Understanding the tuberculosis granuloma: the matrix revolutions

Breaking barriers: The potential of nanosystems in antituberculosis therapy

Tuberculosis (TB), caused by Mycobacterium tuberculosis, continues to pose a significant threat to global health. The resilience of TB is amplified by a myriad of physical, biological, and biopharmaceutical barriers that challenge conventional therapeutic approaches. This review navigates the intricate landscape of TB treatment, from the stealth of latent infections and the strength of granuloma formations to the daunting specters of drug resistance and altered gene expression. Amidst these challenges, traditional therapies often fail, contending with inconsistent bioavailability, prolonged treatment regimens, and socioeconomic burdens. Nanoscale Drug Delivery Systems (NDDSs) emerge as a promising beacon, ready to overcome these barriers, offering better drug targeting and improved patient adherence. Through a critical approach, we evaluate a spectrum of nanosystems and their efficacy against MTB both in vitro and in vivo. This review advocates for the intensification of research in NDDSs, heralding their potential to reshape the contours of global TB treatment strategies.

Leveraging insights from cancer to improve tuberculosis therapy

Exploring and exploiting the microenvironmental similarities between pulmonary tuberculosis (TB) granulomas and malignant tumors has revealed new strategies for more efficacious host-directed therapies (HDTs). This opinion article discusses a paradigm shift in TB therapeutic development, drawing on critical insights from oncology. We summarize recent efforts to characterize and overcome key shared features between tumors and granulomas, including excessive fibrosis, abnormal angiogenesis, hypoxia and necrosis, and immunosuppression. We provide specific examples of cancer therapy application to TB to overcome these microenvironmental abnormalities, including matrix-targeting therapies, antiangiogenic agents, and immune-stimulatory drugs. Finally, we propose a new framework for combining HDTs with anti-TB agents to maximize therapeutic delivery and efficacy while reducing treatment dosages, duration, and harmful side effects to benefit TB patients.

Discovering novel biomarkers for diagnosis and treatment monitoring of active pulmonary tuberculosis by ion metabolism analysis

Tuberculosis (TB) is a highly lethal infectious disease that poses a global threat. Timely and accurate biomarker for TB diagnosis and treatment monitoring remains a pressing need. Ions, the crucial trace element for humans, may be potential targets for TB diagnosis and the forecasting of TB development. To explore the potential of ions as biomarkers, we measured and compared the levels of various ions in whole blood and plasma samples from healthy control (HC), pulmonary TB patients (TB), cured pulmonary TB patients (RxTB), and other non-TB pneumonia patients (PN) by using ultra-high performance liquid chromatography-tandem mass spectrometry. Our study demonstrated that Cu (AUC = 0.670), Pb (AUC = 0.660), and Zn (AUC = 0.701) in whole blood exhibited promising diagnostic performance for TB. Then we used a neural network (NNET) for TB prediction, the AUC values used to differentiate definite TB from HC or PN in plasma were 0.867 and 0.864, respectively. The AUC values used to differentiate definite TB from HC or PN in whole blood were 0.818 and 0.660, respectively. Our correlation analysis showed that Zn (r= 0.356, p=0.001) and Cu (r= 0.361, p=0.0004) in plasma are most closely related to disease severity. Additionally, six ions (Cu, Sb, V, Mn, Fe, Sr) in plasma and whole blood were altered following anti-TB therapy. These results showed that ions could be diagnostic biomarkers for TB. Furthermore, the level of particular ions can forecast the degree of lung damage and the success of the TB treatment. In conclusion, this study highlights the possibility of using ions from blood samples to enable rapid tuberculosis diagnosis.

Integrated plasma proteomics identifies tuberculosis-specific diagnostic biomarkers

BACKGROUNDNovel biomarkers to identify infectious patients transmitting Mycobacterium tuberculosis are urgently needed to control the global tuberculosis (TB) pandemic. We hypothesized that proteins released into the plasma in active pulmonary TB are clinically useful biomarkers to distinguish TB cases from healthy individuals and patients with other respiratory infections.METHODSWe applied a highly sensitive non-depletion tandem mass spectrometry discovery approach to investigate plasma protein expression in pulmonary TB cases compared to healthy controls in South African and Peruvian cohorts. Bioinformatic analysis using linear modeling and network correlation analyses identified 118 differentially expressed proteins, significant through 3 complementary analytical pipelines. Candidate biomarkers were subsequently analyzed in 2 validation cohorts of differing ethnicity using antibody-based proximity extension assays.RESULTSTB-specific host biomarkers were confirmed. A 6-protein diagnostic panel, comprising FETUB, FCGR3B, LRG1, SELL, CD14, and ADA2, differentiated patients with pulmonary TB from healthy controls and patients with other respiratory infections with high sensitivity and specificity in both cohorts.CONCLUSIONThis biomarker panel exceeds the World Health Organization Target Product Profile specificity criteria for a triage test for TB. The new biomarkers have potential for further development as near-patient TB screening assays, thereby helping to close the case-detection gap that fuels the global pandemic.FUNDINGMedical Research Council (MRC) (MR/R001065/1, MR/S024220/1, MR/P023754/1, and MR/W025728/1); the MRC and the UK Foreign Commonwealth and Development Office; the UK National Institute for Health Research (NIHR); the Wellcome Trust (094000, 203135, and CC2112); Starter Grant for Clinical Lecturers (Academy of Medical Sciences UK); the British Infection Association; the Program for Advanced Research Capacities for AIDS in Peru at Universidad Peruana Cayetano Heredia (D43TW00976301) from the Fogarty International Center at the US NIH; the UK Technology Strategy Board/Innovate UK (101556); the Francis Crick Institute, which receives funding from UKRI-MRC (CC2112); Cancer Research UK (CC2112); and the NIHR Biomedical Research Centre of Imperial College NHS.

Natural products in anti-tuberculosis host-directed therapy

Given that the disease progression of tuberculosis (TB) is primarily related to the host's immune status, it has been gradually realized that chemotherapy that targets the bacteria may never, on its own, wholly eradicate Mycobacterium tuberculosis, the causative agent of TB. The concept of host-directed therapy (HDT) with immune adjuvants has emerged. HDT could potentially interfere with infection and colonization by the pathogens, enhance the protective immune responses of hosts, suppress the overwhelming inflammatory responses, and help to attain a state of homeostasis that favors treatment efficacy. However, the HDT drugs currently being assessed in combination with anti-TB chemotherapy still face the dilemmas arising from side effects and high costs. Natural products are well suited to compensate for these shortcomings by having gentle modulatory effects on the host immune responses with less immunopathological damage at a lower cost. In this review, we first summarize the profiles of anti-TB immunology and the characteristics of HDT. Then, we focus on the rationale and challenges of developing and implementing natural products-based HDT. A succinct report of the medications currently being evaluated in clinical trials and preclinical studies is provided. This review aims to promote target-based screening and accelerate novel TB drug discovery.

Coccidioidomycosis Granulomas Informed by Other Diseases: Advancements, Gaps, and Challenges

Valley fever is a respiratory disease caused by a soil fungus, Coccidioides, that is inhaled upon soil disruption. One mechanism by which the host immune system attempts to control and eliminate Coccidioides is through granuloma formation. However, very little is known about granulomas during Coccidioides infection. Granulomas were first identified in tuberculosis (TB) lungs as early as 1679, and yet many gaps in our understanding of granuloma formation, maintenance, and regulation remain. Granulomas are best defined in TB, providing clues that may be leveraged to understand Coccidioides infections. Granulomas also form during several other infectious and spontaneous diseases including sarcoidosis, chronic granulomatous disease (CGD), and others. This review explores our current understanding of granulomas, as well as potential mechanisms, and applies this knowledge to unraveling coccidioidomycosis granulomas.

Incidence and Risk of Lung Cancer in Tuberculosis Patients, and Vice Versa: A Literature Review of the Last Decade

Background

The incidence and risk of both lung cancer (LC) and tuberculosis (TB) are increasing rapidly. These two diseases frequently exist together and can influence the incidence and risk of each other. The aim of the current review was to summarize the incidence and risk of LC in TB patients, and vice versa, short out research gap, and contemplate future research perspectives. Methodology. PubMed and Scopus databases, and Google Scholar search engine were searched for epidemiological studies that investigated the incidence and risk of TB and LC, published since January 2011 to April 2022, and written in English. We used the searching keyword "tuberculosis" combined with "lung cancer" and associated medical subject heading (MeSH) to retrieve eligible research articles. We retrieved information's regarding the diagnosis of TB and LC, confounders, the associations of TB and LC, and incidence and risks of each other.

Results

We found higher incidence rate and risks (1.64 to 6 times higher) of LC in TB patients in comparison to non-TB participants. However, the incidence rate and risks of TB in LC patients were comparatively low. Male patients were exhibited higher risks than female. The medical comorbidities, smoking habits, and age can also influence the associations and risks of LC in TB patients or vice versa.

Conclusion

Our summarized studies might suggest that existing active TB may increase the incidence and risk of LC. However, large prospective cohort study is warranted to explore the real scenario worldwide.

An Improved Diagnostic of the Mycobacterium tuberculosis Drug Resistance Status by Applying a Decision Tree to Probabilities Assigned by the CatBoost Multiclassifier of Matrix Metalloproteinases Biomarkers

In this work, we discuss an opportunity to use a set of the matrix metalloproteinases MMP-1, MMP-8, and MMP-9 and the tissue inhibitor TIMP, the concentrations of which can be easily obtained via a blood test from patients suffering from tuberculosis, as the biomarker for a fast diagnosis of the drug resistance status of Mycobacterium tuberculosis. The diagnostic approach is based on machine learning with the CatBoost system, which has been supplied with additional postprocessing. The latter refers not only to the simple probabilities of ML-predicted outcomes but also to the decision tree-like procedure, which takes into account the presence of strict zeros in the primary set of probabilities. It is demonstrated that this procedure significantly elevates the accuracy of distinguishing between sensitive, multi-, and extremely drug-resistant strains.

Immunosuppressive Mechanisms in Brucellosis in Light of Chronic Bacterial Diseases

Brucellosis is considered one of the major zoonoses worldwide, constituting a critical livestock and human health concern with a huge socio-economic burden. Brucella genus, its etiologic agent, is composed of intracellular bacteria that have evolved a prodigious ability to elude and shape host immunity to establish chronic infection. Brucella’s intracellular lifestyle and pathogen-associated molecular patterns, such as its specific lipopolysaccharide (LPS), are key factors for hiding and hampering recognition by the immune system. Here, we will review the current knowledge of evading and immunosuppressive mechanisms elicited by Brucella species to persist stealthily in their hosts, such as those triggered by their LPS and cyclic β-1,2-d-glucan or involved in neutrophil and monocyte avoidance, antigen presentation impairment, the modulation of T cell responses and immunometabolism. Attractive strategies exploited by other successful chronic pathogenic bacteria, including Mycobacteria, Salmonella, and Chlamydia, will be also discussed, with a special emphasis on the mechanisms operating in brucellosis, such as granuloma formation, pyroptosis, and manipulation of type I and III IFNs, B cells, innate lymphoid cells, and host lipids. A better understanding of these stratagems is essential to fighting bacterial chronic infections and designing innovative treatments and vaccines.

Proteomics in Biomarker Discovery for Tuberculosis: Current Status and Future Perspectives

Tuberculosis (TB) continues to threaten many peoples' health worldwide, regardless of their country of residence or age. The current diagnosis of TB still uses mainly traditional, time-consuming, and/or culture-based techniques. Efforts have focused on discovering new biomarkers with higher efficiency and accuracy for TB diagnosis. Proteomics-the systematic study of protein diversity-is being applied to the discovery of novel protein biomarkers for different types of diseases. Mass spectrometry (MS) technology plays a revolutionary role in proteomics, and its applicability benefits from the development of other technologies, such as matrix-based and immune-based methods. MS and derivative strategies continuously contribute to disease-related discoveries, and some promising proteomic biomarkers for efficient TB diagnosis have been identified, but challenges still exist. For example, there are discrepancies in the biomarkers identified among different reports and the diagnostic accuracy of clinically applied proteomic biomarkers. The present review summarizes the current status and future perspectives of proteomics in the field of TB biomarker discovery and aims to elicit more promising findings for rapid and accurate TB diagnosis.

Immune Privilege Furnishes a Niche for Latent Infection

The microenvironment of the CNS (eye and brain) is fertile ground for infection if the barriers are breached. The result of pathogen invasion is often devastating destruction of tissues. In the eye, inflammation is broadly classified either as "infectious" (i.e. caused by infection) or "non-infectious". However, increasingly, forms of intraocular inflammation (IOI), which clinically appear to be "non-infectious" turn out to be initiated by infectious agents, suggesting that pathogens have been retained in latent or persistent form within ocular tissues and have reactivated to cause overt disease. A similar pathogenesis applies to latent infections in the brain. Not all CNS tissues provide an equally protective niche while different pathogens escape detection using different strategies. This review summarises how immune privilege (IP) in the CNS may be permissive for latent infection and allow the eye and the brain to act as a reservoir of pathogens which often remain undetected for the lifetime of the host but in states of immune deficiency may be activated to cause sight- and life-threatening inflammation.