Tuberculosis (TB) is an infectious disease. During TB, regulatory T cells (Treg) are related to poor prognosis. However, information about conventional and unconventional Treg (cTreg and uTreg, ...respectively) is limited. The tumour necrosis factor (TNF) and its receptors (TNFR1 and TNFR2) are necessary for mycobacterial infection, and TNFR2 signalling is required to maintain Treg.
A blood sample of drug-susceptible (DS-TB) and drug-resistant tuberculosis (DR-TB) patients was obtained before (basal) and after 2 and 6 months of anti-TB therapy. Expression of TNF, TNFR1, and TNFR2 (transmembrane form, tm) on cTreg, uTreg, activated CD4+ (actCD4+), and CD4+ CD25- (CD4+) T cell subpopulations were evaluated. The main objective was to identify immunological changes associated with sensitive/resistant Mtb strains and with the use of anti-TB therapy.
We found that after 6 months of anti-TB therapy, both DS- and DR-TB patients have decreased the frequency of cTreg tmTNF+, CD4+ tmTNFR1+ and CD4+ tmTNFR2+. Nevertheless, after 6 months of therapy, only DR-TB patients decreased the frequency of actCD4+ tmTNF+ and actCD4+ tmTNFR2+, exhibited a systemic inflammatory status (high levels of TNF, IFN-γ and IL-12), and their purified CD4+ T cells showed that TNF and TNFR2 are up-regulated at the transcriptional level. Moreover, DS- and DR-TB down-regulated TNFR1 and other proteins associated with Treg (FOXP3 and TGFβ1) in response to the anti-TB therapy.
These results partially explain the differences in the immune response of DS-TB vs DR-TB. The frequency of actCD4+ tmTNFR2+ cells and inflammatory status should be considered in the follow-up of therapy in DR-TB patients.
Tuberculosis continues to be a major public health problem. Although efforts to control the epidemic have reduced mortality and incidence, there are several predisposing factors that should be ...modified in order to reduce the burden of the disease. This review article will address some of the risk factors associated with tuberculosis infection and active tuberculosis, including diabetes, smoking, alcohol use, and the use of other drugs, all of which can also contribute to poor tuberculosis treatment results. Tuberculosis can also lead to complications in the course and management of other diseases, such as diabetes. It is therefore important to identify these comorbidities in tuberculosis patients in order to ensure adequate management of both conditions.
Neutrophil accumulation is associated with lung pathology during active tuberculosis (ATB). However, the molecular mechanism or mechanisms by which neutrophils accumulate in the lung and contribute ...to TB immunopathology are not fully delineated. Using the well-established mouse model of TB, our new data provide evidence that the alarmin S100A8/A9 mediates neutrophil accumulation during progression to chronic TB. Depletion of neutrophils or S100A8/A9 deficiency resulted in improved Mycobacterium tuberculosis (Mtb) control during chronic but not acute TB. Mechanistically, we demonstrate that, following Mtb infection, S100A8/A9 expression is required for upregulation of the integrin molecule CD11b specifically on neutrophils, mediating their accumulation during chronic TB disease. These findings are further substantiated by increased expression of S100A8 and S100A9 mRNA in whole blood in human TB progressors when compared with nonprogressors and rapidly decreased S100A8/A9 protein levels in the serum upon TB treatment. Furthermore, we demonstrate that S100A8/A9 serum levels along with chemokines are useful in distinguishing between ATB and asymptomatic Mtb-infected latent individuals. Thus, our results support targeting S100A8/A9 pathways as host-directed therapy for TB.
Highlights • The World Health Organization (WHO) 2016 guidelines for multidrug-resistant tuberculosis (MDR-TB) propose a regrouping of anti-TB drugs for the treatment of MDR-TB. • The classification ...of anti-TB drugs guides the clinician in designing an appropriate multidrug-/extensively drug-resistant TB regimen. • Discussion on possible future changes to the anti-TB drug groupings has started. • Based on recent evidence on some compounds, certain drugs are likely to increase or decrease in importance in the future. • If the efficacy and safety profile of linezolid, bedaquiline, and delamanid is confirmed, they might move up the anti-TB drug hierarchy.
•MDR-TB is difficult to manage; updated clinical guidance of new drug use is needed•No recent systematic review/meta-analysis on delamanid (DLM) is available•In observational studies including DLM ...(591 patients) the success rate was 80.9%•In experimental studies including DLM (391 patients) the success rate was 72.5%•Few adverse events attributable to DLM were reported
Multidrug-resistant tuberculosis (MDR-TB) is a life-threatening condition needing long poly-chemotherapy regimens. As no systematic reviews/meta-analysis is available to comprehensively evaluate the role of delamanid (DLM), we evaluated its effectiveness and safety.
We reviewed the relevant scientific literature published up to January 20, 2022. The pooled success treatment rate with 95% confidence intervals (CI) was assessed using a random-effect model. We assessed studies for quality and bias, and considered P<0.05 to be statistically significant.
After reviewing 626 records, we identified 25 studies that met the inclusion criteria, 22 observational and 3 experimental, with 1276 and 411 patients, respectively. In observational studies the overall pooled treatment success rate of DLM-containing regimens was 80.9% (95% CI 72.6-87.2) with no evidence of publication bias (Begg's test; P >0.05). The overall pooled treatment success rate in DLM and bedaquiline-containing regimens was 75.2% (95% CI 68.1-81.1) with no evidence of publication bias (Begg's test; P >0.05). In experimental studies the pooled treatment success rate of DLM-containing regimens was 72.5 (95% CI 44.2-89.8, P <0.001, I2: 95.1%) with no evidence of publication bias (Begg's test; P >0.05).
In MDR-TB patients receiving DLM, culture conversion and treatment success rates were high despite extensive resistance with limited adverse events.
Multidrug-resistant tuberculosis (MDR-TB) and extensively drug-resistant tuberculosis (XDR-TB) continue to challenge physicians and public health specialists. Global treatment outcomes continue to be ...unsatisfactory, positive outcomes being achieved in only 54% of patients. Overall outcomes are even worse in patients infected with highly resistant strains. Treating MDR-/XDR-TB is difficult because of frequent adverse events, the long duration of drug regimens, the high costs of second-line drugs, chronic post-infectious sequelae, and loss of organ function. Ongoing research efforts (studies and trials) have various aims: increasing the rates of treatment success; understanding the potentialities of new and repurposed drugs; shortening the treatment duration; and reducing the rates of adverse events. It is hoped that better access to rapid diagnostics, increased awareness, and treatments that are more effective will reduce the rate of complications and of lung function impairment. This article aims to discuss the management of severe tuberculosis (defined as that which is potentially life threatening, requiring higher levels of care) and its sequelae, from intensive care to the postoperative period, rehabilitation, and recovery. We also discuss the nonpharmacological interventions available to manage chronic sequelae and improve patient quality of life. Because the majority of MDR-/XDR-TB cases evolve to lung function impairment (typically obstructive but occasionally restrictive), impaired quality of life, and low performance status (as measured by walk tests or other metrics), other interventions (e.g., smoking cessation, pulmonary rehabilitation, vaccination/prevention of secondary bacterial infections/exacerbations, complemented by psychological and nutritional support) are required.
•The holistic management of tuberculosis (TB) patients can improve life-expectancy.•Pulmonary rehabilitation after TB treatment shows good effects for selected TB patients.•Disease-related ...malnutrition may lead to treatment failure in TB patients.•Nutritional status plays a key role in shaping immune responses.
The holistic management of tuberculosis (TB) patients can improve life expectancy and lost organ function.
Chronic sequelae are very common among patients who survive TB, which can lead to a further decline in lung function. There is still no guidance for ‘cured’ patients with impaired lung function who need pulmonary rehabilitation. Additional tests for evaluation should be given after the end of treatment, as recent studies have shown the good effect of pulmonary rehabilitation for TB patients.
Malnutrition is very common among TB patients and is related to malabsorption. The latter can cause lower drug exposure, which may result in treatment failure, increasing the risk of death, and can lead to acquired drug resistance. Malnutrition should be assessed according to the Global Leadership Initiative on Malnutrition (GLIM) criteria and the diagnosis should lead to an individualized treatment plan, including sufficient proteins and preferably in combination with adequate training.
Under normal circumstances, most immune cells use a glucose-based mechanism to generate energy. Therefore the patient’s nutritional status is a key factor in shaping immune responses. Disease-related malnutrition leads to proteolysis and lipolysis. In the end, the identification of individuals who will benefit from immune-modulatory strategies may lead to clinically relevant markers.
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.
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.
•M. tuberculosis-related inflammation outweighs the clinical outcomes of the disease•COX-2 inhibitors downregulate inflammation after Mtb infection•A whole-blood ex vivo model offers a straightforward time-efficient approach for evaluating drugs
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