement of eczema, infections, and bleeding diathesis was universal. Immune function was consistently improved despite subphysiologic levels of transgenic WAS protein expression. Improvements in platelet count and cytoskeletal function in myeloid cells were most prominent in patients with high vector copy number in the transduced product. Two patients with a history of autoimmunity had flares of autoimmunity after GT, despite similar percentages of WAS protein–expressing cells and gene marking to those without autoimmunity. Patients with flares of autoimmunity demonstrated poor numerical recovery of T cells and regulatory T cells (Tregs), interleukin-10–producing regulatory B cells (Bregs), and transitional B cells. Thus, recovery of the Breg compartment, along with Tregs appears to be protective against development of autoimmunity after GT. These results indicate that clinical and laboratory manifestations of WAS are improved with GT with an acceptable safety profile. This trial is registered at clinicaltrials.gov as #NCT01410825.</jats:p>12Scopus© Citations 30 - Some of the metrics are blocked by yourconsent settings
Item type:Publication, Spent coffee grounds extract: antimicrobial activity against Paenibacillus larvae and its effect on the expression of antimicrobial peptides in Apis mellifera(2023) ;Pablo Giménez-Martínez ;Fabián Zúñiga ;Sandra Medici ;Sandra Fuselli1Scopus© Citations 4 - Some of the metrics are blocked by yourconsent settings
Item type:Publication, Integration of T‐cell clonality screening using <scp>TRBC</scp>‐1 in lymphoma suspect samples by flow cytometry(2023) ;Felipe Castillo ;Constanza Morales ;Biserka Spralja ;Joaquín Díaz‐Schmidt<jats:title>Abstract</jats:title><jats:sec><jats:title>Background</jats:title><jats:p>The diagnosis of T‐cell non‐Hodgkin lymphomas (NHL) is challenging. The development of a monoclonal antibody specific for T‐cell receptor β constant region 1 (TRBC1) provides an alternative to discriminate clonal T cells. The aim of this study was to evaluate the diagnostic potential of an anti‐TRBC1 mAb for the identification of T‐NHL.</jats:p></jats:sec><jats:sec><jats:title>Methods</jats:title><jats:p>We performed a cross‐sectional diagnostic analytic study of samples tested for lymphoma. All samples sent for lymphoma screening were first evaluated using the standard Euroflow LST, to which a second additional custom‐designed T‐cell clonality assessment tube was added CD45/TRBC1/CD2/CD7/CD4/TCRγδ/CD3. Flow cytometry reports were compared with morphological and molecular tests.</jats:p></jats:sec><jats:sec><jats:title>Results</jats:title><jats:p>Fifty‐nine patient samples were evaluated. Within the T‐cell population, cut‐off percentages in the CD4+ cells were from 29.4 to 54.6% and from 23.9 to 52.1% in CD8+ cells. Cut‐off ratios in CD4+ T cells were from 0.33 to 1.1, and in CD8+ cells between 0.22 and 1.0. Using predefined normal cut‐off values, 18 of 59 (30.5%) samples showed a restricted expression of TRBC1. A final diagnosis of a T‐NHL was confirmed clinically and/or by histopathological studies in 15 of the 18 cases (83.3%). There were no cases of T‐NHL by morphology/IHC with normal TRBC1 expression. Non‐neoplastic patient samples behaved between predefined TRBC1 cut‐off values.</jats:p></jats:sec><jats:sec><jats:title>Conclusions</jats:title><jats:p>Expression of TRBC1 provides a robust method for T‐cell clonality assessment, with very high sensitivity and good correlation with complementary methods. TRBC1 can be integrated into routine lymphoma screening strategies via flow cytometry.</jats:p></jats:sec>Scopus© Citations 3 1 - Some of the metrics are blocked by yourconsent settings
Item type:Publication, Helicobacter pylori outer membrane vesicles induce astrocyte reactivity through nuclear factor-κappa B activation and cause neuronal damage in vivo in a murine model(2023) ;Esteban Palacios ;Lorena Lobos-González ;Simón Guerrero ;Marcelo J. KoganBaohai Shao<jats:title>Abstract</jats:title><jats:sec> <jats:title>Background</jats:title> <jats:p><jats:italic>Helicobacter pylori (Hp)</jats:italic> infects the stomach of 50% of the world’s population. Importantly, chronic infection by this bacterium correlates with the appearance of several extra-gastric pathologies, including neurodegenerative diseases. In such conditions, brain astrocytes become reactive and neurotoxic. However, it is still unclear whether this highly prevalent bacterium or the nanosized outer membrane vesicles (OMVs) they produce, can reach the brain, thus affecting neurons/astrocytes. Here, we evaluated the effects of <jats:italic>Hp</jats:italic> OMVs on astrocytes and neurons in vivo and in vitro.</jats:p> </jats:sec><jats:sec> <jats:title>Methods</jats:title> <jats:p>Purified OMVs were characterized by mass spectrometry (MS/MS). Labeled OMVs were administered orally or injected into the mouse tail vein to study OMV-brain distribution. By immunofluorescence of tissue samples, we evaluated: GFAP (astrocytes), βIII tubulin (neurons), and urease (OMVs). The in vitro effect of OMVs in astrocytes was assessed by monitoring NF-κB activation, expression of reactivity markers, cytokines in astrocyte-conditioned medium (ACM), and neuronal cell viability.</jats:p> </jats:sec><jats:sec> <jats:title>Results</jats:title> <jats:p>Urease and GroEL were prominent proteins in OMVs. Urease (OMVs) was present in the mouse brain and its detection coincided with astrocyte reactivity and neuronal damage. In vitro, OMVs induced astrocyte reactivity by increasing the intermediate filament proteins GFAP and vimentin, the plasma membrane α<jats:sub>V</jats:sub>β<jats:sub>3</jats:sub> integrin, and the hemichannel connexin 43. OMVs also produced neurotoxic factors and promoted the release of IFNγ in a manner dependent on the activation of the transcription factor NF-κB. Surface antigens on reactive astrocytes, as well as secreted factors in response to OMVs, were shown to inhibit neurite outgrowth and damage neurons.</jats:p> </jats:sec><jats:sec> <jats:title>Conclusions</jats:title> <jats:p>OMVs administered orally or injected into the mouse bloodstream reach the brain, altering astrocyte function and promoting neuronal damage in vivo. The effects of OMVs on astrocytes were confirmed in vitro and shown to be NF-κB-dependent. These findings suggest that <jats:italic>Hp</jats:italic> could trigger systemic effects by releasing nanosized vesicles that cross epithelial barriers and access the CNS, thus altering brain cells.</jats:p> </jats:sec>Scopus© Citations 36 2 - Some of the metrics are blocked by yourconsent settings
Item type:Publication, Effects of a High-Fat Diet and Docosahexaenoic Acid during Pregnancy on Fatty Acid Composition in the Fetal Livers of Mice(2023) ;Daniela Álvarez ;Macarena Ortiz ;Gabriel Valdebenito ;Nicolás CrisostoBárbara Echiburú<jats:p>A high-fat diet (HFD) during pregnancy promotes fat accumulation and reduces docosahexaenoic acid (DHA) levels in the liver of the offspring at postnatal ages, which can depend on fetal sex. However, the prenatal mechanisms behind these associations are still unclear. Thus, we analyzed if an HFD alters DHA content and the expression of molecules related to fatty acid (FA) metabolism in the fetal liver. Female C57BL/6 mice were fed a control diet or HFD for 4–6 weeks before pregnancy until the gestational day (GD) 17.5. A subgroup of each diet received DHA (100 mg/Kg) orally from GD 6.5 until 16.5. On GD 17.5, maternal livers, placentas, and livers from male and female fetuses were collected for FA profiling with gas-chromatography and gene expression of molecules related to FA metabolism using qPCR. PPAR-α protein expression was evaluated using Western blot. The gene expression of placental FA transporters was also assessed. An HFD increased eicosapentaenoic acid (EPA) and decreased DHA levels and protein expression of PPAR-α in the fetal livers of both sexes. DHA increased the gene expression of Ppara, Cpt1, and Acsl1 in the livers of female fetuses. Therefore, an HFD reduces DHA levels and PPAR-α, a master regulator of gene expression, in the fetal liver. In turn, the livers of female fetuses seem to be more sensitive to DHA action.</jats:p>Scopus© Citations 2