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1.
Nat Commun ; 15(1): 2161, 2024 Mar 09.
Artigo em Inglês | MEDLINE | ID: mdl-38461302

RESUMO

Human and animal tuberculosis is caused by the Mycobacterium tuberculosis Complex (MTBC), which has evolved a genomic decay of cobalamin (vitamin B12) biosynthetic genes. Accordingly, and in sharp contrast to environmental, opportunistic and ancestor mycobacteria; we demonstrate that M. tuberculosis (Mtb), M. africanum, and animal-adapted lineages, lack endogenous production of cobalamin, yet they retain the capacity for exogenous uptake. A B12 anemic model in immunocompromised and immunocompetent mice, demonstrates improved survival, and lower bacteria in organs, in B12 anemic animals infected with Mtb relative to non-anemic controls. Conversely, no differences were observed between mice groups infected with M. canettii, an ancestor mycobacterium which retains cobalamin biosynthesis. Interrogation of the B12 transcriptome in three MTBC strains defined L-methionine synthesis by metE and metH genes as a key phenotype. Expression of metE is repressed by a cobalamin riboswitch, while MetH requires the cobalamin cofactor. Thus, deletion of metE predominantly attenuates Mtb in anemic mice; although inactivation of metH exclusively causes attenuation in non-anemic controls. Here, we show how sub-physiological levels of B12 in the host antagonizes Mtb virulence, and describe a yet unknown mechanism of host-pathogen cross-talk with implications for B12 anemic populations.


Assuntos
Mycobacterium tuberculosis , Riboswitch , Tuberculose , Animais , Humanos , Camundongos , Vitamina B 12/metabolismo , Mycobacterium tuberculosis/genética , Mycobacterium tuberculosis/metabolismo , Virulência/genética
2.
Nat Commun ; 15(1): 1878, 2024 Mar 18.
Artigo em Inglês | MEDLINE | ID: mdl-38499523

RESUMO

The metabolic functions of the liver are spatially organized in a phenomenon called zonation, linked to the differential exposure of portal and central hepatocytes to nutrient-rich blood. The mTORC1 signaling pathway controls cellular metabolism in response to nutrients and insulin fluctuations. Here we show that simultaneous genetic activation of nutrient and hormone signaling to mTORC1 in hepatocytes results in impaired establishment of postnatal metabolic and zonal identity of hepatocytes. Mutant hepatocytes fail to upregulate postnatally the expression of Frizzled receptors 1 and 8, and show reduced Wnt/ß-catenin activation. This defect, alongside diminished paracrine Wnt2 ligand expression by endothelial cells, underlies impaired postnatal maturation. Impaired zonation is recapitulated in a model of constant supply of nutrients by parenteral nutrition to piglets. Our work shows the role of hepatocyte sensing of fluctuations in nutrients and hormones for triggering a latent metabolic zonation program.


Assuntos
Células Endoteliais , Fígado , Suínos , Animais , Alvo Mecanístico do Complexo 1 de Rapamicina/genética , Alvo Mecanístico do Complexo 1 de Rapamicina/metabolismo , Células Endoteliais/metabolismo , Fígado/metabolismo , Hepatócitos/metabolismo , Transdução de Sinais , Insulina/metabolismo
3.
Nat Commun ; 14(1): 6090, 2023 10 04.
Artigo em Inglês | MEDLINE | ID: mdl-37794033

RESUMO

Intravesical administration of Bacillus Calmette-Guérin (BCG) was one of the first FDA-approved immunotherapies and remains a standard treatment for bladder cancer. Previous studies have demonstrated that intravenous (IV) administration of BCG is well-tolerated and effective in preventing tuberculosis infection in animals. Here, we examine IV BCG in several preclinical lung tumor models. Our findings demonstrate that BCG inoculation reduced tumor growth and prolonged mouse survival in models of lung melanoma metastasis and orthotopic lung adenocarcinoma. Moreover, IV BCG treatment was well-tolerated with no apparent signs of acute toxicity. Mechanistically, IV BCG induced tumor-specific CD8+ T cell responses, which were dependent on type 1 conventional dendritic cells, as well as NK cell-mediated immunity. Lastly, we also show that IV BCG has an additive effect on anti-PD-L1 checkpoint inhibitor treatment in mouse lung tumors that are otherwise resistant to anti-PD-L1 as monotherapy. Overall, our study demonstrates the potential of systemic IV BCG administration in the treatment of lung tumors, highlighting its ability to enhance immune responses and augment immune checkpoint blockade efficacy.


Assuntos
Neoplasias Pulmonares , Neoplasias da Bexiga Urinária , Camundongos , Animais , Vacina BCG , Neoplasias da Bexiga Urinária/patologia , Linfócitos T CD8-Positivos , Administração Intravenosa , Imunidade Celular , Células Matadoras Naturais , Pulmão/patologia , Neoplasias Pulmonares/tratamento farmacológico
4.
Rev. esp. podol ; 34(1): 32-34, 2023. ilus, tab
Artigo em Espanhol | IBECS | ID: ibc-226670

RESUMO

Objetivos: Los anestésicos locales de tipo amida empleados en cirugía podológica, como la lidocaína o mepivacaína, poseen cierto poder vasodilatador. Puesto que en algunas técnicas quirúrgicas puede haber sangrado postquirúrgico abundante, conocer si alguno de los dos anestésicos tiene mayor o menor efecto vasodilatador podría mejorar la respuesta postquirúrgica a estas técnicas. Así pues, el objetivo de este estudio fue comparar la respuesta térmica en el primer dedo tras la aplicación de los dos anestésicos al 2 %. Pacientes y métodos: Veintiséis participantes sanos se ofrecieron voluntarios para participar en este ensayo clínico aleatorizado con doble ciego. Los sujetos fueron divididos en dos grupos: lidocaína 2 % (n = 13) y mepivacaína 2 % (n = 13). Ambos grupos recibieron 1 cc del anestésico indicado. Se realizó una fotografía termográfica previa y tras 10 minutos al bloqueo troncular del hallux para cuantificar el aumento de temperatura. No se registraron complicaciones ni reacciones adversas. Resultados: Los dos grupos eran similares en cuanto a características antropométricas. No se observaron diferencias significativas entre grupos ni en la media de temperatura pre-anestésica (24.38 °C grupo lidocaína, 24.75 °C grupo mepivacaína, p = 0.918), ni en la media de temperatura postanestésica de los sujetos (31.3 °C para ambos grupos, p = 0.959). Los resultados de la diferencia pre-post anestésica fue de 6.91 °C para el grupo lidocaína y de 6.54 °C para el grupo mepivacaína, siendo esta diferencia estadísticamente no significativa (p = 0.7). Sin embargo, todos los sujetos (n = 26) mostraron un aumento de la temperatura tras la anestesia (p < 0.001). Conclusiones: Ambos fármacos mostraron una elevación de la temperatura en los sujetos y, por tanto, su poder vasoactivo. En cambio, no se evidenciaron diferencias significativas entre grupos...(AU)


Objectives: Local anaesthetics such as lidocaine or mepivacaine, commonly used in toenail surgery, have an associated vasodilator effect. Although is thought that lidocaine has a greater vasodilator effect than mepivacaine, there´s not strong in vivo evidence of this. So, the aim of this work was to assess the temperature increase experienced by the toes after be injected of 1 ml 2 % mepivacaine or lidocaine. Patients and methods: 26 participants were randomly divided into two groups and a pre-anæsthetic thermal image (Flir E60bx camera) was taken. Patients in group A (n = 13) received 1 ml of 2 % lidocaine, while those in group B (n = 13) received 1 ml of 2 % mepivacaine at four points of the hallux. After 10 minutes a second thermal image (post-anæsthetic image). Mean temperatures were assessed at the proximal phalanx and the pad of the hallux. Results: After application of the anæsthetic, the mean temperatures were 31.3 ± 3.07 °C at point 1 and 30.8 ± 3.08 °C at point 2 in the lidocaine group, and 31.3 ± 2.74 °C at point 1 and 29.5 ± 2.87 °C at point 2 in the mepivacaine group, with not statistically significant differences between them (p = 0.959 and p = 0.798). All the participants experienced temperature increases of between 5.13 °C and 6.91 °C, but there were no significant differences between groups (p = 0.7 and p = 0.0778). Conclusions: Even though most of the literature suggests that lidocaine has more potent vasodilator effect than mepivacaine, the present results do not reflect any real clinical impact distinguishing one drug from the other in the field block of the big toe, as measured with infrared thermal imaging.(AU)


Assuntos
Humanos , Masculino , Feminino , Adulto , Unhas Encravadas/tratamento farmacológico , Vasodilatadores/administração & dosagem , Hallux/diagnóstico por imagem , Unhas Encravadas/cirurgia , Anestésicos Locais/administração & dosagem , Unhas Encravadas , Unhas Encravadas/diagnóstico por imagem , Hallux , Mepivacaína/administração & dosagem , Podiatria
5.
Genome Biol ; 23(1): 230, 2022 10 31.
Artigo em Inglês | MEDLINE | ID: mdl-36316722

RESUMO

BACKGROUND: Overweight and obesity are defined by an anomalous or excessive fat accumulation that may compromise health. To find single-nucleotide polymorphisms (SNPs) influencing metabolic phenotypes associated with the obesity state, we analyze multiple anthropometric and clinical parameters in a cohort of 790 healthy volunteers and study potential associations with 48 manually curated SNPs, in metabolic genes functionally associated with the mechanistic target of rapamycin (mTOR) pathway. RESULTS: We identify and validate rs2291007 within a conserved region in the 3'UTR of folliculin-interacting protein FNIP2 that correlates with multiple leanness parameters. The T-to-C variant represents the major allele in Europeans and disrupts an ancestral target sequence of the miRNA miR-181b-5p, thus resulting in increased FNIP2 mRNA levels in cancer cell lines and in peripheral blood from carriers of the C allele. Because the miRNA binding site is conserved across vertebrates, we engineered the T-to-C substitution in the endogenous Fnip2 allele in mice. Primary cells derived from Fnip2 C/C mice show increased mRNA stability, and more importantly, Fnip2 C/C mice replicate the decreased adiposity and increased leanness observed in human volunteers. Finally, expression levels of FNIP2 in both human samples and mice negatively associate with leanness parameters, and moreover, are the most important contributor in a multifactorial model of body mass index prediction. CONCLUSIONS: We propose that rs2291007 influences human leanness through an evolutionarily conserved modulation of FNIP2 mRNA levels.


Assuntos
MicroRNAs , Sobrepeso , Humanos , Animais , Camundongos , Regiões 3' não Traduzidas , Sobrepeso/genética , Magreza/genética , MicroRNAs/genética , MicroRNAs/metabolismo , Polimorfismo de Nucleotídeo Único , RNA Mensageiro/genética , RNA Mensageiro/metabolismo , Obesidade/genética , Proteínas de Transporte/metabolismo
6.
Sci Adv ; 8(35): eabo1215, 2022 Sep 02.
Artigo em Inglês | MEDLINE | ID: mdl-36044577

RESUMO

Selective degradation of the endoplasmic reticulum (ER) via autophagy (ER-phagy) is initiated by ER-phagy receptors, which facilitate the incorporation of ER fragments into autophagosomes. FAM134 reticulon family proteins (FAM134A, FAM134B, and FAM134C) are ER-phagy receptors with structural similarities and nonredundant functions. Whether they respond differentially to the stimulation of ER-phagy is unknown. Here, we describe an activation mechanism unique to FAM134C during starvation. In fed conditions, FAM134C is phosphorylated by casein kinase 2 (CK2) at critical residues flanking the LIR domain. Phosphorylation of these residues negatively affects binding affinity to the autophagy proteins LC3. During starvation, mTORC1 inhibition limits FAM134C phosphorylation by CK2, hence promoting receptor activation and ER-phagy. Using a novel tool to study ER-phagy in vivo and FAM134C knockout mice, we demonstrated the physiological relevance of FAM134C phosphorylation during starvation-induced ER-phagy in liver lipid metabolism. These data provide a mechanistic insight into ER-phagy regulation and an example of autophagy selectivity during starvation.

7.
J Immunother Cancer ; 10(7)2022 07.
Artigo em Inglês | MEDLINE | ID: mdl-35781395

RESUMO

BACKGROUND: Intravesical BCG is the gold-standard therapy for non-muscle invasive bladder cancer (NMIBC); however, it still fails in a significant proportion of patients, so improved treatment options are urgently needed. METHODS: Here, we compared BCG antitumoral efficacy with another live attenuated mycobacteria, MTBVAC, in an orthotopic mouse model of bladder cancer (BC). We aimed to identify both bacterial and host immunological factors to understand the antitumoral mechanisms behind effective bacterial immunotherapy for BC. RESULTS: We found that the expression of the BCG-absent proteins ESAT6/CFP10 by MTBVAC was determinant in mediating bladder colonization by the bacteria, which correlated with augmented antitumoral efficacy. We further analyzed the mechanism of action of bacterial immunotherapy and found that it critically relied on the adaptive cytotoxic response. MTBVAC enhanced both tumor antigen-specific CD4+ and CD8+ T-cell responses, in a process dependent on stimulation of type 1 conventional dendritic cells. Importantly, improved intravesical bacterial immunotherapy using MBTVAC induced eradication of fully established bladder tumors, both as a monotherapy and specially in combination with the immune checkpoint inhibitor antiprogrammed cell death ligand 1 (anti PD-L1). CONCLUSION: These results contribute to the understanding of the mechanisms behind successful bacterial immunotherapy against BC and characterize a novel therapeutic approach for BCG-unresponsive NMIBC cases.


Assuntos
Neoplasias da Bexiga Urinária , Animais , Vacina BCG/uso terapêutico , Bactérias , Inibidores de Checkpoint Imunológico , Imunoterapia , Camundongos , Neoplasias da Bexiga Urinária/terapia
8.
Biosensors (Basel) ; 11(12)2021 Dec 20.
Artigo em Inglês | MEDLINE | ID: mdl-34940281

RESUMO

Enzyme-linked immunosorbent assay (ELISA) is routinely used to detect biomolecules related to several diseases facilitating diagnosis and monitoring of these, as well as the possibility of decreasing their mortality rate. Several methods have been carried out to improve the ELISA sensitivity through antibodies immobilization on the microtiter plates. Here, we have developed a strategy of antibodies immobilization to improve the ELISA sensitivity increasing the antibody density surface through the tetrazine (Tz)-trans-cyclooctene (TCO) reaction. For this, we prepared surfaces with tetrazine groups while the captured antibody was conjugated with TCO. The tetrazine surfaces were prepared in two different ways: (1) from aminated plates and (2) from Tz-BSA-coated plates. The surfaces were evaluated using two sandwich ELISA models, one of them using the low-affinity antibody anti-c-myc as a capture antibody to detect the c-myc-GST-IL8h recombinant protein, and the other one to detect the carcinoembryonic human protein (CEA). The sensitivity increased in both surfaces treated with tetrazine in comparison with the standard unmodified surface. The c-myc-GST-IL8h detection was around 10-fold more sensible on both tetrazine surfaces, while CEA ELISA detection increased 12-fold on surfaces coated with Tz-BSA. In conclusion, we show that it is possible to improve the ELISA sensitivity using this immobilization system, where capture antibodies bond covalently to surfaces.


Assuntos
Anticorpos , Antígeno Carcinoembrionário , Anticorpos/imunologia , Antígeno Carcinoembrionário/imunologia , Ensaio de Imunoadsorção Enzimática , Humanos
9.
STAR Protoc ; 2(4): 100918, 2021 12 17.
Artigo em Inglês | MEDLINE | ID: mdl-34755120

RESUMO

We present a protocol for measuring the activity of the mechanistic target of rapamycin (mTOR) pathway in ex vivo isolated mouse primary hepatocytes. It can be used as a tool for genetic, pharmacological, metabolomic, and signal transduction procedures. We discuss critical aspects for improving yield, viability, and modulation of the mTOR pathway. This protocol can be adapted to other signaling cascades and is compatible with multiple readouts. For complete details on the use and execution of this protocol, please refer to Ortega-Molina et al. (2021).


Assuntos
Técnicas de Cultura de Células/métodos , Hepatócitos/metabolismo , Fígado/citologia , Serina-Treonina Quinases TOR , Animais , Células Cultivadas , Camundongos , Transdução de Sinais/fisiologia , Serina-Treonina Quinases TOR/análise , Serina-Treonina Quinases TOR/metabolismo
10.
Sci Immunol ; 6(63): eabc2934, 2021 Sep 24.
Artigo em Inglês | MEDLINE | ID: mdl-34559551

RESUMO

Bacillus Calmette-Guerin (BCG) is an attenuated bacterial vaccine used to protect against Mycobacterium tuberculosis (Mtb) in regions where infections are highly prevalent. BCG is currently delivered by the intradermal route, but alternative routes of administration are of great interest, including intrapulmonary delivery to more closely mimic respiratory Mtb infection. In this study, mice subjected to pulmonary delivery of green fluorescent protein­tagged strains of virulent (Mtb) and attenuated (BCG) mycobacteria were studied to better characterize infected lung cell subsets. Profound differences in dissemination patterns were detected between Mtb and BCG, with a strong tendency of Mtb to disseminate from alveolar macrophages (AMs) to other myeloid subsets, mainly neutrophils and recruited macrophages. BCG mostly remained in AMs, which promoted their activation. These preactivated macrophages were highly efficient in containing Mtb bacilli upon challenge and disrupting early bacterial dissemination, which suggests a potential mechanism of protection associated with pulmonary BCG vaccination. Respiratory BCG also protected mice against a lethal Streptococcus pneumoniae challenge, suggesting that BCG-induced innate activation could confer heterologous protection against respiratory pathogens different from Mtb. BCG drove long-term activation of AMs, even after vaccine clearance, and these AMs reacted efficiently upon subsequent challenge. These results suggest the generation of a trained innate memory-like response in AMs induced by pulmonary BCG vaccination.


Assuntos
Vacina BCG/imunologia , Tuberculose Pulmonar/imunologia , Animais , Modelos Animais de Doenças , Pulmão/imunologia , Ativação de Macrófagos , Camundongos , Camundongos Endogâmicos C57BL , Camundongos Transgênicos , Mycobacterium tuberculosis/imunologia
11.
Cell Rep ; 36(2): 109372, 2021 07 13.
Artigo em Inglês | MEDLINE | ID: mdl-34260908

RESUMO

B lymphocytes are exquisitely sensitive to fluctuations in nutrient signaling by the Rag GTPases, and 15% of follicular lymphomas (FLs) harbor activating mutations in RRAGC. Hence, a potential therapeutic approach against malignant B cells is to inhibit Rag GTPase signaling, but because such inhibitors are still to be developed, efficacy and safety remain unknown. We generated knockin mice expressing a hypomorphic variant of RagC (Q119L); RagCQ119L/+ mice are viable and show attenuated nutrient signaling. B lymphocyte activation is cell-intrinsically impaired in RagCQ119L/+ mice, which also show significant suppression of genetically induced lymphomagenesis and autoimmunity. Surprisingly, no overt systemic trade-offs or phenotypic alterations caused by partial suppression of nutrient signaling are seen in other organs, and RagCQ119L/+ mice show normal longevity and normal age-dependent health decline. These results support the efficacy and safety of moderate inhibition of nutrient signaling against pathological B cells.


Assuntos
Linfócitos B/imunologia , Carcinogênese/imunologia , Carcinogênese/patologia , Linfoma/imunologia , Linfoma/patologia , Proteínas Monoméricas de Ligação ao GTP/metabolismo , Transdução de Sinais , Animais , Feminino , Técnicas de Introdução de Genes , Heterozigoto , Imunidade Humoral , Longevidade , Masculino , Alvo Mecanístico do Complexo 1 de Rapamicina/metabolismo , Camundongos Mutantes , Mutação/genética
12.
Nat Commun ; 12(1): 3660, 2021 06 16.
Artigo em Inglês | MEDLINE | ID: mdl-34135321

RESUMO

The mechanistic target of rapamycin complex 1 (mTORC1) integrates cellular nutrient signaling and hormonal cues to control metabolism. We have previously shown that constitutive nutrient signaling to mTORC1 by means of genetic activation of RagA (expression of GTP-locked RagA, or RagAGTP) in mice resulted in a fatal energetic crisis at birth. Herein, we rescue neonatal lethality in RagAGTP mice and find morphometric and metabolic alterations that span glucose, lipid, ketone, bile acid and amino acid homeostasis in adults, and a median lifespan of nine months. Proteomic and metabolomic analyses of livers from RagAGTP mice reveal a failed metabolic adaptation to fasting due to a global impairment in PPARα transcriptional program. These metabolic defects are partially recapitulated by restricting activation of RagA to hepatocytes, and revert by pharmacological inhibition of mTORC1. Constitutive hepatic nutrient signaling does not cause hepatocellular damage and carcinomas, unlike genetic activation of growth factor signaling upstream of mTORC1. In summary, RagA signaling dictates dynamic responses to feeding-fasting cycles to tune metabolism so as to match the nutritional state.


Assuntos
Jejum/metabolismo , Fígado/metabolismo , Proteínas Monoméricas de Ligação ao GTP/metabolismo , Transdução de Sinais , Animais , Modelos Animais de Doenças , Glucose/metabolismo , Homeostase , Humanos , Alvo Mecanístico do Complexo 1 de Rapamicina/antagonistas & inibidores , Alvo Mecanístico do Complexo 1 de Rapamicina/metabolismo , Camundongos , Proteínas Monoméricas de Ligação ao GTP/genética , Nutrientes/metabolismo , PPAR alfa/genética , PPAR alfa/metabolismo , Fenótipo , Proteômica , Transdução de Sinais/efeitos dos fármacos , Sirolimo/administração & dosagem , Sirolimo/farmacologia , Transcrição Gênica/efeitos dos fármacos , Proteína 1 do Complexo Esclerose Tuberosa/genética , Proteína 1 do Complexo Esclerose Tuberosa/metabolismo
13.
Int J Nurs Stud ; 120: 103975, 2021 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-34102371

RESUMO

BACKGROUND: The ageing of the population is leading to an increase in the number of elderly patients with acute myocardial infarction. These patients are at higher risk for complications and poor medication adherence, which in turn are associated with higher healthcare resource expenditures. Nursing programmes might help to improve adherence in these complex patients. OBJECTIVE: The objective of this study was to assess the impact of a nursing intervention on therapeutic adherence in elderly patients after myocardial infarction compared to a control group. DESIGN: A single-blind, randomized controlled trial. SETTINGS: Heart disease institute of a tertiary care hospital. PARTICIPANTS: Patients aged ≥75 years with myocardial infarction undergoing percutaneous coronary intervention. METHODS: A comprehensive geriatric assessment was performed during the admission in all patients (N=143). Patients were randomly allocated to a nursing intervention group (n=68) or a usual care group (n=75). In patients from the intervention group, a nursing intervention programme was performed 3 months after admission based on education support and patient monitoring to improve therapeutic adherence. The main outcome measured was 12-months therapeutic adherence, as defined by a combination of measurement tools (Morisky-Green and Hayness-Sacket scales, attendance at visits and withdrawal of medication from the pharmacy). Therapeutic adherence was assessed by nurses blinded to the assignment group. RESULTS: The mean age was 82.2 years. The proportion of comorbidities was significant (diabetes mellitus 51/143 (35.7%), hypertension 110/143 (76.9%), prior stroke 22/143 (15.4%)). Likewise, the proportion of geriatric syndromes was noticeable (frailty 26/143 (18.2%), risk of malnutrition 38/143 (26.6%), cognitive impairment 28/143 (19.6%)). Most patients (92.3%) had a low educational level. A total of 119 patients achieved 12-month assessment adherence. Among these patients, the proportions of adherence were as follows: Morisky-Green test: 76/119 (63.9%), Haynes-Sackett test 99/119 (83.2%), medical visits compliance 95/119 (79.8%), and correct acquisition of drugs in the pharmacy 74/119 (62.2%). A total of 42/119 patients (35.3%) were adherent as defined by the combination of the 4 measures. Therapeutic adherence at 12 months was achieved in a significantly higher proportion of patients from the nursing intervention group (51.9% vs 21.5%, p<0.001). CONCLUSION: A significant proportion of elderly patients with myocardial infarction were non-adherent at 12 months. The proportion of adherent patients was highly variable according to the different tools used. A structured nursing intervention was independently associated with a higher adherence rate, as assessed by a multidimensional measurement, in this subset of complex high-risk elderly patients with myocardial infarction. TRIAL REGISTRATION: Registered with www.clinicaltrials.gov (NCT04662762).


Assuntos
Infarto do Miocárdio , Enfermeiras e Enfermeiros , Intervenção Coronária Percutânea , Idoso , Idoso de 80 Anos ou mais , Humanos , Adesão à Medicação , Infarto do Miocárdio/tratamento farmacológico , Método Simples-Cego
14.
EBioMedicine ; 64: 103186, 2021 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-33478923

RESUMO

BACKGROUND: Substantial recent advances in the comprehension of the molecular and cellular mechanisms behind asthma have evidenced the importance of the lung immune environment for disease outcome, making modulation of local immune responses an attractive therapeutic target against this pathology. Live attenuated mycobacteria, such as the tuberculosis vaccine BCG, have been classically linked with a type 1 response, and proposed as possible modulators of the type 2 response usually associated with asthma. METHODS: In this study we used different acute and chronic murine models of asthma to investigate the therapeutic efficacy of intranasal delivery of the live tuberculosis vaccines BCG and MTBVAC by regulating the lung immune environment associated with airway hyperresponsiveness (AHR). FINDINGS: Intranasal administration of BCG, or the novel tuberculosis vaccine candidate MTBVAC, abrogated AHR-associated hallmarks, including eosinophilia and lung remodeling. This correlated with the re-polarization of allergen-induced M2 macrophages towards an M1 phenotype, as well as with the induction of a strong allergen-specific Th1 response. Importantly, vaccine treatment was effective in a scenario of established chronic asthma where a strong eosinophil infiltration was already present prior to immunization. We finally compared the nebulization efficiency of clinical formulations of MTBVAC and BCG using a standard commercial nebulizer for potential aerosol application. INTERPRETATION: Our results demonstrate that pulmonary live tuberculosis vaccines efficiently revert established asthma in mice. These data support the further exploration of this approach as potential therapy against asthma. FUNDING: Spanish Ministry of Science [grant numbers: BIO2014-5258P, RTI2018-097625-B-I00], Instituto de Salud Carlos III, Gobierno de Aragón/Fondo Social Europeo, University of Zaragoza [grant number: JIUZ-2018-BIO-01].


Assuntos
Asma/imunologia , Asma/terapia , Vacinas contra a Tuberculose/uso terapêutico , Vacinas Atenuadas/uso terapêutico , Administração Intranasal , Remodelação das Vias Aéreas/imunologia , Alérgenos/imunologia , Animais , Vacina BCG , Biomarcadores , Microambiente Celular/imunologia , Citocinas/metabolismo , Modelos Animais de Doenças , Eosinófilos/imunologia , Eosinófilos/metabolismo , Eosinófilos/patologia , Feminino , Imunização , Camundongos , Ovalbumina/imunologia , Vacinas contra a Tuberculose/administração & dosagem , Vacinas Atenuadas/administração & dosagem
15.
PLoS Pathog ; 16(12): e1009061, 2020 12.
Artigo em Inglês | MEDLINE | ID: mdl-33347499

RESUMO

Species belonging to the Mycobacterium tuberculosis Complex (MTBC) show more than 99% genetic identity but exhibit distinct host preference and virulence. The molecular genetic changes that underly host specificity and infection phenotype within MTBC members have not been fully elucidated. Here, we analysed RD900 genomic region across MTBC members using whole genome sequences from 60 different MTBC strains so as to determine its role in the context of MTBC evolutionary history. The RD900 region comprises two homologous genes, pknH1 and pknH2, encoding a serine/threonine protein kinase PknH flanking the tbd2 gene. Our analysis revealed that RD900 has been independently lost in different MTBC lineages and different strains, resulting in the generation of a single pknH gene. Importantly, all the analysed M. bovis and M. caprae strains carry a conserved deletion within a proline rich-region of pknH, independent of the presence or absence of RD900. We hypothesized that deletion of pknH proline rich-region in M. bovis may affect PknH function, having a potential role in its virulence and evolutionary adaptation. To explore this hypothesis, we constructed two M. bovis 'knock-in' strains containing the M. tuberculosis pknH gene. Evaluation of their virulence phenotype in mice revealed a reduced virulence of both M. bovis knock-in strains compared to the wild type, suggesting that PknH plays an important role in the differential virulence phenotype of M. bovis vs M. tuberculosis.


Assuntos
Proteínas de Bactérias/genética , Interações entre Hospedeiro e Microrganismos/genética , Mycobacterium tuberculosis/genética , Proteínas Serina-Treonina Quinases/genética , Animais , Proteínas de Bactérias/metabolismo , Feminino , Genômica , Masculino , Camundongos , Camundongos Endogâmicos C57BL , Mycobacterium tuberculosis/patogenicidade , Polimorfismo Genético/genética , Proteínas Serina-Treonina Quinases/metabolismo , Virulência/genética
16.
Front Microbiol ; 11: 1339, 2020.
Artigo em Inglês | MEDLINE | ID: mdl-32625195

RESUMO

Vaccination through the natural route of infection represents an attractive immunization strategy in vaccinology. In the case of tuberculosis, vaccine delivery by the respiratory route has regained interest in recent years, showing efficacy in different animal models. In this context, respiratory vaccination triggers lung immunological mechanisms which are omitted when vaccines are administered by parenteral route. However, contribution of mucosal antibodies to vaccine- induced protection has been poorly studied. In the present study, we evaluated in mice and non-human primates (NHP) a novel whole cell inactivated vaccine (MTBVAC HK), by mucosal administration. MTBVAC HK given by intranasal route to BCG-primed mice substantially improved the protective efficacy conferred by subcutaneous BCG only. Interestingly, this improved protection was absent in mice lacking polymeric Ig receptor (pIgR), suggesting a crucial role of mucosal secretory immunoglobulins in protective immunity. Our study in NHP confirmed the ability of MTBVAC HK to trigger mucosal immunoglobulins. Importantly, in vitro assays demonstrated the functionality of these immunoglobulins to induce M. tuberculosis opsonization in the presence of human macrophages. Altogether, our results suggest that mucosal immunoglobulins can be induced by vaccination to improve protection against tuberculosis and therefore, they represent a promising target for next generation tuberculosis vaccines.

17.
Cells ; 7(11)2018 Nov 02.
Artigo em Inglês | MEDLINE | ID: mdl-30400258

RESUMO

BACKGROUND: Advanced cirrhosis is related to alterations in immunity. We aimed to evaluate the levels of peripheral CD4⁺ T cells (Tregs) and plasma cytokine in patients coinfected with human immunodeficiency virus and hepatitis C virus (HIV/HCV) according to liver fibrosis stages [evaluated as liver stiffness measure (LSM)] and their linear relationship. METHODS: We performed a cross-sectional study on 238 HIV/HCV-coinfected patients (119 had <12.5 kPa, 73 had 12.5⁻25 kPa, and 46 had >25 kPa). Peripheral T-cell subsets were phenotyped by flow cytometry, plasma biomarkers were assessed by multiplex immunoassays, and LSM was assessed by transient elastography. Results: We found HIV/HCV-coinfected patients had higher values of CD4⁺ Tregs (p < 0.001), memory Tregs (p ≤ 0.001), and plasma cytokine levels [IFN-γ (p ≤ 0.05) and IL-10 (p ≤ 0.01)] compared with healthy donors and HIV-monoinfected patients. In the multivariate analysis, higher LSM values were associated with reduced levels of IL-10 (adjusted arithmetic mean ratio (aAMR) = 0.83; p = 0.019), IL-2 (aAMR = 0.78; p = 0.017), TNF-α (aAMR = 0.67; p < 0.001), and IL-17A (aAMR = 0.75; p = 0.006). When we focus on HIV/HCV-coinfected patients analyzed by LSM strata, patients with ≥25 kPa had lower values of IL-2 (aAMR = 0.66; p = 0.021), TNF-α (aAMR = 0.565; p = 0.003), and IL-17A (aAMR = 0.58; p = 0.003) than patients with <12.5 kPa. CONCLUSION: HIV/HCV-coinfected patients showed an immunosuppressive profile compared to healthy controls and HIV-monoinfected patients. Additionally, HIV/HCV-coinfected patients with advanced cirrhosis (LSM ≥ 25 kPa) had the lowest plasma values of cytokines related to Th1 (IL-2 and TNF-α) and Th17 (IL-17A) response.

18.
Transl Res ; 197: 32-42, 2018 07.
Artigo em Inglês | MEDLINE | ID: mdl-29702078

RESUMO

Intravesical instillation of bacillus Calmette-Guérin (BCG) has been a first-line therapy for non-muscle-invasive bladder cancer for the last 4 decades. However, this treatment causes serious adverse events in a significant number of patients and a substantial percentage of recurrence episodes. MTBVAC is a live-attenuated vaccine derived from a Mycobacterium tuberculosis clinical isolate and is currently under evaluation in clinical trials to replace BCG as a tuberculosis vaccine. Here, we describe for the first time the potential of MTBVAC as a bladder cancer therapy in vitro and in vivo in a preclinical model. MTBVAC colonized human bladder tumor cells to a much greater extent than BCG via a mechanism mediated by macropinocytosis and induced cell growth inhibition after internalization. In vivo testing in an orthotopic murine model of bladder cancer demonstrated a higher antitumor effect of MTBVAC in experimental conditions in which BCG did not work. Our data encourage further studies to support the possible application of MTBVAC as a new immunotherapeutic agent for bladder cancer.


Assuntos
Mycobacterium tuberculosis/imunologia , Vacinas contra a Tuberculose/uso terapêutico , Neoplasias da Bexiga Urinária/tratamento farmacológico , Vacinas Atenuadas/uso terapêutico , Administração Intravesical , Animais , Antineoplásicos , Vacina BCG/imunologia , Linhagem Celular , Linhagem Celular Tumoral , Proliferação de Células , Modelos Animais de Doenças , Humanos , Camundongos , Pinocitose , Resultado do Tratamento , Neoplasias da Bexiga Urinária/patologia
19.
Nat Commun ; 8: 16085, 2017 07 14.
Artigo em Inglês | MEDLINE | ID: mdl-28706226

RESUMO

MTBVAC is a live-attenuated Mycobacterium tuberculosis vaccine, currently under clinical development, that contains the major antigens ESAT6 and CFP10. These antigens are absent from the current tuberculosis vaccine, BCG. Here we compare the protection induced by BCG and MTBVAC in several mouse strains that naturally express different MHC haplotypes differentially recognizing ESAT6 and CFP10. MTBVAC induces improved protection in C3H mice, the only of the three tested strains reactive to both ESAT6 and CFP10. Deletion of both antigens in MTBVAC reduces its efficacy to BCG levels, supporting a link between greater efficacy and CFP10- and ESAT6-specific reactogenicity. In addition, MTBVAC (but not BCG) triggers a specific response in human vaccinees against ESAT6 and CFP10. Our results warrant further exploration of this response as potential biomarker of protection in MTBVAC clinical trials.


Assuntos
Antígenos de Bactérias/imunologia , Proteínas de Bactérias/imunologia , Vacinas contra a Tuberculose/imunologia , Animais , Antígenos de Bactérias/genética , Proteínas de Bactérias/genética , Feminino , Expressão Gênica , Interações Hospedeiro-Patógeno/genética , Camundongos Endogâmicos , Mycobacterium tuberculosis
20.
Vaccine ; 32(40): 5192-7, 2014 Sep 08.
Artigo em Inglês | MEDLINE | ID: mdl-25066740

RESUMO

Safety of individuals at risk of immune suppression is an important concern for live vaccines. The new-generation tuberculosis vaccine candidate MTBVAC, a genetically engineered doubly attenuated Mycobacterium tuberculosis mutant with deletions in phoP and fadD26 virulence genes has demonstrated comparable safety in different relevant animal models and superior protection in mice as compared to the only currently licensed tuberculosis vaccine Mycobacterium bovis BCG. Here we describe the construction of a highly attenuated MTBVAC-based live vaccine by an additional gene inactivation generated in erp of MTBVAC. The gene product of erp is an exported repeated protein (Erp), a virulence factor described to be involved in intracellular replication of M. tuberculosis. The resultant strain, MTBVAC erp(-), was tested in severe combined immunodeficiency (SCID) mouse model showing to be severely attenuated when compared to BCG and MTBVAC. Experiments conducted in immunocompetent mice revealed that the hyper-attenuated profile observed with MTBVAC erp(-) strain did not compromise its protective efficacy profile in comparison with BCG. These results postulate MTBVAC erp(-) as a potential tuberculosis vaccine candidate for use in high-risk populations of immune suppression (e.g., due to HIV infection), where the use of BCG is not recommended.


Assuntos
Proteínas de Bactérias/genética , Proteínas de Membrana/genética , Mycobacterium tuberculosis/genética , Vacinas contra a Tuberculose/imunologia , Tuberculose/prevenção & controle , Animais , Vacina BCG/imunologia , Linhagem Celular , Modelos Animais de Doenças , Camundongos Endogâmicos C57BL , Camundongos SCID , Vacinas Atenuadas/imunologia
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