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1.
Open Forum Infect Dis ; 10(3): ofad128, 2023 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-36998631

RESUMO

Background: To better understand the pathogenesis of pericardial tuberculosis (PCTB), we sought to characterize the systemic inflammatory profile in people with human immunodeficiency virus type 1 (HIV-1) with latent TB infection (LTBI), pulmonary TB (PTB), or PCTB. Methods: Using Luminex, we measured the concentration of 39 analytes in pericardial fluid (PCF) and paired plasma from 18 PCTB participants, and plasma from 16 LTBI and 20 PTB participants. Follow-up plasma samples were also obtained from PTB and PCTB participants. HLA-DR expression on Mycobacterium tuberculosis-specific CD4 T cells was measured in baseline samples using flow cytometry. Results: Assessment of the overall systemic inflammatory profile by principal component analysis showed that the inflammatory profile of active TB participants was distinct from the LTBI group, while PTB patients could not be distinguished from those with PCTB. When comparing the inflammatory profile between PCF and paired blood, we found that the concentrations of most analytes (25/39) were elevated at site of disease. However, the inflammatory profile in PCF partially mirrored inflammatory events in the blood. After TB treatment completion, the overall plasma inflammatory profile reverted to that observed in the LTBI group. Lastly, HLA-DR expression showed the best performance for TB diagnosis compared to previously described biosignatures built from soluble markers. Conclusions: Our results show that the inflammatory profile in blood was comparable between PTB and PCTB. However, at the site of infection (PCF), inflammation was significantly elevated compared to blood. Additionally, our data emphasize the potential role of HLA-DR expression as a biomarker for TB diagnosis.

3.
Front Immunol ; 13: 1009016, 2022.
Artigo em Inglês | MEDLINE | ID: mdl-36439130

RESUMO

Studies of the immune response at the site of disease in extra-pulmonary tuberculosis (EPTB) disease are scarce. In this study, we compared the cellular profile of Mycobacterium tuberculosis (Mtb)-specific T cells in pericardial fluid and peripheral blood in patients with pericardial TB (PCTB). Whole blood and pericardial fluid (PCF) samples were collected at the time of diagnostic sampling, with repeat blood sampling after completion of anti-tubercular treatment (ATT) in 16 PCTB patients, most of them being HIV-1 infected (n=14). These samples were stimulated ex vivo and the phenotypic and functional cellular profile of PCF and blood was assessed by flow cytometry. We found that lymphocytes were the predominant cell type in PCF in PCTB, with a preferential influx of CD4 T cells. The frequencies of TNF-α producing Mtb-specific granulocytes and Mtb-specific CD4 T cells were significantly higher in PCF compared to blood. Mtb-specific CD4 T cells in PCF exhibited a distinct phenotype compared to those in blood, with greater GrB expression and lower CD27 and KLRG1 expression. We observed no difference in the production IFNγ, TNF or IL-2 by Mtb-specific CD4 T cells between the two compartments, but MIP-1ß production was lower in the PCF T cells. Bacterial loads were not associated with alterations in the phenotype or function of Mtb-specific CD4 T cells. Upon ATT completion, HLA-DR, Ki-67 and GrB expression was significantly decreased, and relative IL-2 production was increased in peripheral Mtb-specific CD4 T cells. Overall, using an ex vivo assay to compare the immune response towards Mtb in PCF and in blood, we identified significant difference in the phenotypic profile of Mtb-specific CD4 T response between these two compartments. Moreover, we show that the activation profile of peripheral Mtb-specific CD4 T cells could be used to monitor treatment response in PCTB.


Assuntos
Mycobacterium tuberculosis , Tuberculose dos Linfonodos , Humanos , Linfócitos T CD4-Positivos , Interleucina-2/metabolismo , Fenótipo
4.
J Int AIDS Soc ; 24(3): e25671, 2021 03.
Artigo em Inglês | MEDLINE | ID: mdl-33719199

RESUMO

INTRODUCTION: There are limited data on Tuberculosis (TB) in adolescents with perinatally acquired HIV (APHIV). We examined the incidence and determinants of TB infection and disease in the Cape Town Adolescent Antiretroviral Cohort (CTAAC). METHODS: Youth between nine and fourteen years on antiretroviral therapy (ART) for more than six months in public sector care, and age-matched HIV-negative adolescents, were enrolled between July 2013 through March 2015 and followed six-monthly. Data were censored on 31 October 2018. Symptom screening, chest radiograph, viral load, CD4 count, QuantiFERON (QFT) and sputum for Xpert MTB/RIF, microscopy, culture and sensitivity were performed annually. TB infection was defined by a QFT of >0.35 IU/mL. TB diagnosis was defined as confirmed (culture or Xpert MTB/RIF positive) or unconfirmed (clinical diagnosis and started on TB treatment). Analyses examined the incidence and determinants of TB infection and disease. RESULTS: Overall 496 HIV+ and 103 HIV-negative participants (median age at enrolment 12 years (interquartile range, IQR 10.6 to 13.3) were followed for a median of 3.1 years (IQR 3.0 to 3.4); 50% (298/599) were male. APHIV initiated ART at median age 4.4 years (IQR 2.1 to 7.6). At enrolment, 376/496 (76%) had HIV viral load <40 copies/mL, median CD4 count was 713 cells/mm3 and 179/559 (32%) were QFT+, with no difference by HIV status (APHIV 154/468, 33%; HIV negative 25/91, 27%; p = 0.31). The cumulative QFT+ prevalence was similar (APHIV 225/492, 46%; 95%CI 41% to 50%; HIV negative 44/98, 45%; 95% CI 35% to 55%; p = 0.88). APHIV had a higher incidence of all TB disease than HIV-negative adolescents (2.2/100PY, 95% CI 1.6 to 3.1 vs. 0.3/100PY, 95% CI 0.04 to 2.2; IRR 7.36, 95% CI 1.01 to 53.55). The rate of bacteriologically confirmed TB in APHIV was 1.3/100 PY compared to 0.3/100PY for HIV-negative adolescents, suggesting a fourfold increased risk of developing TB disease in APHIV despite access to ART. In addition, a positive QFT at enrolment was not predictive of TB in this population. CONCLUSIONS: High incidence rates of TB disease occur in APHIV despite similar QFT conversion rates to HIV-negative adolescents. Strategies to prevent TB in this vulnerable group must be strengthened.


Assuntos
Coinfecção/epidemiologia , Infecções por HIV/complicações , Tuberculose/epidemiologia , Adolescente , Terapia Antirretroviral de Alta Atividade , Pré-Escolar , Estudos de Coortes , Feminino , Infecções por HIV/tratamento farmacológico , Infecções por HIV/epidemiologia , Humanos , Incidência , Masculino , África do Sul/epidemiologia , Tuberculose/diagnóstico
5.
Mucosal Immunol ; 14(2): 491-499, 2021 03.
Artigo em Inglês | MEDLINE | ID: mdl-32678272

RESUMO

Recent data from mice and non-human primate models of tuberculosis suggested that CD153, a TNF super family member, plays an important role in Mycobacterium tuberculosis (Mtb) control. However, this molecule has not been comprehensively evaluated in humans. Here, we show that the proportion of Mtb-specific CD4 T cells expressing CD153 was significantly reduced in active TB patients compared to latently infected persons. Importantly, the CD153+ Mtb-specific CD4 response inversely correlated with lung bacterial load, inferred by Xpert cycle threshold, irrespective of HIV status. Antitubercular treatment partially restored CD153 expression on Mtb-specific CD4 T cells. This is the first report of a subset of Mtb-specific CD4 T cells showing strong negative correlation with bacterial burden. Building on substantial evidence from animal models implicating CD153 as a mediator of host protection, our findings suggest it may play a similar role in humans and its measurement may be useful to evaluate TB vaccine efficacy.


Assuntos
Ligante CD30/metabolismo , Linfócitos T CD4-Positivos/imunologia , Pulmão/imunologia , Mycobacterium tuberculosis/fisiologia , Vacinas contra a Tuberculose/imunologia , Tuberculose Pulmonar/imunologia , Adulto , Animais , Carga Bacteriana , Ligante CD30/genética , Modelos Animais de Doenças , Feminino , Humanos , Pulmão/microbiologia , Masculino , Especificidade do Receptor de Antígeno de Linfócitos T , Adulto Jovem
6.
Clin Transl Immunology ; 9(9): e1176, 2020.
Artigo em Inglês | MEDLINE | ID: mdl-33005414

RESUMO

OBJECTIVES: The development of non-sputum-based assays for tuberculosis (TB) diagnosis and treatment monitoring is a key priority. Recent data indicate that whole blood-based assays to assess the phenotype of Mycobacterium tuberculosis (Mtb)-specific CD4 T cells hold promise for this purpose and require further investigation in well-characterised TB cohorts. In this study, we investigated the relationship between the phenotypic signature of Mtb-specific CD4 responses, TB disease extent and treatment response. METHODS: Using flow cytometry, we measured the expression of phenotypic and functional markers (HLA-DR, CD27, CD153, KLRG1, IL-2, MIP-1ß, TNF-α and IFN-γ) on Mtb-specific CD4 T-cells in whole blood from 161 participants of varying TB and HIV status. TB disease extent was graded as a continuum using the Xpertct value, C-reactive protein, Timika radiographic score and monocyte/lymphocyte ratio. RESULTS: The phenotypic profile of Mtb-specific CD4 T cells pre-anti-tubercular treatment (ATT) strongly correlated with disease extent, irrespective of HIV status. ATT associated with major changes in the phenotype of Mtb-specific CD4 T cells, with decreased expression of HLA-DR and increased CD27 and CD153 expression. Principal component analysis showed an almost complete separation between latent TB infection (LTBI) and active TB (aTB) pre-ATT groups, whereas the profile of the aTB post-ATT group overlapped with the LTBI group. However, in patients experiencing treatment failure or relapse, no significant changes were observed in Mtb-specific CD4 T-cell phenotype pre- and post-ATT. CONCLUSION: Whole blood-based assays of Mtb-specific CD4 T-cell activation and maturation markers can be used as non-sputum-based biomarkers of disease extent and treatment monitoring in TB, regardless of HIV-1 status.

7.
Front Immunol ; 8: 690, 2017.
Artigo em Inglês | MEDLINE | ID: mdl-28674532

RESUMO

A bidirectional communication between the immune and endocrine systems exists and facilitates optimum responses in the host during infections. This is in part achieved through changes in secretion patterns of hypothalamic hormones induced by inflammatory cytokines. The aim of this study was to elucidate the immune-endocrine alterations during tuberculosis (TB) treatment in patients with cured and failed TB treatment outcomes. Blood samples were collected from 27 cured and 10 failed patients and hormone as well as cytokine concentrations quantified at baseline, week 4, and month 6 of TB treatment. Hormone profiles of the two treatment outcome groups were different from each other prior to as well as during TB treatment. Treatment response effects were observed for cortisol, estradiol, T3, T4 ghrelin, leptin, amylin, adiponectin, and dehydroepiandrosterone (DHEA). Trends suggest that T4, amylin, and DHEA concentrations were different between treatment outcomes, although these did not reach statistical significance. Relationships between endocrine and inflammatory markers and the biological pathways involved differed between cured and failed treatment patients. These results highlight the complex interaction between the endocrine and immune system during active TB disease and throughout treatment and suggest that endocrine markers in conjunction with inflammatory markers may be useful in predicting unfavorable treatment outcomes.

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