Browsing by Author "Riedel, Claudia A."
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- ItemAldosterone Promotes Autoimmune Damage by Enhancing Th17-Mediated Immunity(AMER ASSOC IMMUNOLOGISTS, 2010) Herrada, Andres A.; Contreras, Francisco J.; Marini, Natacha P.; Amador, Cristian A.; Gonzalez, Pablo A.; Cortes, Claudia M.; Riedel, Claudia A.; Carvajal, Cristian A.; Figueroa, Fernando; Michea, Luis F.; Fardella, Carlos E.; Kalergis, Alexis M.Excessive production of aldosterone leads to the development of hypertension and cardiovascular disease by generating an inflammatory state that can be promoted by T cell immunity. Because nature and intensity of T cell responses is controlled by dendritic cells (DCs), it is important to evaluate whether the function of these cells can be modulated by aldosterone. In this study we show that aldosterone augmented the activation of CD8(+) T cells in a DC-dependent fashion. Consistently, the mineralocorticoid receptor was expressed by DCs, which showed activation of MAPK pathway and secreted IL-6 and TGF-beta in response to aldosterone. In addition, DCs stimulated with aldosterone impose a Th17 phenotype to CD4(+) T cells, which have recently been associated with the promotion of inflammatory and autoimmune diseases. Accordingly, we observed that aldosterone enhances the progression of experimental autoimmune encephalomyelitis, an autoimmune disease promoted by Th17 cells. In addition, blockade of the mineralocorticoid receptor prevented all aldosterone effects on DCs and attenuated experimental autoimmune encephalomyelitis development in aldosterone-treated mice. Our data suggest that modulation of DC function by aldosterone enhances CD8(+) T cell activation and promotes Th17-polarized immune responses, which might contribute to the inflammatory damage leading to hypertension and cardiovascular disease. The Journal of Immunology, 2010, 184: 191-202.
- ItemAltered Chemokine Receptor Expression in Papillary Thyroid Cancer(MARY ANN LIEBERT, INC, 2009) Gonzalez, Hernan E.; Leiva, Andrea; Tobar, Hugo; Boehmwald, Karen; Tapia, Grace; Torres, Javiera; Mosso, Lorena M.; Bueno, Susan M.; Gonzalez, Pablo; Kalergis, Alexis M.; Riedel, Claudia A.Background: Papillary thyroid cancer (PTC), the most prevalent type of differentiated thyroid carcinoma, displays a strikingly high frequency of lymph node metastasis (LNM). Recent data suggest that chemokines can play an important role in promoting tumor progression and metastatic migration of tumor cells. Here we have evaluated whether PTC tissues express a different pattern of chemokine receptors and if the expression of these receptors correlates with LNM.
- ItemAssessing the Importance of Domestic Vaccine Manufacturing Centers: An Overview of Immunization Programs, Vaccine Manufacture, and Distribution(2018) Rey-Jurado, Emma; Tapia, Felipe; Munoz-Durango, Natalia; Lay, Margarita K.; Carreno, Leandro J.; Riedel, Claudia A.; Bueno Ramírez, Susan; Genzel, Yvonne; Kalergis Parra, Alexis Mikes
- ItemCharacterization of the anti-inflammatory capacity of IL-10-Producing neutrophils in response to streptococcus pneumoniae infection(FRONTIERS MEDIA SA, 2021) González Carreño, Liliana Andrea; Melo González, Felipe Andrés; Sebastián Quijada, Valentina Pilar; Vallejos Galvez, Omar Patricio; Noguera Mijares, Loreani Paola; Suazo Galvez, Isidora del Carmen; Schultz Lombardic, Bárbara M.; Manosalva, Andres H.; Peñaloza, Hernán F.; Soto Ramírez, Jorge Andres; Parker, Dane; Riedel, Claudia A.; González Muñoz, Pablo Alberto; Kalergis Parra, Alexis Mikes; Bueno Ramírez, SusanNeutrophils are immune cells classically defined as pro-inflammatory effector cells. However, current accumulated evidence indicates that neutrophils have more versatile immune-modulating properties. During acute lung infection with Streptococcus pneumoniae in mice, interleukin-10 (IL-10) production is required to temper an excessive lung injury and to improve survival, yet the cellular source of IL-10 and the immunomodulatory role of neutrophils during S. pneumoniae infection remain unknown. Here we show that neutrophils are the main myeloid cells that produce IL-10 in the lungs during the first 48 h of infection. Importantly, in vitro assays with bone-marrow derived neutrophils confirmed that IL-10 can be induced by these cells by the direct recognition of pneumococcal antigens. In vivo, we identified the recruitment of two neutrophil subpopulations in the lungs following infection, which exhibited clear morphological differences and a distinctive profile of IL-10 production at 48 h post-infection. Furthermore, adoptive transfer of neutrophils from WT mice into IL-10 knockout mice (Il10(-/-) ) fully restored IL-10 production in the lungs and reduced lung histopathology. These results suggest that IL-10 production by neutrophils induced by S. pneumoniae limits lung injury and is important to mediate an effective immune response required for host survival.
- ItemCirculating Endothelial Cells From Septic Shock Patients Convert to Fibroblasts Are Associated With the Resuscitation Fluid Dose and Are Biomarkers for Survival Prediction.(2019) Tapia, Pablo; Gatica, Sebastian; Cortés-Rivera, Cristian; Otero, Carolina; Becerra, Álvaro; Riedel, Claudia A.; Cabello-Verrugio, Claudio; Kalergis, Alexis M.; Simon, FelipeOBJECTIVES:To determine whether circulating endothelial cells from septic shock patients and from nonseptic shock patients are transformed in activated fibroblast by changing the expression level of endothelial and fibrotic proteins, whether the level of the protein expression change is associated with the amount of administered resuscitation fluid, and whether this circulating endothelial cell protein expression change is a biomarker to predict sepsis survival. DESIGN:Prospective study. SETTING:Medical-surgical ICUs in a tertiary care hospital. PATIENTS:Forty-three patients admitted in ICU and 22 healthy volunteers. INTERVENTIONS:None. MEASUREMENTS AND MAIN RESULTS:Circulating mature endothelial cells and circulating endothelial progenitor cells from septic shock and nonseptic shock patients showed evidence of endothelial fibrosis by changing the endothelial protein expression pattern. The endothelial proteins were downregulated, whereas fibroblast-specific markers were increased. The magnitude of the expression change in endothelial and fibrotic proteins was higher in the septic shock nonsurvivors patients but not in nonseptic shock. Interestingly, the decrease in the endothelial protein expression was correlated with the administered resuscitation fluid better than the Acute Physiology and Chronic Health Evaluation II and Sequential Organ Failure Assessment scores in the septic shock nonsurvivors patients but not in nonseptic shock. Notably, the significant difference between endothelial and fibrotic protein expression indicated a nonsurvival outcome in septic shock but not in nonseptic shock patients. Remarkably, area under the receiver operating characteristic curve analysis showed that endothelial protein expression levels predicted the survival outcome better than the Acute Physiology and Chronic Health Evaluation II and Sequential Organ Failure Assessment scores in septic shock but not in nonseptic shock patients. CONCLUSIONS:Circulating endothelial cells from septic shock patients are acutely converted into fibroblasts. Endothelial and fibrotic protein expression level are associated with resuscitation fluid administration magnitude and can be used as biomarkers for an early survival diagnosis of sepsis.
- ItemContribution of autophagy to antiviral immunity(2015) Rey-Jurado, Emma; Riedel, Claudia A.; Gonzalez, Pablo A.; Bueno Ramírez, Susan; Kalergis Parra, Alexis Mikes
- ItemContribution of dendritic cells to the autoimmune pathology of systemic lupus erythematosus(2015) Mackern Oberti, Juan Pablo; Llanos Muñoz, Carolina; Riedel, Claudia A.; Bueno Ramírez, Susan; Kalergis Parra, Alexis Mikes
- ItemDifferential Severe Acute Respiratory Syndrome Coronavirus 2-Specific Humoral Response in Inactivated Virus-Vaccinated, Convalescent, and Breakthrough-Infected Subjects(OXFORD UNIV PRESS INC, 2023) Duarte Peñaloza, Luisa Fernanda; Vazquez Hernandez Yaneisi; Diethelm Varela, Benjamin Manuel; Pavez, Valentina; Berrios-Rojas, Roslye; Riedel, Claudia A.; Mendez, Constanza; White, Jessica A.; Kalergis Parra, Alexis Mikes; Bueno Ramírez, Susan Marcela; González Muñoz, Pablo AlbertoBackground. We sought to identify potential antigens for discerning between humoral responses elicited after vaccination with CoronaVac (a severe acute respiratory syndrome coronavirus 2 [SARS-CoV-2] inactivated vaccine), natural infection, or breakthrough infection., Methods. Serum samples obtained from volunteers immunized with CoronaVac (2 and 3 doses), breakthrough case patients, and from convalescent individuals were analyzed to determine the immunoglobulin (Ig) G responses against 3 structural and 8 nonstructural SARS-CoV-2 antigens., Results. Immunization with CoronaVac induced higher levels of antibodies against the viral membrane (M) protein compared with convalescent subjects both after primary vaccination and after a booster dose. Individuals receiving a booster dose displayed equivalent levels of IgG antibodies against the nucleocapsid (N) protein, similar to convalescent subjects. Breakthrough case patients produced the highest antibody levels against the N and M proteins. Antibodies against nonstructural viral proteins were present in >50% of the convalescent subjects., Conclusions. Vaccinated individuals elicited a different humoral response compared to convalescent subjects. The analysis of particular SARS-CoV-2 antigens could be used as biomarkers for determining infection in subjects previously vaccinated with CoronaVac.
- ItemEfficient Lung Recruitment of Respiratory Syncytial Virus-Specific Th1 Cells Induced by Recombinant Bacillus Calmette-Guerin Promotes Virus Clearance and Protects from Infection(AMER ASSOC IMMUNOLOGISTS, 2010) Cautivo, Kelly M.; Bueno, Susan M.; Cortes, Claudia M.; Wozniak, Aniela; Riedel, Claudia A.; Kalergis, Alexis M.Infection by the respiratory syncytial virus (RSV) can cause extensive inflammation and lung damage in susceptible hosts due to a Th2-biased immune response. Such a deleterious inflammatory response can be enhanced by immunization with formalin- or UV-inactivated RSV, as well as with vaccinia virus expressing the RSV-G protein. Recently, we have shown that vaccination with rBCG-expressing RSV Ags can prevent the disease in the mouse. To further understand the immunological mechanisms responsible for protection against RSV, we have characterized the T cell populations contributing to virus clearance in mice immunized with this BCG-based vaccine. We found that both CD4(+) and CD8(+) T cells were recruited significantly earlier to the lungs of infected mice that were previously vaccinated. Furthermore, we observed that simultaneous adoptive transfer of CD8(+) and CD4(+) RSV-specific T cells from vaccinated mice was required to confer protection against virus infection in naive recipients. In addition, CD4(+) T cells induced by vaccination released IFN-gamma after RSV challenge, indicating that protection is mediated by a Th1 immune response. These data suggest that vaccination with rBCG-expressing RSV Ags can induce a specific effector/memory Th1 immune response consisting on CD4(+) and CD8(+) T cells, both necessary for a fully protective response against RSV. These results support the notion that an effective induction of Th1 T cell immunity against RSV during childhood could counteract the unbalanced Th2-like immune response triggered by the natural RSV infection. The Journal of Immunology, 2010, 185: 7633-7645.
- ItemExcision of an Unstable Pathogenicity Island in Salmonella enterica Serovar Enteritidis Is Induced during Infection of Phagocytic Cells(PUBLIC LIBRARY SCIENCE, 2011) Quiroz, Tania S.; Nieto, Pamela A.; Tobar, Hugo E.; Salazar Echegarai, Francisco J.; Lizana, Rodrigo J.; Quezada, Carolina P.; Santiviago, Carlos A.; Araya, Daniela V.; Riedel, Claudia A.; Kalergis, Alexis M.; Bueno, Susan M.The availability of the complete genome sequence of several Salmonella enterica serovars has revealed the presence of unstable genetic elements in these bacteria, such as pathogenicity islands and prophages. This is the case of Salmonella enterica serovar Enteritidis (S. Enteritidis), a bacterium that causes gastroenteritis in humans and systemic infection in mice. The whole genome sequence analysis for S. Enteritidis unveiled the presence of several genetic regions that are absent in other Salmonella serovars. These regions have been denominated "regions of difference'' (ROD). In this study we show that ROD21, one of such regions, behaves as an unstable pathogenicity island. We observed that ROD21 undergoes spontaneous excision by two independent recombination events, either under laboratory growth conditions or during infection of murine cells. Importantly, we also found that one type of excision occurred at higher rates when S. Enteritidis was residing inside murine phagocytic cells. These data suggest that ROD21 is an unstable pathogenicity island, whose frequency of excision depends on the environmental conditions found inside phagocytic cells.
- ItemExpanding the current knowledge about the role of interleukin-10 to major concerning bacteria(2018) Peñaloza Cerda, Hernán F.; Noguera, Loreani; Riedel, Claudia A.; Bueno Ramírez, Susan
- ItemGene Elements that Regulate Streptococcus pneumoniae Virulence and Immunity Evasion(2013) Nieto Pacheco, Pamela Andrea; Riquelme, Sebastián A.; Riedel, Claudia A.; Kalergis Parra, Alexis Mikes; Bueno Ramírez, Susan
- ItemGenetic and pharmacological modulation of dendritic cell-T cell interactions as a therapeutic strategy for systemic lupus erythematosus.(2011) Llanos, Carolina; Carreno, Leandro J.; Gutierrez, Miguel A.; Riedel, Claudia A.; Jacobelli, Sergio H.; Kalergis, Alexis M.Systemic Lupus Erythematosus (SLE) is a chronic autoimmune disease characterized by an excessive production of auto-antibodies against double-stranded DNA, nucleosomes, ribonucleoproteins and other nuclear components. Accumulation of self-reactive antibodies leads to immune complex deposition in blood vessels, activation of macrophages and complement, inflammation and subsequent tissue damage in several organs, such as the heart, kidneys, lungs and central nervous system. Although significant progress has been made in the past 30 years of research, no effective specific treatments are currently available. The course of this disease remains unpredictable and patients diagnosed with SLE face long-term treatments with the subsequent economic, social and health burden. From the immunological perspective, SLE is a genetic- and environment-controlled disease that involves almost every constituent of the immune system, including both innate and adaptive immunity. Therefore, several immune cell types and molecules could be susceptible for intervention and modulation to develop more effective and specific treatments. More importantly, such therapies are likely not to induce complete immunosuppression and show reduced side effects on patients. In this article we discuss recent work in the field of SLE pathogenesis with a focus on data that provide clues for therapy design and new treatments.
- ItemGestational Hypothyroxinemia Imprints a Switch in the Capacity of Astrocytes and Microglial Cells of the Offspring to React in Inflammation(2018) Opazo, María C.; González, Pablo A.; Flores, Betsi D.; Venegas, Luis F.; Albornoz, Eduardo A.; Cisternas, Pablo; Bohmwald Prieto, Karen; Nieto Pacheco, Pamela Andrea; Bueno Ramírez, Susan; Kalergis Parra, Alexis Mikes; Riedel, Claudia A.
- ItemHormonal Modulation of Dendritic Cells Differentiation, Maturation and Function: Implications for the Initiation and Progress of Systemic Autoimmunity.(2016) Mackern-Oberti, Juan Pablo; Jara, Evelyn L.; Riedel, Claudia A.; Kalergis, Alexis M.Hormonal homeostasis is crucial for keeping a competent and healthy immune function. Several hormones can modulate the function of various immune cells such as dendritic cells (DCs) by influencing the initiation of the immune response and the maintenance of peripheral tolerance to self-antigens. Hormones, such as estrogens, prolactin, progesterone and glucocorticoids may profoundly affect DCs differentiation, maturation and function leading to either a pro-inflammatory or an anti-inflammatory (or tolerogenic) phenotype. If not properly regulated, these processes can contribute to the pathogenesis of autoimmune disease. An unbalanced hormonal status may affect the production of pro-inflammatory cytokines, the expression of activating/inhibitory receptors and co-stimulatory molecules on conventional and plasmacytoid DCs (pDCs), conferring susceptibility to develop autoimmunity. Estrogen receptor (ER)-α signaling in conventional DCs can promote IFN-α and IL-6 production and induce the expression of CD40, CD86 and MHCII molecules. Furthermore, estrogen modulates the pDCs response to Toll-like receptor ligands enhancing T cell priming. During lupus pathogenesis, ER-α deficiency decreased the expression of MHC II on pDCs from the spleen. In contrast, estradiol administration to lupus-prone female mice increased the expression of co-stimulatory molecules, enhanced the immunogenicity and produced large amounts of IL-6, IL-12 and TNF-α by bone marrow-derived DCs. These data suggest that estradiol/ER signaling may play an active role during lupus pathology. Similarly, understanding hormonal modulation of DCs may favor the design of new therapeutic strategies based on autologous tolerogenic DCs transfer, especially in sex-biased systemic autoimmune diseases. In this review, we discuss recent data relative to the role of different hormones (estrogen, prolactin, progesterone and glucocorticoids) in DC function during systemic autoimmune pathogenesis.
- ItemHost immunity during RSV pathogenesis(2008) Bueno Ramírez, Susan; González Muñoz, Pablo Alberto; Pacheco, Rodrigo; Leiva Llantén, Eduardo David; Cautivo Reyes, Kelly Margarita; Tobar Durán, Hugo Eduardo; Mora, Jorge E.; Prado, Carolina E.; Zuniga, Juan P.; Jimenez, Jorge; Riedel, Claudia A.; Kalergis Parra, Alexis Mikes
- ItemHuman Respiratory Syncytial Virus: Infection and Pathology(2016) Bohmwald Prieto, Karen; Espinoza Véliz, Janyra Alejandra; Rey Jurado, Emma; Gómez Johnson, Roberto Sebastian; González Muñoz, Pablo Alberto; Bueno Ramírez, Susan; Riedel, Claudia A.; Kalergis Parra, Alexis MikesThe human respiratory syncytial virus (hRSV) is by far the major cause of acute lower respiratory tract infections (ALRTIs) worldwide in infants and children younger than 2 years. The overwhelming number of hospitalizations due to hRSV-induced ALRTI each year is due, at least in part, to the lack of licensed vaccines against this virus. Thus, hRSV infection is considered a major public health problem and economic burden in most countries. The lung pathology developed in hRSV-infected individuals is characterized by an exacerbated proinflammatory and unbalanced Th2-type immune response. In addition to the adverse effects in airway tissues, hRSV infection can also cause neurologic manifestations in the host, such as seizures and encephalopathy. Although the origins of these extrapulmonary symptoms remain unclear, studies with patients suffering from neurological alterations suggest an involvement of the inflammatory response against hRSV. Furthermore, hRSV has evolved numerous mechanisms to modulate and evade the immune response in the host. Several studies have focused on elucidating the interactions between hRSV virulence factors and the host immune system, to rationally design new vaccines and therapies against this virus. Here, we discuss about the infection, pathology, and immune response triggered by hRSV in the host.
- ItemHypothyroidism in the Adult Rat Causes Incremental Changes in Brain-Derived Neurotrophic Factor, Neuronal and Astrocyte Apoptosis, Gliosis, and Deterioration of Postsynaptic Density(MARY ANN LIEBERT, INC, 2012) Cortes, Claudia; Eugenin, Eliseo; Aliaga, Esteban; Carreno, Leandro J.; Bueno, Susan M.; Gonzalez, Pablo A.; Gayol, Silvina; Naranjo, David; Noches, Veronica; Marassi, Michelle P.; Rosenthal, Doris; Jadue, Cindy; Ibarra, Paula; Keitel, Cecilia; Wohllk, Nelson; Court, Felipe; Kalergis, Alexis M.; Riedel, Claudia A.Background: Adult hypothyroidism is a highly prevalent condition that impairs processes, such as learning and memory. Even though tetra-iodothyronine (T-4) treatment can overcome the hypothyroidism in the majority of cases, it cannot fully recover the patient's learning capacity and memory. In this work, we analyzed the cellular and molecular changes in the adult brain occurring with the development of experimental hypothyroidism.
- ItemIdentification of biomarkers for disease severity in nasopharyngeal secretions of infants with upper or lower respiratory tract viral infectionsBertrand N., Pablo; Vazquez, Yaneisi; Beckhaus, Andrea A.; González Carreño, Liliana Andrea; Contreras Sepúlveda, Ana María; Ferrés Garrido, Marcela Viviana; Padilla Pérez, Oslando; Riedel, Claudia A.; Kalergis Parra, Alexis Mikes; Bueno, Susan M.Lower respiratory tract infections (LRTIs) produced by viruses are the most frequent cause of morbidity and mortality in children younger than 5 years of age. The immune response triggered by viral infection can induce a strong inflammation in the airways and cytokines could be considered as biomarkers for disease severity as these molecules modulate the inflammatory response that defines the outcome of patients. Aiming to predict the severity of disease during respiratory tract infections, we conducted a 1-year follow-up observational study in infants who presented upper or lower respiratory tract infections caused by seasonal respiratory viruses. At the time of enrollment, nasopharyngeal swabs (NPS) were obtained from infants to measure mRNA expression and protein levels of IL-3, IL-8, IL-33, and thymic stromal lymphopoietin. While all cytokines significantly increased their protein levels in infants with upper and lower respiratory tract infections as compared to control infants, IL-33 and IL-8 showed a significant increase in respiratory syncytial virus (RSV)-infected patients with LRTI as compared to patients with upper respiratory tract infection. We also found higher viral loads of RSV-positive samples with a greater IL-8 response at the beginning of the symptoms. Data obtained in this study suggest that both IL-8 and IL-33 could be used as biomarkers for clinical severity for infants suffering from LRTIs caused by the RSV.
- ItemInduction of Tolerogenic Dendritic Cells by NF-κB Blockade and Fcγ Receptor Modulation(2011) Carreño, Leandro J.; Riedel, Claudia A.; Kalergis, Alexis M.Autoimmune diseases develop as a result of an unbalanced adaptive immunity that targets self-antigens and causes destruction of healthy host tissues. Maintenance of peripheral immune tolerance to self- antigens is mainly mediated by dendritic cells (DCs), professional antigen-presenting cells that modulate the activation of T cells. Due to their key role as regulators of adaptive immunity, identification of means of enhancing DC tolerogenic capacity and therapeutic potential is a priority goal to reduce autoimmune disease burden in an antigen-specific manner. Our findings suggest novel approaches to enhance DC capacity to induce self-tolerance and reduce the severity of autoimmune disorders. Specifically, we have shown, both in vitro and in vivo, that NF-κB blockade on DCs by andrographolide or rosiglitazone can significantly enhance the tolerogenic capacity of DCs. Furthermore, we have observed that expression ratio of the activating FcγRIII or the inhibitory FcγRIIb is determinant for the tolerogenic potential of DCs. In this chapter, we describe the procedures to produce tolerogenic DCs and explain the potential therapeutic use of two NF-κB inhibitors for the treatment of autoimmune disease models, such as experimental autoimmune encephalomyelitis (EAE) and systemic lupus erythematosus (SLE) in mice. Therefore, our studies support the notion that FcγRs and NF-κB can be considered as pharmacological targets to increase the capacity of DCs to induce or restore self-tolerance and decrease inflammatory damage to self-tissues.