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Metastasis is a cancer-related systemic disease and is responsible for the greatest mortality rate among cancer patients. Interestingly, the interaction between the immune system and cancer cells seems to play a key role in metastasis formation in the target organ. However, this complex network is only partially understood. We previously found that IL-22 produced by tissue resident iNKT17 cells promotes cancer cell extravasation, the early step of metastasis. Based on these data, we aimed here to decipher the role of IL-22 in the last step of metastasis formation. We found that IL-22 levels were increased in established metastatic sites in both human and mouse. We also found that Th22 cells were the key source of IL-22 in established metastasis sites, and that deletion of IL-22 in CD4+ T cells was protective in liver metastasis formation. Accordingly, the administration of a murine IL-22 neutralizing antibody in the establishment of metastasis formation significantly reduced the metastatic burden in a mouse model. Mechanistically, IL-22-producing Th22 cells promoted angiogenesis in established metastasis sites. In conclusion, our findings highlight that IL-22 is equally as important in contributing to metastasis formation at late metastatic stages, and thus, identify it as a novel therapeutic target in established metastasis.
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Linfocitos T CD4-Positivos , Neoplasias Hepáticas , Humanos , Animales , Ratones , Interleucinas , Interleucina-22RESUMEN
Background: The immune system plays a pivotal role in cancer progression. Interleukin 22 binding protein (IL-22BP), a natural antagonist of the cytokine interleukin 22 (IL-22) has been shown to control the progression of colorectal cancer (CRC). However, the role of IL-22BP in the process of metastasis formation remains unknown. Methods: We used two different murine in vivo metastasis models using the MC38 and LLC cancer cell lines and studied lung and liver metastasis formation after intracaecal or intrasplenic injection of cancer cells. Furthermore, IL22BP expression was measured in a clinical cohort of CRC patients and correlated with metastatic tumor stages. Results: Our data indicate that low levels of IL-22BP are associated with advanced (metastatic) tumor stages in colorectal cancer. Using two different murine in vivo models we show that IL-22BP indeed controls the progression of liver but not lung metastasis in mice. Conclusions: We here demonstrate a crucial role of IL-22BP in controlling metastasis progression. Thus, IL-22 might represent a future therapeutic target against the progression of metastatic CRC.
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Intestinal epithelial cells play important roles in the absorption of nutrients, secretion of electrolytes and food digestion. The function of these cells is strongly influenced by purinergic signalling activated by extracellular ATP (eATP) and other nucleotides. The activity of several ecto-enzymes determines the dynamic regulation of eATP. In pathological contexts, eATP may act as a danger signal controlling a variety of purinergic responses aimed at defending the organism from pathogens present in the intestinal lumen. In this study, we characterized the dynamics of eATP on polarized and non-polarized Caco-2 cells. eATP was quantified by luminometry using the luciferin-luciferase reaction. Results show that non-polarized Caco-2 cells triggered a strong but transient release of intracellular ATP after hypotonic stimuli, leading to low micromolar eATP accumulation. Subsequent eATP hydrolysis mainly determined eATP decay, though this effect could be counterbalanced by eATP synthesis by ecto-kinases kinetically characterized in this study. In polarized Caco-2 cells, eATP showed a faster turnover at the apical vs the basolateral side. To quantify the extent to which different processes contribute to eATP regulation, we created a data-driven mathematical model of the metabolism of extracellular nucleotides. Model simulations showed that eATP recycling by ecto-AK is more efficient a low micromolar eADP concentrations and is favored by the low eADPase activity of Caco-2 cells. Simulations also indicated that a transient eATP increase could be observed upon the addition of non-adenine nucleotides due the high ecto-NDPK activity in these cells. Model parameters showed that ecto-kinases are asymmetrically distributed upon polarization, with the apical side having activity levels generally greater in comparison with the basolateral side or the non-polarized cells. Finally, experiments using human intestinal epithelial cells confirmed the presence of functional ecto-kinases promoting eATP synthesis. The adaptive value of eATP regulation and purinergic signalling in the intestine is discussed.
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Adenosina Trifosfato , Células Epiteliales , Humanos , Adenosina Trifosfato/metabolismo , Células CACO-2 , Células Epiteliales/metabolismo , Proteínas de Transferencia de FosfolípidosRESUMEN
New antiviral treatments are needed to deal with the unpredictable emergence of viruses. Furthermore, vaccines and antivirals are only available for just a few viral infections, and antiviral drug resistance is an increasing concern. Cyanidin (a natural product also called A18), a key flavonoid that is present in red berries and other fruits, attenuates the development of several diseases, through its anti-inflammatory effects. Regarding its mechanism of action, A18 was identified as an IL-17A inhibitor, resulting in the attenuation of IL-17A signaling and associated diseases in mice. Importantly, A18 also inhibits the NF-κB signaling pathway in different cell types and conditions in vitro and in vivo. In this study, we report that A18 restricts RSV, HSV-1, canine coronavirus, and SARS-CoV-2 multiplication, indicating a broad-spectrum antiviral activity. We also found that A18 can control cytokine and NF-κB induction in RSV-infected cells independently of its antiviral activity. Furthermore, in mice infected with RSV, A18 not only significantly reduces viral titers in the lungs, but also diminishes lung injury. Thus, these results provide evidence that A18 could be used as a broad-spectrum antiviral and may contribute to the development of novel therapeutic targets to control these viral infections and pathogenesis.
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Antivirales , COVID-19 , Ratones , Animales , Antivirales/farmacología , Antivirales/uso terapéutico , SARS-CoV-2/metabolismo , FN-kappa B/metabolismo , Interleucina-17 , Flavonoides/farmacologíaRESUMEN
OBJECTIVE: We aimed to assess whether native spleen preservation during visceral transplantation (VT) affects graft-versus-host-disease (GVHD) incidence. SUMMARY BACKGROUND DATA: GVHD is one of the most severe and frequently lethal hematological complications after VT procedures. Because there is no specific treatment for GVHD, it is imperative to develop a strategy to reduce donor lymphocyte engraftment and proliferation. METHODS: Our study included both clinical and experimental data. A total of 108 patients were divided into 3 groups: a native spleen preservation group, a native spleen removal with no donor spleen group, and a donor spleen included (allogeneic spleen) group. We also used an allogeneic VT rat model, in which recipients were divided into 2 groups: a native spleen preservation (+SP) group and a native spleen removal (-S) group. Skin rash appearance, histopathological changes, chimerism, and spleen effects on circulating allogeneic T-cells were assessed. RESULTS: The patients with native spleen preservation showed a lower rate of GVHD ( P <.001) and better survival ( P <.05) than those in the other groups. Skin and histological signs of GVHD were lower in the rats in the +SP group ( P <.05). The donor T-cell frequency in the bloodstream and skin was also significantly reduced when the native spleen was preserved ( P <.01 and P <.0001, respectively). CONCLUSIONS: The clinical and experimental data indicate that recipient spleen preservation protects against GVHD after VT, and donor cell clearance from the bloodstream by spleen macrophages could be the underlying mechanism. Therefore, spleen preservation should be considered in VT procedures, whenever possible.
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Trasplante de Médula Ósea , Enfermedad Injerto contra Huésped , Ratas , Animales , Ratones , Bazo , Trasplante Homólogo , Linfocitos T , Ratones Endogámicos C57BLRESUMEN
OBJECTIVES: Immunosuppressive strategies for intestinal transplant have changed over time. However, specific intestinal transplant-oriented protocols and reports on long-term maintenance regimens are scarce. Our objective was to evaluate the impact of 2 different initial immunosuppressive protocols based on thymoglobulin (group A) and basiliximab (anti-interleukin 2 antibody) (group B) and of changes to maintenance immunosuppression over long-term follow-up in intestinal transplant recipients. MATERIALS AND METHODS: We performed a retrospective analysis of a prospectively established protocol for intestinal transplant immunosuppression, conducted between May 2006 and December 2020. We analyzed 51 intestinal transplant recipients, with 6 patients excluded because of early death or graft loss. Acute cellular rejection frequency and grade, number of acute cellular rejection episodes, time to the first acute cellular rejection episode, response to treatment, number of patients who progressed to chronic allograft rejection, kidney function, infections, incidence of posttransplant lymphoproliferative disorder and graft-versus-host disease, and patient and graft survival were analyzed. RESULTS: In the study groups, there were 87 acute cellular rejection episodes in 45 patients (33 in group A and 54 in group B). We found degree of acute cellular rejection to be mild in 45 patients, moderate in 18, and severe in 24 (not significant between groups). Our comparison of induction therapy (thymoglobulin [group A] vs interleukin 2 antibody [group B]) did not show any statistical difference during clinical followup. Long-term review showed that all patients were on tacrolimus. Five-year patient and graft survival rates were 62% and 45% for group A and 54% and 46% for group B, respectively (not significant). CONCLUSIONS: Long-term patient and graft outcomes reflected the use of an individualized follow-up with adjustments and changes in immunosuppressive medications according to the patient's clinical course and complications rather than based on the induction immunosuppressive protocol used.
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Anticuerpos Monoclonales , Trasplante de Riñón , Humanos , Supervivencia de Injerto , Estudios Retrospectivos , Trasplante de Riñón/efectos adversos , Inmunosupresores/efectos adversos , Terapia de Inmunosupresión/métodos , Rechazo de Injerto/tratamiento farmacológicoRESUMEN
BACKGROUND: Type III Intestinal Failure (IF) is a devastating clinical condition.characterized by the inability of the gut to absorb necessary macronutrients, and/or water and electrolytes, requiring Parenteral Nutrition (PN) as chronic therapy. Long-term PN may lead to life-threatening complications; the loss of central venous access (LCVA) is the most frequent and challenging. To date, few studies in the literature have reported the relevance of Non-conventional Vascular Accesses (NCVA) in the management IF as part of the comprehensive multidisciplinary care. METHODS: A retrospective analysis of a database collected from January 2006 to December 2019 was performed using SPSS v25.0 for statistical analysis, followed by a systematic review, using the PRISMA.methodology RESULTS: From January 2006 to December 2019, 184 NCVA were placed in 71 patients with LCVA as IF-related complication; 173 were placed in 61 patients by interventional radiology (IR) and 11 NCVA were placed in 10 patients by the surgical team during the intestinal transplant (ITx) operation. From the 173 IR procedures 166 (95.9%) were successful with 3 ± 2.7 procedures/patient; average catheter permanence rate was 738.68 ± 997 days; complications related to the procedures occurred in 18/173 (10.4%), including two deaths. On the other hand, among the 11 NCVA implanted by the surgical team, 7 (64%) were successful and were safely withdrawn 30 days after ITx when were no longer needed; 2 (18%) catheters malfunctioned during the first week and could not be further used, and 1 was accidently removed; average catheter permanence rate was 26 ± 4 days. There was one complication (9%) requiring laparotomy; there was no mortality associated the procedure in this group. A systematic review was conducted to evaluate the success and safety of NCVA as part of the treatment of HPN-related complications; from 337,542 papers, 14 studies were included. A total of 28 HPN-patients with LCVA received NCVA; 34 procedures were successfully performed, while procedure-related complications were reported in 11.7%, as well as one death. CONCLUSIONS: The data analyzed show that NCVAs may be successfully placed by expert teams, allowing to sustain long-term PN, as well as increasing the Intestinal Transplantation applicability for candidates in the extreme need of vascular access.
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Síndrome de la Vena Cava Superior , Humanos , Nutrición Parenteral Total , Estudios RetrospectivosRESUMEN
CYP121 of Mycobacterium tuberculosis (Mtb) is an essential target for the development of novel potent drugs against tuberculosis (TB). Besides known antifungal azoles, further compounds of the azole class were recently identified as CYP121 inhibitors with antimycobacterial activity. Herein, we report the screening of a similarity-oriented library based on the former hit compound, the evaluation of affinity toward CYP121, and activity against M. bovis BCG. The results enabled a comprehensive SAR study, which was extended through the synthesis of promising compounds and led to the identification of favorable features for affinity and/or activity and hit compounds with 2.7-fold improved potency. Mode of action studies show that the hit compounds inhibit substrate conversion and highlighted CYP121 as the main antimycobacterial target of our compounds. Exemplified complex crystal structures of CYP121 with three inhibitors reveal a common binding site. Engaging in both hydrophobic interactions as well as hydrogen bonding to the sixth iron ligand, our compounds block a solvent channel leading to the active site heme. Additionally, we report the first CYP inhibitors that are able to reduce the intracellular replication of M. bovis BCG in macrophages, emphasizing their potential as future drug candidates against TB.
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Antituberculosos/farmacología , Inhibidores Enzimáticos del Citocromo P-450/farmacología , Imidazoles/farmacología , Mycobacterium tuberculosis/efectos de los fármacos , Bibliotecas de Moléculas Pequeñas/farmacología , Antituberculosos/síntesis química , Antituberculosos/química , Inhibidores Enzimáticos del Citocromo P-450/síntesis química , Inhibidores Enzimáticos del Citocromo P-450/química , Sistema Enzimático del Citocromo P-450 , Relación Dosis-Respuesta a Droga , Imidazoles/síntesis química , Imidazoles/química , Pruebas de Sensibilidad Microbiana , Estructura Molecular , Mycobacterium tuberculosis/enzimología , Bibliotecas de Moléculas Pequeñas/síntesis química , Bibliotecas de Moléculas Pequeñas/química , Relación Estructura-ActividadRESUMEN
BACKGROUND: The main targets of the host's immune system in Trichinella spiralis infection are the adult worms (AW), at the gut level, and the migrant or newborn larvae (NBL), at systemic and pulmonary levels. Most of the studies carried out in the gut mucosa have been performed on the Payer's patches and/or the mesenteric lymph nodes but not on the lamina propria, therefore, knowledge on the gut immune response against T. spiralis remains incomplete. METHODS: This study aimed at characterizing the early mucosal immune response against T. spiralis, particularly, the events taking place between 1 and 13 dpi. For this purpose, Wistar rats were orally infected with muscle larvae of T. spiralis and the humoral and cellular parameters of the gut immunity were analysed, including the evaluation of the ADCC mechanism exerted by lamina propria cells. RESULTS: A marked inflammation and structural alteration of the mucosa was found. The changes involved an increase in goblet cells, eosinophils and mast cells, and B and T lymphocytes, initially displaying a Th1 profile, characterised by the secretion of IFN-γ and IL-12, followed by a polarization towards a Th2 profile, with a marked increase in IgE, IgG1, IL-4, IL-5 and IL-13 levels, which occurred once the infection was established. In addition, the helminthotoxic activity of lamina propria cells demonstrated the role of the intestine as a place of migrant larvae destruction, indicating that not all the NBLs released in the gut will be able to reach the muscles. CONCLUSIONS: The characterization of the immune response triggered in the gut mucosa during T. spiralis infection showed that not only an effector mechanism is directed toward the AW but also towards the NBL as a cytotoxic activity was observed against NBL exerted by lamina propria cells.
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Inmunidad Mucosa , Trichinella spiralis/inmunología , Animales , Anticuerpos Antihelmínticos , Antígenos Helmínticos , Citocinas/metabolismo , Inmunidad Innata , Inflamación/parasitología , Mucosa Intestinal/inmunología , Larva/inmunología , Mastocitos , Ratas , Ratas Wistar/parasitología , Linfocitos T , Triquinelosis/inmunologíaRESUMEN
Respiratory syncytial virus (RSV) is a leading cause of lower respiratory tract disease and bronchiolitis in children, as well as an important cause of morbidity and mortality in elderly and immunocompromised individuals. However, there is no safe and efficacious RSV vaccine or antiviral treatment. Toll Like Receptors (TLR) are important molecular mediators linking innate and adaptive immunity, and their stimulation by cognate agonists has been explored as antiviral agents. Imiquimod is known as a TLR7 agonist, but additionally acts as an antagonist for adenosine receptors. In this study, we demonstrate that imiquimod, but not resiquimod, has direct anti-RSV activity via PKA pathway in HEp-2 and A549 cells, independently of an innate response. Imiquimod restricts RSV infection after viral entry into the host cell, interfering with viral RNA and protein synthesis. Probably as a consequence of these anti-RSV properties, imiquimod displays cytokine modulating activity in RSV infected epithelial cells. Moreover, in a murine model of RSV infection, imiquimod treatment improves the course of acute disease, evidenced by decreased weight loss, reduced RSV lung titers, and attenuated airway inflammation. Consequently, imiquimod represents a promising therapeutic alternative against RSV infection and may inform the development of novel therapeutic targets to control RSV pathogenesis.
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Antivirales/uso terapéutico , Imiquimod/uso terapéutico , Inflamación/tratamiento farmacológico , Infecciones por Virus Sincitial Respiratorio/inmunología , Transducción de Señal , Replicación Viral/efectos de los fármacos , Células A549 , Animales , Línea Celular Tumoral , Proteínas Quinasas Dependientes de AMP Cíclico/metabolismo , Citocinas/antagonistas & inhibidores , Citocinas/inmunología , Modelos Animales de Enfermedad , Células Epiteliales/efectos de los fármacos , Células Epiteliales/inmunología , Células Epiteliales/virología , Femenino , Humanos , Inflamación/virología , Pulmón/efectos de los fármacos , Pulmón/virología , Ratones , Ratones Endogámicos BALB C , Infecciones por Virus Sincitial Respiratorio/tratamiento farmacológico , Virus Sincitial Respiratorio Humano/efectos de los fármacos , Virus Sincitial Respiratorio Humano/fisiología , Carga ViralRESUMEN
Brucella abortus stimulates an inflammatory immune response that stimulates the endocrine system, inducing the secretion of dehydroepiandrosterone (DHEA) and cortisol. In humans, the active disease is generally present as osteoarticular brucellosis. In previous studies we showed that B. abortus infection of synoviocytes creates a proinflammatory microenvironment. We proposed to determine the role of cortisol and DHEA on synoviocytes and infiltrating monocytes during B. abortus infection. Cortisol inhibited IL-6, IL-8, MCP-1, and MMP-2 secretion induced by B. abortus infection in synovial fibroblast. Cortisol-mediated MMP-2 inhibition during B. abortus infection was reversed by IL-6. DHEA inhibited B. abortus-induced RANKL up-regulation in synovial fibroblast through estrogen receptor (ER). B. abortus infection did not modulate glucocorticoid receptor (GR) expression. Cell responses to cortisol also depended on its intracellular bioavailability, according to the activity of the isoenzymes 11ß-hydroxysteroid dehydrogenase (HSD) type-1 and 11ß-HSD2 (which are involved in cortisone-cortisol interconversion). B. abortus infection did not modify 11ß-HSD1 expression and GRα/ß ratio in the presence or absence of adrenal steroids. Supernatants from B. abortus-infected monocytes induced 11ß-HSD1 in synovial cells. Administration of cortisone was capable of inhibiting the secretion of RANKL by synoviocytes mimicking cortisol's effect. These results go along with previous observations that highlighted the ability of synovial tissue to secrete active steroids, making it an intracrine tissue. This is the first study that contributes to the knowledge of the consequence of adrenal steroids on synoviocytes in the context of a bacterial infection.
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Respiratory syncytial virus (RSV) is a leading cause of lower respiratory tract disease and bronchiolitis in children worldwide. No vaccine or specific, effective treatment is currently available. ß-escin is one of the main bioactive constituents of Aesculus hippocastanum L. (Hippocastanaceae) seed extract (AH), and both ß-escin and AH have demonstrated a beneficial role in clinical therapy because of their anti-edematous, anti-inflammatory and antioxidative effects. Besides, we have reported that ß-escin and AH show virucidal, antiviral and immunomodulatory activities against the enveloped viruses HSV-1, VSV and Dengue virus in vitro. In this study, we demonstrate that ß-escin and AH have virucidal and antiviral activities against RSV, as well as NF-κB, AP-1 and cytokine modulating activities in RSV infected epithelial and macrophage cell lines in vitro. Besides, in a murine model of pulmonary RSV infection, AH treatment improves the course of acute disease, evidenced by decreased weight loss, reduced RSV lung titers, and attenuated airway inflammation. In contrast, even though ß-escin showed, similarly to AH, antiviral and immunomodulatory properties in vitro, it neither reduces viral titers nor attenuates lung injury in vivo. Thus, our data demonstrate that AH restrains RSV disease through antiviral and immunomodulatory effect.
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Aesculus/química , Antivirales/uso terapéutico , Extractos Vegetales/farmacología , Neumonía/tratamiento farmacológico , Infecciones por Virus Sincitial Respiratorio/tratamiento farmacológico , Virus Sincitial Respiratorio Humano/efectos de los fármacos , Animales , Línea Celular , Femenino , Humanos , Inmunomodulación , Pulmón/efectos de los fármacos , Pulmón/patología , Pulmón/virología , Ratones , Ratones Endogámicos BALB C , Plantas Medicinales/química , Neumonía/virología , Semillas/químicaRESUMEN
Osteoarticular brucellosis is the most common localization of human active disease. Osteoblasts are specialized mesenchymal-derived cells involved in bone formation and are considered as professional mineralizing cells. Autophagy has been involved in osteoblast metabolism. The present study demonstrates that Brucella abortus infection induces the activation of the autophagic pathway in osteoblast cells. Autophagy was revealed by upregulation of LC3II/LC3I ratio and Beclin-1 expression as well as inhibition of p62 expression in infected cells. Induction of autophagy was also corroborated by using the pharmacological inhibitors wortmannin, a PI 3-kinase inhibitor, and leupeptin plus E64 (inhibitors of lysosomal proteases). Autophagy induction create a microenvironment that modifies osteoblast metabolism by the inhibition of the deposition of organic and mineral matrix, the induction of matrix metalloproteinase (MMP)-2, osteopontin, and RANKL secretion leading to bone loss. Accordingly, autophagy is also involved in the down-modulation of the master transcription factor in bone formation osterix during B. abortus infection. Taking together our results indicate that B. abortus induces the activation of autophagy pathway in osteoblast cells and this activation is involved in the modulation of osteoblast function and bone formation.
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Autofagia , Brucella abortus/patogenicidad , Brucelosis , Osteoblastos/metabolismo , Osteoblastos/microbiología , Beclina-1/metabolismo , Matriz Ósea/metabolismo , Matriz Ósea/microbiología , Brucelosis/patología , Diferenciación Celular , Línea Celular , Colágeno/metabolismo , Citocinas/metabolismo , Humanos , Metaloproteinasa 2 de la Matriz/metabolismo , Proteínas Asociadas a Microtúbulos/metabolismo , Osteogénesis , Osteopontina , Fosfatidilinositol 3-Quinasas , Ligando RANK/metabolismo , Proteínas de Unión al ARN/metabolismoRESUMEN
Tuberculosis remains a major global health problem and efforts to develop a more effective vaccine have been unsuccessful so far. Targeting antigens (Ags) to dendritic cells (DCs) in vivo has emerged as a new promising vaccine strategy. In this approach, Ags are delivered directly to DCs via antibodies that bind to endocytic cell-surface receptors. Here, we explored DC-specific-ICAM3-grabbing-nonintegrin (DC-SIGN) targeting as a potential vaccine against tuberculosis. For this, we made use of the hSIGN mouse model that expresses human DC-SIGN under the control of the murine CD11c promoter. We show that in vitro and in vivo delivery of anti-DC-SIGN antibodies conjugated to Ag85B and peptide 25 of Ag85B in combination with anti-CD40, the fungal cell wall component zymosan, and the cholera toxin-derived fusion protein CTA1-DD induces strong Ag-specific CD4+ T-cell responses. Improved anti-mycobacterial immunity was accompanied by increased frequencies of Ag-specific IFN-γ+ IL-2+ TNF-α+ polyfunctional CD4+ T cells in vaccinated mice compared with controls. Taken together, in this study we provide the proof of concept that the human DC-SIGN receptor can be efficiently exploited for vaccine purposes to promote immunity against mycobacterial infections.
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Antígenos Bacterianos/inmunología , Moléculas de Adhesión Celular/inmunología , Células Dendríticas/inmunología , Inmunidad Celular , Lectinas Tipo C/inmunología , Mycobacterium tuberculosis/inmunología , Receptores de Superficie Celular/inmunología , Células TH1/inmunología , Vacunas contra la Tuberculosis/inmunología , Animales , Citocinas/inmunología , Células Dendríticas/patología , Humanos , Ratones , Células TH1/patología , Tuberculosis/inmunología , Tuberculosis/prevención & controlRESUMEN
Brucella abortus induces an inflammatory response that stimulates the endocrine system resulting in the secretion of cortisol and dehydroepiandrosterone (DHEA). Osteoarticular brucellosis is the most common presentation of the active disease in humans, and we have previously demonstrated that B. abortus infection inhibits osteoblast function. We aimed to evaluate the role of cortisol and DHEA on osteoblast during B. abortus infection. B. abortus infection induces apoptosis and inhibits osteoblast function. DHEA treatment reversed the effect of B. abortus infection on osteoblast by increasing their proliferation, inhibiting osteoblast apoptosis, and reversing the inhibitory effect of B. abortus on osteoblast differentiation and function. By contrast, cortisol increased the effect of B. abortus infection. Cortisol regulates target genes by binding to the glucocorticoid receptor (GR). B. abortus infection inhibited GRα expression. Cell responses to cortisol not only depend on GR expression but also on its intracellular bioavailability, that is, dependent on the activity of the isoenzymes 11ß-hydroxysteroid dehydrogenase (HSD) type-1, 11ß-HSD2 (which convert cortisone to cortisol and vice versa, respectively). Alterations in the expression of these isoenzymes in bone cells are associated with bone loss. B. abortus infection increased 11ß-HSD1 expression but had no effect on 11ß-HSD2. DHEA reversed the inhibitory effect induced by B. abortus infection on osteoblast matrix deposition in an estrogen receptor- and ERK1/2-dependent manner. We conclude that DHEA intervention improves osteoblast function during B. abortus infection making it a potential candidate to ameliorate the osteoarticular symptoms of brucellosis.
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Brucella abortus/fisiología , Brucelosis Bovina/metabolismo , Brucelosis Bovina/microbiología , Deshidroepiandrosterona/metabolismo , Proteína Quinasa 1 Activada por Mitógenos/metabolismo , Proteína Quinasa 3 Activada por Mitógenos/metabolismo , Osteoblastos/metabolismo , Receptores de Estrógenos/metabolismo , Animales , Apoptosis , Biomarcadores , Brucelosis Bovina/genética , Brucelosis Bovina/patología , Bovinos , Diferenciación Celular , Línea Celular , Proliferación Celular , Expresión Génica , Ratones , Viabilidad Microbiana , Osteoblastos/citología , Osteogénesis/efectos de los fármacos , Receptores de Glucocorticoides/genética , Receptores de Glucocorticoides/metabolismoRESUMEN
Osteoarticular brucellosis is the most common localization of human active disease. Osteocytes are the most abundant cells of bone. They secrete factors that regulate the differentiation of both osteoblasts and osteoclasts during bone remodeling. The aim of this study is to determine if Brucella abortus infection modifies osteocyte function. Our results indicate that B. abortus infection induced matrix metalloproteinase 2 (MMP-2), receptor activator for NF-κB ligand (RANKL), proinflammatory cytokines, and keratinocyte chemoattractant (KC) secretion by osteocytes. In addition, supernatants from B. abortus-infected osteocytes induced bone marrow-derived monocytes (BMM) to undergo osteoclastogenesis. Using neutralizing antibodies against tumor necrosis factor alpha (TNF-α) or osteoprotegerin (OPG), RANKL's decoy receptor, we determined that TNF-α and RANKL are involved in osteoclastogenesis induced by supernatants from B. abortus-infected osteocytes. Connexin 43 (Cx43) and the integrins E11/gp38, integrin-α, integrin-ß, and CD44 are involved in cell-cell interactions necessary for osteocyte survival. B. abortus infection inhibited the expression of Cx43 but did not modify the expression of integrins. Yet the expression of both Cx43 and integrins was inhibited by supernatants from B. abortus-infected macrophages. B. abortus infection was not capable of inducing osteocyte apoptosis. However, supernatants from B. abortus-infected macrophages induced osteocyte apoptosis in a dose-dependent manner. Taken together, our results indicate that B. abortus infection could alter osteocyte function, contributing to bone damage.
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Brucella abortus/patogenicidad , Conexina 43/biosíntesis , Integrinas/biosíntesis , Osteocitos/metabolismo , Ligando RANK/metabolismo , Factor de Necrosis Tumoral alfa/metabolismo , Animales , Apoptosis , Brucelosis/microbiología , Brucelosis/patología , Diferenciación Celular , Línea Celular , Quimiocina CXCL1/metabolismo , Macrófagos/microbiología , Metaloproteinasa 2 de la Matriz/metabolismo , Ratones , Osteoclastos/citología , Osteocitos/microbiología , Osteoprotegerina/inmunología , Factor de Necrosis Tumoral alfa/inmunologíaRESUMEN
Probiotics can modulate the immune system, conferring beneficial effects on the host. Understanding how these microorganisms contribute to improve the health status is still a challenge. Previously, we have demonstrated that Enterococcus faecalis CECT7121 implants itself and persists in the murine gastrointestinal tract, and enhances and skews the profile of cytokines towards the Th1 phenotype in several biological models. Given the importance of dendritic cells (DCs) in the orchestration of immunity, the aim of this work was to elucidate the influence of E. faecalis CECT7121 on DCs and the outcome of the immune responses. In this work we show that E. faecalis CECT7121 induces a strong dose-dependent activation of DCs and secretion of high levels of IL-12, IL-6, TNFα, and IL-10. This stimulation is dependent on TLR signaling, and skews the activation of T cells towards the production of IFNγ. The influence of this activation in the establishment of Th responses in vivo shows the accumulation of specific IFNγ-producing cells. Our findings indicate that the activation exerted by E. faecalis CECT7121 on DCs and its consequence on the cellular adaptive immune response may have broad therapeutic implications in immunomodulation.
Asunto(s)
Células Dendríticas/efectos de los fármacos , Células Dendríticas/inmunología , Enterococcus faecalis/inmunología , Inmunomodulación/efectos de los fármacos , Inmunomodulación/inmunología , Interferón gamma/inmunología , Probióticos/administración & dosificación , Animales , Tracto Gastrointestinal/efectos de los fármacos , Tracto Gastrointestinal/inmunología , Tracto Gastrointestinal/microbiología , Inmunidad/efectos de los fármacos , Inmunidad/inmunología , Interleucina-10/inmunología , Interleucina-12/inmunología , Interleucina-6/inmunología , Ratones , Ratones Endogámicos BALB C , Ratones Endogámicos C57BL , Linfocitos T/efectos de los fármacos , Linfocitos T/inmunología , Factor de Necrosis Tumoral alfa/inmunologíaRESUMEN
Human brucellosis is a protean disease with a diversity of clinical signs and symptoms resulting from infection with Brucella species. Recent reports suggest a cross-regulation between adrenal steroids (cortisol and dehydroepiandrosterone [DHEA]) and the immune system. Monocytes and macrophages are the main replication niche for Brucella. Therefore, we investigated the role of adrenal hormones on the modulation of the immune response mediated by macrophages in B. abortus infection. Cortisol treatment during B. abortus infection significantly inhibits cytokine, chemokine, and MMP-9 secretion. In contrast, DHEA treatment had no effect. However, DHEA treatment increases the expression of costimulatory molecules (CD40, CD86), the adhesion molecule CD54, and major histocompatibility complex class I (MHC-I) and MHC-II expression on the surface of B. abortus-infected monocytes. It is known that B. abortus infection inhibits MHC-I and MHC-II expression induced by gamma interferon (IFN-γ) treatment. DHEA reverses B. abortus downmodulation of the MHC-I and -II expression induced by IFN-γ. Taken together, our data indicate that DHEA immune intervention may positively affect monocyte activity during B. abortus infection.