Immunoendocrine interactions during HIV-TB coinfection: implications for the design of new adjuvant therapies

Adrenalitis tuberculosa: a propósito de una actualización

Introducción: la insuficiencia suprarrenal primaria (IA) descrita por Thomas Addison en 1855 atribuía como principal causa a la infección por tuberculosis (TBC) diseminada, pero con el paso del tiempo ha disminuido en los países desarrollados. En aquellos en vías de desarrollo se mantiene alta esta etiología infecciosa, en especial en pacientes con VIH. Objetivo: realizar una revisión narrativa de la literatura reciente sobre la adrenalitis TBC, incluyendo el enfoque, manejo y seguimiento en los casos de insuficiencia suprarrenal primaria (IA). Materiales y métodos:  búsqueda y análisis de los artículos disponibles en los últimos 5 años bajo los descriptores en ciencias de la salud (DeCS) enfermedad de Addison, tuberculosis, insuficiencia suprarrenal primaria y adrenalitis en español en las bases de Google scholar y LILACS, y en inglés en PubMed y ClinicalKey. Conclusiones:  la insuficiencia adrenal o adrenalitis por TBC ha descendido como causa de IA primaria, pero en el contexto de reemergencia de infección por VIH, continúa siendo una causa importante de IA en países en desarrollo. En estos casos además de la suplencia con corticosteroides el tratamiento de la causa específica es de importancia para impactar en la respuesta clínica, la supervivencia y la calidad de vida.

The Association of Tuberculosis Mono-infection and Tuberculosis-Human Immunodeficiency Virus (TB-HIV) Co-infection in the Pathogenesis of Hypertensive Disorders of Pregnancy

PURPOSE OF REVIEW

This review highlights the impact of TB mono-infection and TB-HIV co-infection on the pathogenesis of adverse maternal outcomes such as hypertensive disorders of pregnancy (HDP) and adverse fetal outcomes such as recurrent spontaneous abortion (RSA), fetal growth restriction (FGR), and low birth weight.

RECENT FINDINGS

Research has shown that HDP, such as severe pre-eclampsia (PE) and eclampsia, as well as adverse fetal outcomes such as recurrent spontaneous abortion, fetal growth restriction, and low birth weight, are higher in women diagnosed with TB mono-infection and even higher in TB-HIV co-infection compared to those without TB. This is speculated to occur due to exaggerated activation of both angiogenic factors such as vascular endothelial growth factor (VEGF), nitric oxide (NO), angiotensin 2, (Ang 2), intracellular adhesion molecules (ICAMs), and inflammatory cytokines such as interleukin 2 (IL-2), (IL-17), and interferon-gamma (INF-γ). There is a lack of information with regard to the pathogenesis of adverse maternal and fetal outcomes upon TB mono-infection and TB-HIV co-infection; therefore, further investigations on the impact of TB mono-infection and TB-HIV co-infection on adverse maternal and fetal outcomes are urgently needed. This will assist in improving diagnostic procedures in pregnant women affected with TB as wells as TB-HIV co-infection.

7-oxo-DHEA enhances impaired M. tuberculosis-specific T cell responses during HIV-TB coinfection

BACKGROUND

Mycobacterium tuberculosis (Mtb) is the causative agent of tuberculosis (TB), affecting approximately one third of the world's population. Development of an adequate immune response will determine disease progression or progress to chronic infection. Risk of developing TB among human immunodeficiency virus (HIV)-coinfected patients (HIV-TB) is 20-30 times higher than those without HIV infection, and a synergistic interplay between these two pathogens accelerates the decline in immunological functions. TB treatment in HIV-TB coinfected persons is challenging and it has a prolonged duration, mainly due to the immune system failure to provide an adequate support for the therapy. Therefore, we aimed to study the role of the hormone 7-oxo-dehydroepiandrosterone (7-OD) as a modulator of anti-tuberculosis immune responses in the context of HIV-TB coinfection.

METHODS

A cross-sectional study was conducted among HIV-TB patients and healthy donors (HD). We characterized the ex vivo phenotype of CD4 + T cells and also evaluated in vitro antigen-specific responses by Mtb stimulation of peripheral blood mononuclear cells (PBMCs) in the presence or absence of 7-OD. We assessed lymphoproliferative activity, cytokine production and master transcription factor profiles.

RESULTS

Our results show that HIV-TB patients were not able to generate successful anti-tubercular responses in vitro compared to HD, as reduced IFN-γ/IL-10 and IFN-γ/IL-17A ratios were observed. Interestingly, treatment with 7-OD enhanced Th1 responses by increasing Mtb-induced proliferation and the production of IFN-γ and TNF-α over IL-10 levels. Additionally, in vitro Mtb stimulation augmented the frequency of cells with a regulatory phenotype, while 7-OD reduced the proportion of these subsets and induced an increase in CD4 + T-bet+ (Th1) subpopulation, which is associated with clinical data linked to an improved disease outcome.

CONCLUSIONS

We conclude that 7-OD modifies the cytokine balance and the phenotype of CD4 + T cells towards a more favorable profile for mycobacteria control. These results provide new data to delineate novel treatment approaches as co-adjuvant for the treatment of TB.

Methods and quality of disease models incorporating more than two sexually transmitted infections: a protocol for a systematic review of the evidence

INTRODUCTION

Disease models can be useful tools for policy makers to inform their decisions. They can help to estimate the costs and benefits of interventions without conducting clinical trials and help to extrapolate the findings of clinical trials to a population level.Sexually transmitted infections (STIs) do not operate in isolation. Risk-taking behaviours and biological interactions can increase the likelihood of an individual being coinfected with more than one STI.Currently, few STI models consider coinfection or the interaction between STIs. We aim to identify and summarise STI models for two or more STIs and describe their modelling approaches.

METHODS AND ANALYSIS

Six databases (Cochrane, Embase, PLOS, ProQuest, Medline and Web of Science) were searched on 27 November 2018 to identify studies that focus on the reporting of the methodology and quality of models for at least two different STIs. The quality of all eligible studies will be accessed using a percentage scale published by Kopec et al . We will summarise all used approaches to model two or more STIs in one model. The Preferred Reporting Items for Systematic Reviews and Meta-Analyses (PRISMA) framework will be used to report all outcomes.

ETHICS AND DISSEMINATION

Ethical approval is not required for this systematic review. The results of this review will be published in a peer-reviewed journal and presented at a suitable conference. The findings from this review will be used to inform the development of a new multi-STI model.

PROSPERO REGISTRATION NUMBER

CRD42017076837.

Determination of dehydroepiandrosterone and its biologically active oxygenated metabolites in human plasma evinces a hormonal imbalance during HIV-TB coinfection

An estimated one third of the world's population is affected by latent tuberculosis (TB), which once active represents a leading cause of death among infectious diseases. Human immunodeficiency virus (HIV) infection is a main predisposing factor to TB reactivation. Individuals HIV-TB co-infected develop a chronic state of inflammation associated with hypothalamic-pituitary-adrenal (HPA) axis dysregulation. This results in a hormonal imbalance, disturbing the physiological levels of cortisol and dehydroepiandrosterone (DHEA). DHEA and its oxygenated metabolites androstenediol (AED), androstenetriol (AET) and 7-oxo-DHEA are immunomodulatory compounds that may regulate physiopathology in HIV-TB co-infection. In order to study possible changes in plasma levels of these hormones, we developed an approach based on high performance liquid chromatography-tandem mass spectrometry (HPLC-MS/MS). To our knowledge, this represents the first report of their simultaneous measurement in HIV-TB individuals and the comparison with healthy donors, obtaining statistically higher plasma levels of DHEA, AET and 7-oxo-DHEA in patients. Moreover, we found that concentrations of 7-oxo-DHEA positively correlated with absolute CD4+ T cell counts, nadir CD4+ T cell values and with individuals who presented TB restricted to the lungs. This research contributes to understanding the role of these hormones in HIV-TB and emphasizes the importance of deepening their study in this context.

Expression, purification and characterization of Esx-1 secretion-associated protein EspL from Mycobacterium tuberculosis

The Esx-1 cluster encodes a special secretion system that is important for granuloma formation and virulence when Mycobacterium tuberculosis infects the host. As one of the 'core' genes in the cluster, Rv3880c gene codes an Esx-1 secretion-associated protein EspL from Mycobacterium tuberculosis (MtEspL). It has been reported that EspL had a strong influence on the secretion of other two virulence factors, EsxA and EspE. However, so far little is known about the tertiary structure and specific function of MtEspL due to the difficulty in preparing the high-quality protein. In this study, we tried several fusion tags and various expression conditions to recombinantly express MtEspL. Through a four-step purification procedure, ultimately, we successfully prepared the full-length MtEspL in Escherichia coli BL21 (DE3) with a purity of 98%. The yields of the purified MtEspL protein were 14 mg/L in Luria Bertani medium and 5.6 mg/L in M9 minimal medium, respectively. Biophysical experiments showed that MtEspL existed in a dimeric form. Moreover, the (1)H-(15)N HSQC spectrum recorded on MtEspL illustrates a favorable dispersion of the resonance peaks, indicating that the symmetric dimeric MtEspL adopted a well-folded structure and might be feasible to determine its solution structure by NMR spectroscopy. Moreover, we identified a strong DNA-binding ability of MtEspL with fluorescence quenching experiments. Our work lays the basis for further structural determination and functional exploration of MtEspL.