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1.
Tuberculosis (Edinb) ; 143: 102418, 2023 12.
Artículo en Inglés | MEDLINE | ID: mdl-37813014

RESUMEN

Pulmonary tuberculosis (TB) inflammation is an underestimated disease complication which anti-inflammatory drugs may alleviate. This study explored the potential use of the COX-2 inhibitors acetylsalicylic acid (ASA) and celecoxib in 12 TB patients and 12 healthy controls using a whole-blood ex vivo model where TNFα, PGE2, and LTB4 plasma levels were quantitated by ELISA; we also measured COX-2, 5-LOX, 12-LOX, and 15-LOX gene expression. We observed a significant TNFα production in response to stimulation with LPS or M. tuberculosis (Mtb). Celecoxib, but not ASA, reduced TNFα and PGE2 production, while increasing LTB4 in patients after infection with Mtb. Gene expression of COX-2 and 5-LOX was higher in controls, while 12-LOX was significantly higher in patients. 15-LOX expression was similar in both groups. We concluded that COX-2 inhibitors downregulate inflammation after Mtb infection, and our methodology offers a straightforward time-efficient approach for evaluating different drugs in this context. Further research is warranted to elucidate the underlying mechanisms and assess the potential clinical benefit.


Asunto(s)
Mycobacterium tuberculosis , Tuberculosis , Humanos , Celecoxib/farmacología , Celecoxib/uso terapéutico , Ciclooxigenasa 2/metabolismo , Inhibidores de la Ciclooxigenasa 2/farmacología , Inhibidores de la Ciclooxigenasa 2/uso terapéutico , Dinoprostona , Inmunidad , Inflamación/metabolismo , Leucotrieno B4/metabolismo , Mycobacterium tuberculosis/metabolismo , Tuberculosis/tratamiento farmacológico , Factor de Necrosis Tumoral alfa
2.
Front Immunol ; 14: 1241121, 2023.
Artículo en Inglés | MEDLINE | ID: mdl-37753080

RESUMEN

Introduction: Pulmonary dysfunction is an underestimated complication in tuberculosis (TB) infection, affecting quality of life (QoL). Although respiratory function tests objectively reflect lung disturbances in a specific moment, predictors of illness severity at the time of diagnosis are still lacking. Methods: We measured serum pro-inflammatory cytokines (TNF-α and IL-8), eicosanoids (PGE2, LTB4, RvD1, Mar1, and LXA4), a marker of tissue damage (cell-free nucleosomes), and indicators of redox status (malonaldehyde, 8-isoprostane, total oxidants, and antioxidants), as well as a score of radiological abnormalities (SRA) and a QoL questionnaire, in 25 patients with pulmonary TB at the time of diagnosis (t0) and two months after the initiation of treatment (t2). Results: We found higher antioxidant levels in the patients with the worst QoL at t0, and all the indicators of the prooxidant state were significantly reduced at t2, while the total antioxidant levels increased. LTB4, a pro-inflammatory eicosanoid, was diminished at t2, while all the pro-resolutory lipids decreased substantially. Significant correlations between the SRA and the QoL scores were observed, the latter showing a substantial reduction at t2, ranking it as a reliable tool for monitoring disease evolution during TB treatment. Discussion: These results suggest that evaluating a combination of these markers might be a valuable predictor of QoL improvement and a treatment response indicator; in particular, the oxidation metabolites and eicosanoid ratios could also be proposed as a future target for adjuvant therapies to reduce inflammation-associated lung injury in TB disease.


Asunto(s)
Tuberculosis Latente , Tuberculosis Pulmonar , Humanos , Calidad de Vida , Antioxidantes , Leucotrieno B4 , Tuberculosis Pulmonar/tratamiento farmacológico , Cognición
3.
J Hum Genet ; 68(10): 657-669, 2023 Oct.
Artículo en Inglés | MEDLINE | ID: mdl-37217689

RESUMEN

Hearing loss (HL) is a common heterogeneous trait that involves variants in more than 200 genes. In this study, we utilized exome (ES) and genome sequencing (GS) to effectively identify the genetic cause of presumably non-syndromic HL in 322 families from South and West Asia and Latin America. Biallelic GJB2 variants were identified in 58 probands at the time of enrollment these probands were excluded. In addition, upon review of phenotypic findings, 38/322 probands were excluded based on syndromic findings at the time of ascertainment and no further evaluation was performed on those samples. We performed ES as a primary diagnostic tool on one or two affected individuals from 212/226 families. Via ES we detected a total of 78 variants in 30 genes and showed their co-segregation with HL in 71 affected families. Most of the variants were frameshift or missense and affected individuals were either homozygous or compound heterozygous in their respective families. We employed GS as a primary test on a subset of 14 families and a secondary tool on 22 families which were unsolved by ES. Although the cumulative detection rate of causal variants by ES and GS is 40% (89/226), GS alone has led to a molecular diagnosis in 7 of 14 families as the primary tool and 5 of 22 families as the secondary test. GS successfully identified variants present in deep intronic or complex regions not detectable by ES.


Asunto(s)
Sordera , Pérdida Auditiva , Humanos , Sordera/genética , Pérdida Auditiva/genética , Pérdida Auditiva/diagnóstico , Fenotipo , Homocigoto , Mutación , Linaje
4.
NPJ Vaccines ; 8(1): 67, 2023 May 10.
Artículo en Inglés | MEDLINE | ID: mdl-37164959

RESUMEN

There is still a need for safe, efficient, and low-cost coronavirus disease 2019 (COVID-19) vaccines that can stop transmission of severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2). Here we evaluated a vaccine candidate based on a live recombinant Newcastle disease virus (NDV) that expresses a stable version of the spike protein in infected cells as well as on the surface of the viral particle (AVX/COVID-12-HEXAPRO, also known as NDV-HXP-S). This vaccine candidate can be grown in embryonated eggs at a low cost, similar to influenza virus vaccines, and it can also be administered intranasally, potentially to induce mucosal immunity. We evaluated this vaccine candidate in prime-boost regimens via intramuscular, intranasal, or intranasal followed by intramuscular routes in an open-label non-randomized non-placebo-controlled phase I clinical trial in Mexico in 91 volunteers. The primary objective of the trial was to assess vaccine safety, and the secondary objective was to determine the immunogenicity of the different vaccine regimens. In the interim analysis reported here, the vaccine was found to be safe, and the higher doses tested were found to be immunogenic when given intramuscularly or intranasally followed by intramuscular administration, providing the basis for further clinical development of the vaccine candidate. The study is registered under ClinicalTrials.gov identifier NCT04871737.

5.
Pathogens ; 11(5)2022 Apr 21.
Artículo en Inglés | MEDLINE | ID: mdl-35631013

RESUMEN

Macrophages are necessary to eliminate pathogens. However, some pathogens have developed mechanisms to avoid the immune response. One of them is modulating the cell death mechanism to favor pathogen survival. In this study, we evaluated if virulent Mycobacterium tuberculosis (M. tb) can simultaneously activate more than one cell death mechanism. We infected human monocyte-derived macrophages (MDM) in vitro with avirulent (H37Ra) and virulent (H37Rv) strains, and then we measured molecules involved in apoptosis, necroptosis, and pyroptosis. Our data showed that H37Rv infection increased the BCL-2 transcript and protein, decreased the BAX transcript, and increased phosphorylated BCL-2 at the protein level. Moreover, H37Rv infection increased the expression of the molecules involved in the necroptotic pathway, such as ASK1, p-38, RIPK1, RIPK3, and caspase-8, while H37Ra increased caspase-8 and decreased RIPK3 at the transcriptional level. In addition, NLRP3 and CASP1 expression was increased at low MOI in both strains, while IL-1ß was independent of virulence but dependent on infection MOI, suggesting the activation of pyroptosis. These findings suggest that virulent M. tb inhibits the apoptosis mediated by BCL-2 family molecules but, at the same time, increases the expression of molecules involved in apoptosis, necroptosis, and pyroptosis at the transcriptional and protein levels, probably as a mechanism to avoid the immune response and guarantee its survival.

6.
Biomolecules ; 12(4)2022 03 24.
Artículo en Inglés | MEDLINE | ID: mdl-35454079

RESUMEN

There is a sex bias in tuberculosis's severity, prevalence, and pathogenesis, and the rates are higher in men. Immunological and physiological factors are fundamental contributors to the development of the disease, and sex-related factors could play an essential role in making women more resistant to severe forms of the disease. In this study, we evaluated sex-dependent differences in inflammatory markers. Serum samples were collected from 34 patients diagnosed with pulmonary TB (19 male and 15 female) and 27 healthy controls (18 male and 9 female). Cytokines IL2, IL4, IL6, IL8, IL10, IFNγ, TNFα, and GM-CSF, and eicosanoids PGE2, LTB4, RvD1, and Mar1 were measured using commercially available immunoassays. The MDA, a product of lipidic peroxidation, was measured by detecting thiobarbituric-acid-reactive substances (TBARS). Differential inflammation patterns between men and women were observed. Men had higher levels of IL6, IL8, and TNFα than women. PGE2 and LTB4 levels were higher in patients than healthy controls, but there were no differences for RvD1 and Mar1. Women had higher RvD1/PGE2 and RvD1/LTB4 ratios among patients. RvD1 plays a vital role in resolving the inflammatory process of TB in women. Men are the major contributors to the typical pro-inflammatory profile observed in the serum of tuberculosis patients.


Asunto(s)
Tuberculosis Pulmonar , Tuberculosis , Dinoprostona , Eicosanoides , Femenino , Humanos , Inflamación/complicaciones , Interleucina-6 , Interleucina-8 , Leucotrieno B4 , Masculino , Tuberculosis/complicaciones , Tuberculosis Pulmonar/complicaciones , Factor de Necrosis Tumoral alfa
7.
medRxiv ; 2022 Feb 09.
Artículo en Inglés | MEDLINE | ID: mdl-35169806

RESUMEN

There is still a need for safe, efficient and low-cost coronavirus disease 2019 (COVID-19) vaccines that can stop transmission of severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2). Here we evaluated a vaccine candidate based on a live recombinant Newcastle disease virus (NDV) that expresses a stable version of the spike protein in infected cells as well as on the surface of the viral particle (AVX/COVID-12-HEXAPRO, also known as NDV-HXP-S). This vaccine candidate can be grown in embryonated eggs at low cost similar to influenza virus vaccines and it can also be administered intranasally, potentially to induce mucosal immunity. We evaluated this vaccine candidate in prime-boost regimens via intramuscular, intranasal, or intranasal followed by intramuscular routes in an open label non-randomized non-placebo-controlled phase I clinical trial in Mexico in 91 volunteers. The primary objective of the trial was to assess vaccine safety and the secondary objective was to determine the immunogenicity of the different vaccine regimens. In the interim analysis reported here, the vaccine was found to be safe and the higher doses tested were found to be immunogenic when given intramuscularly or intranasally followed by intramuscular administration, providing the basis for further clinical development of the vaccine candidate. The study is registered under ClinicalTrials.gov identifier NCT04871737. Funding was provided by Avimex and CONACYT.

8.
Front Immunol ; 12: 760468, 2021.
Artículo en Inglés | MEDLINE | ID: mdl-34804048

RESUMEN

Background: In the absence of a late marker of treatment failure or relapse in MDR-TB patients, biomarkers based on host-miRNAs coupled with M. tuberculosis-RNAs evaluated in extracellular vesicles (EVs) are an alternative follow-up for MDR-TB disease. Characterization of EVs cargo to identify differentially expressed miRNAs before and after treatment, and to identify M. tuberculosis-derived RNA in serum EVs from resistant TB patients. Methods: EVs were isolated from serum of 26 drug-resistant TB (DR-TB) patients and 16 healthy subjects. Differential expression of miRNAs in pooled exosomes from both untreated and treated patients was assessed and individually validated at different time points during treatment. In addition, M. tuberculosis RNA was amplified in the same samples by qPCR. Results: A multivariate analysis using miR-let-7e-5p, -197-3p and -223-3p were found to be a more sensitive discriminator between healthy individuals and those with TB for both DR-TB (AUC= 0.96, 95%, CI=0.907-1) and MDR-TB groups (AUC= 0.95, 95%, CI= 0.89-1). Upregulation of miR-let-7e-5p were observed at the time of M. tuberculosis negative culture T(3-5) for MDR-TB group or for long-term T(9-15) for MDR-TB group without diabetes (T2DM). A second pathogen-based marker based on 30kDa and 5KST sequences was detected in 33% of the MDR-TB patients after the intensive phase of treatment. The miR-let7e-5p is a candidate biomarker for long-term monitoring of treatment for the group of MDR-TB without T2DM. A dual marker of host-derived miR-let7e-5p and M. tuberculosis-derived RNA for monitoring-TB treatment based in serum EVs. Conclusion: A dual marker consisting of host-derived miR-let7e-5p and M. tuberculosis-derived RNA, could be an indicator of treatment failure or relapse time after treatment was completed.


Asunto(s)
MicroARNs , Mycobacterium tuberculosis/genética , ARN Bacteriano/sangre , Tuberculosis Resistente a Múltiples Medicamentos/tratamiento farmacológico , Adulto , Anciano , Biomarcadores/sangre , Exosomas/genética , Exosomas/metabolismo , Femenino , Humanos , Masculino , Persona de Mediana Edad , Tuberculosis Resistente a Múltiples Medicamentos/sangre , Tuberculosis Resistente a Múltiples Medicamentos/genética , Adulto Joven
9.
Antioxidants (Basel) ; 10(10)2021 Oct 05.
Artículo en Inglés | MEDLINE | ID: mdl-34679707

RESUMEN

Tuberculosis (TB) is one of the highest infectious burdens worldwide. An excess of inflammation and inadequate antioxidant defense mechanisms are believed to lead to chronic inflammation and lung damage in tuberculosis (TB). However, circulating metabolites do not always replicate lung-associated biomarkers that define the pathobiology of the disease. The objective of this study was to determine the utility of exhaled breath condensate (EBC), a non-invasive and straightforward sample, to evaluate alveolar space-derived metabolites of redox state and inflammation. We assessed the levels of exhaled oxidant/antioxidant parameters (8-isoprostane, MDA, GSH), inflammatory markers, such as nucleosomes, cytokines (IL-2, IL-4, IL-6 and IL-8, IL-10, GM-CSF, TNF-α, and IFN-γ) and lipid mediators (PGE2, LTB4, RvD1, and Mar1), in patients with recently diagnosed pulmonary TB and healthy controls' EBC and serum. The TB patients showed 36% lower GSH levels, and 2-, 1.4-, 1.1-, and 50-fold higher levels of 8-isoprostanes, nucleosomes, IL-6, and LTB4, respectively, in EBC. There was no correlation between EBC and serum, highlighting the importance of measuring local biomarkers. Quantitation of local inflammatory molecules and redox states in EBC would help find biomarkers useful for pharmacological and follow-up studies in pulmonary tuberculosis.

10.
Infect Drug Resist ; 14: 929-946, 2021.
Artículo en Inglés | MEDLINE | ID: mdl-33727834

RESUMEN

The diagnosis of tuberculosis (TB) in children is difficult because of the low sensitivity and specificity of traditional microbiology techniques in this age group. Whereas in adults the culture of Mycobacterium tuberculosis (M. tuberculosis), the gold standard test, detects 80% of positive cases, it only detects around 30-40% of cases in children. The new methods based on the immune response to M. tuberculosis infection could be affected by many factors. It is necessary to evaluate the medical record, clinical features, presence of drug-resistant M. tuberculosis strains, comorbidities, and BCG vaccination history for the diagnosis in children. There is no ideal biomarker for all TB cases in children. A new strategy based on personalized diagnosis could be used to evaluate specific molecules produced by the host immune response and make therapeutic decisions in each child, thereby changing standard immunological signatures to personalized signatures in TB. In this way, immune diagnosis, prognosis, and the use of potential immunomodulators as adjunct TB treatments will meet personalized treatment.

11.
Int J Mol Sci ; 23(1)2021 Dec 28.
Artículo en Inglés | MEDLINE | ID: mdl-35008755

RESUMEN

In mycobacterial infections, the number of cells from two newly discovered subpopulations of CD3+ myeloid cells are increased at the infection site; one type expresses the T cell receptor (CD3+TCRαß+) and the other does not (CD3+TCRαß-). The role of Mycobacterium tuberculosis (Mtb) virulence in generating these subpopulations and the ability of these cells to migrate remains unclear. In this study, monocyte-derived macrophages (MDMs) infected in vitro with either a virulent (H37Rv) or an avirulent (H37Ra) Mtb strain were phenotypically characterized based on three MDM phenotypes (CD3-, CD3+TCRαß+, and CD3+TCRαß-); then, their migration ability upon Mtb infection was evaluated. We found no differences in the frequency of CD3+ MDMs at 24 h of infection with either Mtb strain. However, H37Rv infection increased the frequency of CD3+TCRαß+ MDMs at a multiplicity of infection of 1 and altered the expression of CD1b, CD1c, and TNF on the surface of cells from both the CD3+ MDM subpopulations; it also modified the expression of CCR2, CXCR1, and CCR7, thus affecting CCL2 and IL-8 levels. Moreover, H37Rv infection decreased the migration ability of the CD3- MDMs, but not CD3+ MDMs. These results confirm that the CD3+ macrophage subpopulations express chemokine receptors that respond to chemoattractants, facilitating cell migration. Together, these data suggest that CD3+ MDMs are a functional subpopulation involved in the immune response against Mtb.


Asunto(s)
Complejo CD3/metabolismo , Movimiento Celular , Macrófagos/citología , Macrófagos/metabolismo , Mycobacterium tuberculosis/fisiología , Receptores de Antígenos de Linfocitos T/metabolismo , Microambiente Celular , Humanos , Inflamación/patología , Ligandos , Modelos Biológicos , Monocitos/metabolismo , Mycobacterium tuberculosis/patogenicidad , Fenotipo , Receptores de Quimiocina/metabolismo , Receptores del Factor de Necrosis Tumoral/genética , Receptores del Factor de Necrosis Tumoral/metabolismo , Tuberculosis/inmunología , Tuberculosis/microbiología , Tuberculosis/patología , Factor de Necrosis Tumoral alfa/genética , Factor de Necrosis Tumoral alfa/metabolismo , Virulencia
12.
Front Immunol ; 11: 2006, 2020.
Artículo en Inglés | MEDLINE | ID: mdl-33013856

RESUMEN

Latent tuberculosis infection (LTBI) is a subclinical mycobacterial infection defined on the basis of cellular immune response to mycobacterial antigens. The tuberculin skin test (TST) and the interferon gamma release assay (IGRA) are currently used to establish the diagnosis of LTB. However, neither TST nor IGRA is useful to discriminate between active and latent tuberculosis. Moreover, these tests cannot be used to predict whether an individual with LTBI will develop active tuberculosis (TB) or whether therapy for LTBI could be effective to decrease the risk of developing active TB. Therefore, in this article, we review current approaches and some efforts to identify an immunological marker that could be useful in distinguishing LTBI from TB and in evaluating the effectiveness of treatment of LTB on the risk of progression to active TB.


Asunto(s)
Tuberculosis Latente/diagnóstico , Mycobacterium tuberculosis/fisiología , Animales , Biomarcadores/metabolismo , Diagnóstico Diferencial , Progresión de la Enfermedad , Humanos , Interferón gamma/metabolismo , Riesgo , Prueba de Tuberculina
14.
J Immunol Res ; 2019: 1297131, 2019.
Artículo en Inglés | MEDLINE | ID: mdl-31886294

RESUMEN

BACKGROUND: The treatment of latent tuberculosis infection (LTBI) in individuals at risk of reactivation is essential for tuberculosis control. However, blood biomarkers associated with LTBI treatment have not been identified. METHODS: Blood samples from tuberculin skin test (TST) reactive individuals were collected before and after one and six months of isoniazid (INH) therapy. Peripheral mononuclear cells (PBMC) were isolated, and an in-house interferon-γ release assay (IGRA) was performed. Expression of chemokine ligand 4 (CCL4), chemokine ligand 10 (CXCL10), chemokine ligand 11 (CXCL11), interferon alpha (IFNA), radical S-adenosyl methionine domain-containing 2 (RSAD2), ubiquitin-specific peptidase 18 (USP18), interferon-induced protein 44 (IFI44), interferon-induced protein 44 like (IFI44L), interferon-induced protein tetratricopeptide repeats 1(IFIT1), and interleukin 2 receptor subunit alpha (IL2RA) mRNA levels were assessed by qPCR before, during, and after INH treatment. RESULTS: We observed significantly lower relative abundances of USP18, IFI44L, IFNA, and IL2RA transcripts in PBMC from IGRA-positive individuals compared to levels in IGRA-negative individuals before INH therapy. Also, relative abundance of CXCL11 was significantly lower in IGRA-positive than in IGRA-negative individuals before and after one month of INH therapy. However, the relative abundance of CCL4, CXCL10, and CXCL11 mRNA was significantly decreased and that of IL2RA and USP18 significantly increased after INH therapy, regardless of the IGRA result. Our results show that USP18, IFI44L, IFIT1, and IL2RA relative abundances increased significantly, meanwhile the relative abundance of CCL4, CXCL11, and IFNA decreased significantly after six months of INH therapy in TST-positive individuals. CONCLUSIONS: Changes in the profiles of USP18, IL2RA, IFNA, CCL4, and CXCL11 expressions during INH treatment in TST-positive individuals, regardless of IGRA status, are potential tools for monitoring latent tuberculosis treatment.


Asunto(s)
Expresión Génica , Subunidad alfa del Receptor de Interleucina-2/genética , Tuberculosis Latente/genética , Tuberculosis Latente/microbiología , Ubiquitina Tiolesterasa/genética , Adulto , Antituberculosos/farmacología , Antituberculosos/uso terapéutico , Biomarcadores , Femenino , Humanos , Ensayos de Liberación de Interferón gamma , Subunidad alfa del Receptor de Interleucina-2/metabolismo , Isoniazida/farmacología , Isoniazida/uso terapéutico , Tuberculosis Latente/diagnóstico , Tuberculosis Latente/tratamiento farmacológico , Leucocitos Mononucleares/efectos de los fármacos , Leucocitos Mononucleares/metabolismo , Masculino , Persona de Mediana Edad , Prueba de Tuberculina , Ubiquitina Tiolesterasa/metabolismo , Adulto Joven
15.
Artículo en Inglés | MEDLINE | ID: mdl-31731429

RESUMEN

Tuberculosis (TB) and air pollution both contribute significantly to the global burden of disease. Epidemiological studies show that exposure to household and urban air pollution increase the risk of new infections with Mycobacterium tuberculosis (M.tb) and the development of TB in persons infected with M.tb and alter treatment outcomes. There is increasing evidence that particulate matter (PM) exposure weakens protective antimycobacterial host immunity. Mechanisms by which exposure to urban PM may adversely affect M.tb-specific human T cell functions have not been studied. We, therefore, explored the effects of urban air pollution PM2.5 (aerodynamic diameters ≤2.5µm) on M.tb-specific T cell functions in human peripheral blood mononuclear cells (PBMC). PM2.5 exposure decreased the capacity of PBMC to control the growth of M.tb and the M.tb-induced expression of CD69, an early surface activation marker expressed on CD3+ T cells. PM2.5 exposure also decreased the production of IFN-γ in CD3+, TNF-α in CD3+ and CD14+ M.tb-infected PBMC, and the M.tb-induced expression of T-box transcription factor TBX21 (T-bet). In contrast, PM2.5 exposure increased the expression of anti-inflammatory cytokine IL-10 in CD3+ and CD14+ PBMC. Taken together, PM2.5 exposure of PBMC prior to infection with M.tb impairs critical antimycobacterial T cell immune functions.


Asunto(s)
Mycobacterium tuberculosis/inmunología , Material Particulado/análisis , Material Particulado/metabolismo , Linfocitos T/efectos de los fármacos , Linfocitos T/inmunología , Adulto , Contaminación del Aire/análisis , Ciudades , Citocinas/metabolismo , Pruebas Diagnósticas de Rutina , Femenino , Humanos , Leucocitos Mononucleares/metabolismo , Masculino , Persona de Mediana Edad , Adulto Joven
16.
PLoS One ; 14(7): e0219122, 2019.
Artículo en Inglés | MEDLINE | ID: mdl-31295271

RESUMEN

Exposure to air pollution particulate matter (PM) and tuberculosis (TB) are two of the leading global public health challenges affecting low and middle income countries. An estimated 4.26 million premature deaths are attributable to household air pollution and an additional 4.1 million to outdoor air pollution annually. Mycobacterium tuberculosis (M.tb) infects a large proportion of the world's population with the risk for TB development increasing during immunosuppressing conditions. There is strong evidence that such immunosuppressive conditions develop during household air pollution exposure, which increases rates of TB development. Exposure to urban air pollution has been shown to alter the outcome of TB therapy. Here we examined whether in vitro exposure to urban air pollution PM alters human immune responses to M.tb. PM2.5 and PM10 (aerodynamic diameters <2.5µm, <10µm) were collected monthly from rainy, cold-dry and warm-dry seasons in Iztapalapa, a highly populated TB-endemic municipality of Mexico City with elevated outdoor air pollution levels. We evaluated the effects of seasonality and size of PM on cytotoxicity and antimycobacterial host immunity in human peripheral blood mononuclear cells (PBMC) from interferon gamma (IFN-γ) release assay (IGRA)+ and IGRA- healthy study subjects. PM10 from cold-dry and warm-dry seasons induced the highest cytotoxicity in PBMC. With the exception of PM2.5 from the cold-dry season, pre-exposure to all seasonal PM reduced M.tb phagocytosis by PBMC. Furthermore, M.tb-induced IFN-γ production was suppressed in PM2.5 and PM10-pre-exposed PBMC from IGRA+ subjects. This observation coincides with the reduced expression of M.tb-induced T-bet, a transcription factor regulating IFN-γ expression in T cells. Pre-exposure to PM10 compared to PM2.5 led to greater loss of M.tb growth control. Exposure to PM2.5 and PM10 collected in different seasons differentially impairs M.tb-induced human host immunity, suggesting biological mechanisms underlying altered M.tb infection and TB treatment outcomes during air pollution exposures.


Asunto(s)
Contaminantes Atmosféricos/toxicidad , Citotoxicidad Inmunológica/efectos de los fármacos , Mycobacterium tuberculosis/inmunología , Mycobacterium tuberculosis/patogenicidad , Material Particulado/toxicidad , Adolescente , Adulto , Anciano , Ciudades , Exposición a Riesgos Ambientales/efectos adversos , Femenino , Interacciones Microbiota-Huesped/efectos de los fármacos , Interacciones Microbiota-Huesped/inmunología , Humanos , Técnicas In Vitro , Interferón gamma/biosíntesis , Interleucina-1beta/biosíntesis , Leucocitos Mononucleares/efectos de los fármacos , Leucocitos Mononucleares/inmunología , Masculino , México , Persona de Mediana Edad , Mycobacterium tuberculosis/crecimiento & desarrollo , Tamaño de la Partícula , Fagocitosis/efectos de los fármacos , Estaciones del Año , Proteínas de Dominio T Box/inmunología , Salud Urbana , Adulto Joven
17.
Thorax ; 74(7): 675-683, 2019 07.
Artículo en Inglés | MEDLINE | ID: mdl-31036772

RESUMEN

RATIONALE: Associations between urban (outdoor) airborne particulate matter (PM) exposure and TB and potential biological mechanisms are poorly explored. OBJECTIVES: To examine whether in vivo exposure to urban outdoor PM in Mexico City and in vitro exposure to urban outdoor PM2.5 (< 2.5 µm median aerodynamic diameter) alters human host immune cell responses to Mycobacterium tuberculosis. METHODS: Cellular toxicity (flow cytometry, proliferation assay (MTS assay)), M. tuberculosis and PM2.5 phagocytosis (microscopy), cytokine-producing cells (Enzyme-linked immune absorbent spot (ELISPOT)), and signalling pathway markers (western blot) were examined in bronchoalveolar cells (BAC) and peripheral blood mononuclear cells (PBMC) from healthy, non-smoking, residents of Mexico City (n=35; 13 female, 22 male). In vivo-acquired PM burden in alveolar macrophages (AM) was measured by digital image analysis. MEASUREMENTS AND MAIN RESULTS: In vitro exposure of AM to PM2.5 did not affect M. tuberculosis phagocytosis. High in vivo-acquired AM PM burden reduced constitutive, M. tuberculosis and PM-induced interleukin-1ß production in freshly isolated BAC but not in autologous PBMC while it reduced constitutive production of tumour necrosis factor-alpha in both BAC and PBMC. Further, PM burden was positively correlated with constitutive, PM, M. tuberculosis and purified protein derivative (PPD)-induced interferon gamma (IFN-γ) in BAC, and negatively correlated with PPD-induced IFN-γ in PBMC. CONCLUSIONS: Inhalation exposure to urban air pollution PM impairs important components of the protective human lung and systemic immune response against M. tuberculosis. PM load in AM is correlated with altered M. tuberculosis-induced cytokine production in the lung and systemic compartments. Chronic PM exposure with high constitutive expression of proinflammatory cytokines results in relative cellular unresponsiveness.


Asunto(s)
Pulmón/inmunología , Mycobacterium tuberculosis/inmunología , Material Particulado/efectos adversos , Salud Urbana/estadística & datos numéricos , Adulto , Líquido del Lavado Bronquioalveolar/inmunología , Supervivencia Celular/efectos de los fármacos , Supervivencia Celular/inmunología , Citocinas/biosíntesis , Exposición a Riesgos Ambientales/efectos adversos , Exposición a Riesgos Ambientales/análisis , Femenino , Citometría de Flujo/métodos , Interacciones Microbiota-Huesped/inmunología , Humanos , Mediadores de Inflamación/metabolismo , Masculino , México , Persona de Mediana Edad , Tamaño de la Partícula , Material Particulado/análisis , Material Particulado/farmacología , Fagocitosis/efectos de los fármacos , Fagocitosis/inmunología , Adulto Joven
18.
Am J Med Sci ; 357(3): 184-194, 2019 03.
Artículo en Inglés | MEDLINE | ID: mdl-30797501

RESUMEN

Phagocytosis is necessary for antigen degradation and presentation, the activation of the adaptive immune response and the elimination of pathogenic micro-organisms. The phagosomal vacuole formed during phagocytosis requires a process of maturation that involves fusion with lysosomes, a decrease in luminal pH and the activation of the enzymes that eventually will destroy phagocytized micro-organisms. Tuberculosis is an infectious disease caused by Mycobacterium tuberculosis. This agent has developed various strategies to prevent phagosome maturation and persist indefinitely in latency mode. Herein, we review these strategies in the light of available experimental evidence. A better understanding of them may be essential in the development of more effective therapies against tuberculosis.


Asunto(s)
Inmunidad Adaptativa/fisiología , Evasión Inmune , Mycobacterium tuberculosis/fisiología , Fagocitosis/fisiología , Humanos , Lisosomas/inmunología , Fagosomas/inmunología
19.
Front Oncol ; 9: 1429, 2019.
Artículo en Inglés | MEDLINE | ID: mdl-31921681

RESUMEN

Purpose: Hereditary Breast and Ovarian Cancer (HBOC) syndrome is responsible for ~5-10% of all diagnosed breast and ovarian cancers. Breast cancer is the most common malignancy and the leading cause of cancer-related mortality among women in Latin America (LA). The main objective of this study was to develop a comprehensive understanding of the genomic epidemiology of HBOC throughout the establishment of The Latin American consortium for HBOC-LACAM, consisting of specialists from 5 countries in LA and the description of the genomic results from the first phase of the study. Methods: We have recruited 403 individuals that fulfilled the criteria for HBOC from 11 health institutions of Argentina, Colombia, Guatemala, Mexico and Peru. A pilot cohort of 222 individuals was analyzed by NGS gene panels. One hundred forty-three genes were selected on the basis of their putative role in susceptibility to different hereditary cancers. Libraries were sequenced in MiSeq (Illumina, Inc.) and PGM (Ion Torrent-Thermo Fisher Scientific) platforms. Results: The overall prevalence of pathogenic variants was 17% (38/222); the distribution spanned 14 genes and varied by country. The highest relative prevalence of pathogenic variants was found in patients from Argentina (25%, 14/57), followed by Mexico (18%, 12/68), Guatemala (16%, 3/19), and Colombia (13%, 10/78). Pathogenic variants were found in BRCA1 (20%) and BRCA2 (29%) genes. Pathogenic variants were found in other 12 genes, including high and moderate risk genes such as MSH2, MSH6, MUTYH, and PALB2. Additional pathogenic variants were found in HBOC unrelated genes such as DCLRE1C, WRN, PDE11A, and PDGFB. Conclusion: In this first phase of the project, we recruited 403 individuals and evaluated the germline genetic alterations in an initial cohort of 222 patients among 4 countries. Our data show for the first time in LA the distribution of pathogenic variants in a broad set of cancer susceptibility genes in HBOC. Even though we used extended gene panels, there was still a high proportion of patients without any detectable pathogenic variant, which emphasizes the larger, unexplored genetic nature of the disease in these populations.

20.
Front Immunol ; 8: 1659, 2017.
Artículo en Inglés | MEDLINE | ID: mdl-29230224

RESUMEN

Lipoarabinomannan (LAM) is a lipid virulent factor secreted by Mycobacterium tuberculosis (Mtb). LAM can be found in the sputum and urine of patients with active tuberculosis. When human monocytes are differentiated into macrophages [monocyte-derived macrophages (MDM)] in the presence of LAM, MDM are poorly functional which may limit the immune response to Mtb infection. Our previous studies have shown that TIM3 and galectin (GAL)9 interaction induces anti-mycobacterial activity, and the expression levels of TIM3 and GAL9 are downregulated during Mtb infection. We postulated that LAM affects GAL9/TIM3 pathway, and, in consequence, the ability of the macrophage to control bacterial growth could be affected. In this work, we have generated MDM in the presence of LAM and observed that the expression of TIM3 was not affected; in contrast, GAL9 expression was downregulated at the transcriptional and protein levels. We observed that the cell surface and the soluble form of tumor necrosis factor (TNF) receptor 2 were decreased. We also found that when LAM-exposed MDM were activated with LPS, they produced less TNF, and the transcription factor proteinase-activated receptor-2 (PAR2), which is involved in host immune responses to infection, was not induced. Our data show that LAM-exposed MDM were deficient in the control of intracellular growth of Mtb. In conclusion, LAM-exposed MDM leads to MDM with impaired intracellular signal activation affecting GAL9, TNF, and PAR2 pathways, which are important to restrict Mtb growth.

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