Tuberculous pleural effusion-induced Arg-1+ macrophage polarization contributes to lung cancer progression via autophagy signaling.

BACKGROUND: The association between tuberculous fibrosis and lung cancer development has been reported by some epidemiological and experimental studies; however, its underlying mechanisms remain unclear, and the role of macrophage (MФ) polarization in cancer progression is unknown. The aim of the present study was to investigate the role of M2 Arg-1+ MФ in tuberculous pleurisy-assisted tumorigenicity in vitro and in vivo. METHODS: The interactions between tuberculous pleural effusion (TPE)-induced M2 Arg-1+ MФ and A549 lung cancer cells were evaluated. A murine model injected with cancer cells 2 weeks after Mycobacterium bovis bacillus Calmette-Guérin pleural infection was used to validate the involvement of tuberculous fibrosis to tumor invasion. RESULTS: Increased CXCL9 and CXCL10 levels of TPE induced M2 Arg-1+ MФ polarization of murine bone marrow-derived MФ. TPE-induced M2 Arg-1+ MФ polarization facilitated lung cancer proliferation via autophagy signaling and E-cadherin signaling in vitro. An inhibitor of arginase-1 targeting M2 Arg-1+ MФ both in vitro and in vivo significantly reduced tuberculous fibrosis-induced metastatic potential of lung cancer and decreased autophagy signaling and E-cadherin expression. CONCLUSION: Tuberculous pleural fibrosis induces M2 Arg-1+ polarization, and M2 Arg-1+ MФ contribute to lung cancer metastasis via autophagy and E-cadherin signaling. Therefore, M2 Arg-1+ tumor associated MФ may be a novel therapeutic target for tuberculous fibrosis-induced lung cancer progression.

Diagnostic accuracy and cellular origin of pleural fluid CXCR3 ligands for tuberculous pleural effusion.

BACKGROUND: Pleural biomarkers represent potential diagnostic tools for tuberculous pleural effusion (TPE) due to their advantages of low cost, short turnaround time, and less invasiveness. This study evaluated the diagnostic accuracy of two CXCR3 ligands, C-X-C motif chemokine ligand 9 (CXCL9) and CXCL11, for TPE. In addition, we investigated the cellular origins and biological roles of CXCL9 and CXCL11 in the development of TPE. METHODS: This double-blind study prospectively enrolled patients with undiagnosed pleural effusion from two centers (Hohhot and Changshu) in China. Pleural fluid on admission was obtained and levels of CXCL9 and CXCL11 were measured by an enzyme-linked immunosorbent assay (ELISA). The receiver operating characteristic (ROC) curve and the decision curve analysis (DCA) were used to evaluate their diagnostic accuracy and net benefit, respectively. THP-1 cell-derived macrophages were treated with Bacillus Calmette-Guérin (BCG), and quantitative real-time PCR (qRT-PCR) and ELISA were used to determine the mRNA and protein levels of CXCL9 and CXCL11. The chemoattractant activities of CXCL9 and CXCL11 for T helper (Th) cells were analyzed by a transwell assay. RESULTS: One hundred and fifty-three (20 TPEs and 133 non-TPEs) patients were enrolled in the Hohhot Center, and 58 (13 TPEs and 45 non-TPEs) were enrolled in the Changshu Center. In both centers, we observed increased CXCL9 and CXCL11 in TPE patients. The areas under the ROC curves (AUCs) of pleural CXCL9 and CXCL11 in the Hohhot Center were 0.70 (95 % CI: 0.55-0.85) and 0.68 (95 % CI: 0.52-0.84), respectively. In the Changshu Center, the AUCs of CXCL9 and CXCL11 were 0.96 (95 % CI: 0.92-1.00) and 0.97 (95 % CI: 0.94-1.00), respectively. The AUCs of CXCL9 and CXCL11 decreased with the advancement of age. The decision curves of CXCL9 and CXCL11 showed net benefits in both centers. CXCL9 and CXCL11 were upregulated in BCG-treated macrophages. Pleural fluid from TPE and conditioned medium from BCG-treated macrophages were chemotactic for Th cells. Anti-CXCL9 or CXCL11 neutralizing antibodies could partly block the chemotactic activity. CONCLUSIONS: Pleural CXCL9 and CXCL11 are potential diagnostic markers for TPE, but their diagnostic accuracy is compromised in elderly patients. CXCL9 and CXCL11 can promote the migration of peripheral Th cells, thus representing a therapeutic target for the treatment of TPE.

Vascular endothelial growth factor levels in tuberculosis: A systematic review and meta-analysis.

BACKGROUND: Changes in endothelial function are implicated in the spread of tuberculosis (TB). Studies suggest a role for the vascular endothelial growth factor (VEGF) in TB-related endothelial function changes. However, the findings of studies investigating the VGEF profile in TB are not consistent, and no formal systematic review and meta-analysis exists summarizing these studies. METHODS: We did a meta-analysis of studies assessing VEGF levels in patients with TB. A systematic search on June 25, 2021, was conducted for eligible studies that made VEGF measurements in an unstimulated sample, e.g., a blood fraction (plasma or serum), cerebrospinal fluid (CSF), pleural effusion (PE), or bronchoalveolar lavage fluid, and ascites or pericardial fluid for patients with TB and controls without TB. Also, studies that made simultaneous measurements of VEGF in blood and PE or CSF in the same patients with TB were included. Longitudinal studies that provided these data at baseline or compared pre-post anti-tuberculosis treatment (ATT) levels of VEGF were included. The primary outcome was the standardized mean difference (SMD) of VEGF levels between the comparison groups. RESULTS: 52 studies were included in the meta-analysis. There were 1787 patients with TB and 3352 control subjects of eight categories: 107 patients with transudative pleural effusion, 228 patients with congestive heart failure (CHF)/chronic renal failure (CRF), 261 patients with empyema and parapneumonic effusion (PPE), 241 patients with cirrhosis, 694 healthy controls (with latent TB infection or uninfected individuals), 20 patients with inactive tuberculous meningitis (TBM), 123 patients with non-TBM, and 1678 patients with malignancy. The main findings are as follows: (1) serum levels of VEGF are higher in patients with active TB compared with healthy controls without other respiratory diseases, including those with latent TB infection or uninfected individuals; (2) both serum and pleural levels of VEGF are increased in patients with TPE compared with patients with transudative, CHF/CRF, or cirrhotic pleural effusion; (3) ascitic/pericardial fluid, serum, and pleural levels of VEGF are decreased in patients with TB compared with patients with malignancy; (4) pleural levels of VEGF are lower in patients with TPE compared with those with empyema and PPE, whereas serum levels of VEGF are not different between these patients; (5) both CSF and serum levels of VEGF are increased in patients with active TBM compared with controls, including patients with inactive TBM or non-TBM subjects; (6) post-ATT levels of VEGF are increased compared with pre-ATT levels of VEGF; and (7) the mean age and male percentage of the TB group explained large and total amount of heterogeneity for the meta-analysis of blood and pleural VEGF levels compared with healthy controls and patients with PPE, respectively, whereas these moderators did not show any significant interaction with the effect size for other analyses. DISCUSSION: The important limitation of the study is that we could not address the high heterogeneity among studies. There might be unmeasured factors behind this heterogeneity that need to be explored in future research. Meta-analysis findings align with the hypothesis that TB may be associated with abnormal vascular function, and both local and systemic levels of VEGF can be used to trace this abnormality.

Nicotinamide phosphoribosyltransferase as a biomarker for the diagnosis of infectious pleural effusions.

Nicotinamide phosphoribosyltransferase (NAMPT) has been reported to be involved in infectious diseases, but it is unknown whether it plays a role in infectious pleural effusions (IPEs). We observed the levels of NAMPT in pleural effusions of different etiologies and investigated the clinical value of NAMPT in the differential diagnosis of infectious pleural effusions. A total of 111 patients with pleural effusion were enrolled in the study, including 25 parapneumonic effusions (PPEs) (17 uncomplicated PPEs, 3 complicated PPEs, and 5 empyemas), 30 tuberculous pleural effusions (TPEs), 36 malignant pleural effusions (MPEs), and 20 transudative effusions. Pleural fluid NAMPT levels were highest in the patients with empyemas [575.4 (457.7, 649.3) ng/ml], followed by those with complicated PPEs [113.5 (103.5, 155.29) ng/ml], uncomplicated PPEs [24.9 (20.2, 46.7) ng/ml] and TPEs [88 (19.4, 182.6) ng/ml], and lower in patients with MPEs [11.5 (6.5, 18.4) ng/ml] and transudative effusions [4.3 (2.6, 5.1) ng/ml]. Pleural fluid NAMPT levels were significantly higher in PPEs (P < 0.001) or TPEs (P < 0.001) than in MPEs. Moreover, Pleural fluid NAMPT levels were positively correlated with the neutrophil percentage and lactate dehydrogenase (LDH) levels and inversely correlated with glucose levels in both PPEs and TPEs, indicating that NAMPT was implicated in the neutrophil-associated inflammatory response in infectious pleural effusion. Further, multivariate logistic regression analysis showed pleural fluid NAMPT was a significant predictor distinguishing PPEs from MPEs [odds ratio (OR) 1.180, 95% confidence interval (CI) 1.052-1.324, P = 0.005]. Receiver-operating characteristic (ROC) analysis demonstrated that NAMPT was a promising diagnostic factor for the diagnosis of infectious effusions, with the areas under the curve for pleural fluid NAMPT distinguishing PPEs from MPEs, TPEs from MPEs, and IPEs (PPEs and TPEs) from NIPEs were 0.92, 0.85, and 0.88, respectively. In conclusion, pleural fluid NAMPT could be used as a biomarker for the diagnosis of infectious pleural effusions.

Potential diagnostic value of pleural fluid cytokines levels for tuberculous pleural effusion.

Patients with tuberculous pleural effusion (TPE) or malignant pleural effusions (MPE) frequently have similar pleural fluid profiles. New biomarkers for the differential diagnosis of TPE are required. We determined whether cytokine profiles in the PE of patients could aid the differential diagnosis of TPE. 30 patients with TPE, 30 patients with MPE, 14 patients with empyema (EMP) and 14 patients with parapneumonic effusion (PPE) were enrolled between Dec 2018 and 2019. The levels of interleukin (IL)-6, IL-18, IL-27, CXCL8, CCL-1 and IP-10 were determined in PE by ELISA along with measurements of adenosine deaminase (ADA). The best predictors of TPE were combined ADA.IL-27 [optimal cut-off value = 42.68 (103 U ng/l2), sensitivity 100%, specificity 98.28%], ADA [cut off value 27.5 (IU/l), sensitivity 90%, specificity 96.5%] and IL-27 [cut-off value = 2363 (pg/ml), sensitivity 96.7%, specificity 98.3%, p ≤ 0.0001]. A high level of IL-6 [cut-off value = 3260 (pg/ml), sensitivity 100%, specificity 67.2%], CXCL8 [cut-off value = 144.5 (pg/ml), sensitivity 93.3%, specificity 58.6%], CCL1 [cut-off value = 54 (pg/ml), sensitivity 100%, specificity 70.7%] and IP-10 [cut-off value = 891.9 (pg/ml), sensitivity 83.3%, specificity 48.3%] were also predictive of TPE. High ADA.IL-27, ADA and IL-27 levels differentiate between TPE and non-TPE with improved specificity and diagnostic accuracy and may be useful clinically.

Host-Derived Lipids from Tuberculous Pleurisy Impair Macrophage Microbicidal-Associated Metabolic Activity.

Mycobacterium tuberculosis (Mtb) regulates the macrophage metabolic state to thrive in the host, yet the responsible mechanisms remain elusive. Macrophage activation toward the microbicidal (M1) program depends on the HIF-1α-mediated metabolic shift from oxidative phosphorylation (OXPHOS) toward glycolysis. Here, we ask whether a tuberculosis (TB) microenvironment changes the M1 macrophage metabolic state. We expose M1 macrophages to the acellular fraction of tuberculous pleural effusions (TB-PEs) and find lower glycolytic activity, accompanied by elevated levels of OXPHOS and bacillary load, compared to controls. The eicosanoid fraction of TB-PE drives these metabolic alterations. HIF-1α stabilization reverts the effect of TB-PE by restoring M1 metabolism. Furthermore, Mtb-infected mice with stabilized HIF-1α display lower bacillary loads and a pronounced M1-like metabolic profile in alveolar macrophages (AMs). Collectively, we demonstrate that lipids from a TB-associated microenvironment alter the M1 macrophage metabolic reprogramming by hampering HIF-1α functions, thereby impairing control of Mtb infection.

Protein expression shift and potential diagnostic markers through proteomics profiling of tuberculous pleurisy biopsy tissues.

OBJECTIVES: Tuberculous pleurisy is a common type of tuberculosis (TB), but its diagnosis is challenging. This study aimed to profile the protein expression of this disease and identify new diagnostic makers. METHODS: Biopsy tissues from patients with tuberculous pleurisy and controls were taken through thoracoscopy, and proteins were extracted for Tandem Mass Tag Mass Spectrometry. Differential protein expression was performed between patients and controls, and the identified proteins were analyzed for pathway enrichment. Selected proteins were further validated in another set of samples using a more quantitative method. RESULTS: A total of 5101 proteins were detected and quantified in a discovery set of patients and controls. Overall protein expression was quite different between patients and controls. Most proteins were down-expressed, while a minority were overly expressed in the patient samples. At p value < 0.05 and absolute fold change >2, 295 proteins were found to be up-expressed and 608 down-expressed. The top enriched pathways included ECM-receptor interaction, complement and coagulation cascades and focal adhesion. All 19 selected candidates were validated in an independent set of patient and control samples. CONCLUSION: This unbiased proteomics approach not only provided unique insights into protein expression and pathways, but also discovered potential diagnostic markers for tuberculous pleurisy.

Diagnostic utility of pleural fluid T-SPOT and interferon-gamma for tuberculous pleurisy: A two-center prospective cohort study in China.

BACKGROUND: Early and accurate diagnosis of tuberculous pleurisy (TP) remains a challenge. The aim of the present study is to evaluate the performance of the pleural fluid (PF) T-SPOT and interferon-gamma (IFN-γ) for TP diagnosis in high tuberculosis (TB) burden settings. METHODS: In total, 214 and 217 subjects suspected of TP were prospectively enrolled in the Wuhan (training) cohort and Changchun (validation) cohort, respectively. All patients were examined with PF T-SPOT, IFN-γ, and other traditional tests simultaneously. RESULTS: The receiver-operating characteristic (ROC) curve analysis showed that the area under the curve (AUC), sensitivity, and specificity of TB-specific antigen (TBAg) spot-forming cells (SFC) (the larger of early secreted antigenic target 6 and culture filtrate protein 10 SFC in PF T-SPOT assay) for TP diagnosis were 0.972, 92.86%, and 92.16%, respectively, with a cutoff value of 35 in the Wuhan cohort. Meanwhile, when a threshold value of 95 ng/mL was set, the AUC, sensitivity, and specificity of IFN-γ to diagnose TP were 0.951, 86.61%, and 90.20%, respectively. Moreover, the diagnostic model based on the combination of TBAg SFC and IFN-γ showed an AUC of 0.983 for differentiating TP from non-TP, with 95.54% sensitivity and 95.10% specificity when a cutoff value of 0.32 was used in the Wuhan cohort. Excellent diagnostic accuracy was also observed in the Changchun cohort. When applying the cutoff value obtained from the Wuhan cohort, the AUC, sensitivity, and specificity of the diagnostic model were 0.995, 95.08%, and 97.89%, respectively. CONCLUSIONS: The performance of PF T-SPOT was comparable to IFN-γ in diagnosing TP. However, using the diagnostic model established by the combination of these two assays can achieve a more accurate diagnosis of TP.

Influence of age on the diagnostic accuracy of soluble biomarkers for tuberculous pleural effusion: a post hoc analysis.

BACKGROUND: Accurately diagnosing pleural effusion is a frequent and significant problem in clinical practice. Combining pleural biomarkers with patients' age may be a valuable method for diagnosing TPE. We sought to evaluate the influence of age on diagnostic values of pleural adenosine deaminase (ADA), interferon-gamma (IFN-γ), and interleukin 27 (IL-27) for tuberculous pleural effusion (TPE). METHODS: Two hundred seventy-four consecutive adult patients with pleural effusion were selected from Beijing and Wuhan between January 1, 2014 and June 30, 2015, and their pleural fluid concentrations of ADA, IFN-γ, and IL-27 were tested. Biomarker performance was analyzed by standard receiver operating characteristic (ROC) curves according to different ages. RESULTS: Data from the Beijing cohort showed that ADA, IFN-γ, and IL-27 could all accurately diagnose TPE in young patients (≤ 40 years of age). With a cutoff of 21.4 U/L, the area under the curve (AUC), sensitivity, specificity, positive predictive value (PPV), and negative predictive value (NPV) of ADA for diagnosing TPE were 1.000 (95% confidence interval: 0.884-1.000), 100.0, 100.0%, 100.0, and 100.0, respectively. In older patients (> 40 years of age), IL-27 and IFN-γ were excellent biomarkers for discriminating TPE versus non-TPE cases. With a cutoff of 591.4 ng/L, the AUC, sensitivity, specificity, PPV, and NPV of IL-27 for diagnosing TPE were 0.976 (95% confidence interval: 0.932-0.995), 96.3, 99.0%, 96.3, and 99.0, respectively. Similar diagnostic accuracy among the three pleural biomarkers was validated in the Wuhan cohort. CONCLUSIONS: Among young patients, ADA is reliable for diagnosing TPE. Conversely, in older patients, IL-27 and IFN-γ are excellent biomarkers to differentiate TPE versus non-TPE cases.

Th1/Th2 Imbalance and Elevated PD-L1 in Pleural Effusion Predict the Risk of Multi-Drug Resistant Tuberculous Pleuritis.

BACKGROUND: Patient immune status might be indicative of the variance in bacterial genetics in drug-resistant tuberculous pleuritis and could be used for predicting the risk of multi-drug resistant tuberculous pleuritis (MDR-TB). OBJECTIVE: To determine the significance of Th2/Th1 ratio and concentration of PD-L1 in the pleural effusions for prediction of MDR-TB. METHODS: We measured the ratio of Th2 to Th1 T cells from pleural effusions in 373 tuberculous pleuritis patients. We also measured the concentration of programmed death ligand-1 (PD-L1) in the pleural effusions of these patients. Afterwards, we determined the optimal cut-off value for predicting the occurrence of multi-drug resistant tuberculous based on the Youden index, diagnostic evaluation test, and receiver operation curve. Multiple logistic analysis was employed to identify the independent risk factors for MDR-TB occurrence. RESULTS: The area under the curve (AUC) of the Th2 to Th1 ratio was 0.66 and the concentration of PD-L1 was 0.71. Based on the combined detection of PD-L1 concentration in pleural effusion and the Th2 to Th1 ratio, our AUC was 0.81 and had a specificity of 0.92. Only a combined detection was able to identify patients developing multidrug-resistant tuberculosis. Multiple logistic analysis showed that a high concentration of PD-L1 and a high Th2 to Th1 ratio in pleural effusions were indicative of an immunocompromised status. Therefore, these measurements might be independent risk factors for the occurrence of multidrug-resistant tuberculous. CONCLUSION: Evaluation of immune status based on PD-L1 pleural concentration and Th2 to Th1 ratio might predict the risk of MDR-TB occurrence.

The comparison of pleural fluid TNF-α levels in tuberculous and nontuberculous pleural effusion.

BACKGROUND: Tuberculous pleural effusion is the manifestation of Mycobacterium tuberculosis infection in pleura. With existing means, it is difficult to establish the diagnosis of tuberculosis (TB) and non-TB pleural effusions; thus, establishing the diagnosis of TB pleural effusion and non-TB pleural effusion is still a clinical problem. Tumour necrosis factor alpha (TNFα) is a potent inflammatory cytokine that plays an important role in immunity to Mycobacterium tuberculosis infections, this level of cytokine increases in pleural effusion due to tuberculosis. OBJECTIVE: To compare the TNF-α level of pleural fluid in TB and non-TB pleural effusion. METHODS: The samples in this study that fulfilled the inclusion criteria were patients with non-TB pleural tuberculosis effusion in the inpatient ward in Pulmonology Unit Dr. Soetomo General Hospital Surabaya, male and female, aged between 15 and 60 years. The data is divided into two: primary data and secondary data of patients who fulfilled inclusion and exclusion criteria. The data with normal distribution was analyzed using independent t2 test and if the data distribution is abnormal, it was analyzed using Fisher's exact test. RESULTS: There were 22 subjects divided into 2 groups that were 11 patients with TB pleural effusion and 11 patients with non-TB pleural effusion. The TNF-α level of pleural fluid in TB pleural effusion was 25.43±13.55pg/mL. The TNF-α level of pleural fluid in non-TB was 5.98±1.89pg/mL. The serum TNF-α level in TB pleural effusion was 83.22±88.15pg/mL. The serum TNF-α level in non-TB was 68.54±57.88pg/mL. There was higher level of TNF-α pleural fluid in TB pleural effusion than in non-TB pleural effusion (25.43±13.55pg/mL vs 5.98±1.89pg/mL, p value <0.05). The serum TNF-α level in patients with TB pleural effusion was higher than TNF-α serum level of non-TB pleural effusion. There was no significant difference between TNF-α level of pleural fluid and serum TNF-α levels in the TB pleural effusion group (p value >0.05). CONCLUSION: The TNF-α level of pleural fluid in TB pleural effusion was higher than non-TB pleural effusions and there was no significant difference between serum TNF-α levels in the TB pleural effusion group and in the non-TB pleural effusion group.

Serial anti-tuberculous immune responses during the follow-up of patients with tuberculous pleurisy.

Little is known about the decay kinetics of interferon (IFN)-γ response and its influencing factors in tuberculous pleurisy. We enrolled thirty-two patients with tuberculous pleurisy prospectively and followed up at month 0, 6, and 9, at which time peripheral venous blood was drawn for interferon gamma release assay (IGRA) by means of QuantiFERON-TB Gold In-Tube (QFT-GIT). Demographic and clinical data were captured. To identify significant predictive factors influencing the IFN-γ response, multiple linear regression analyses were performed. Percentage of CD4+, CD8+, Vγ2Vδ2 T cells and Treg cells were measured by flow cytometry. The percentage of QFT-GIT-positive patients at baseline, month 6 and month 9 were 96.9% (30/32), 90.6% (29/32) and 84.4% (27/32), respectively. Quantitative IFN-γ response at baseline were significantly correlated with symptom duration (P = .003, R = 0.261) and age (P = .041, R = 0.132). Besides, the decreases of the IFN-γ response at month 6 and month 9 were positively correlated with the IFN-γ level at baseline. The dynamic tendency of the percentages of Treg cells was similar to the IFN-γ responses at each time-point. Quantitative IFN-γ response could be influenced by host immune status, instead of disease burden and anti-tuberculosis treatment. IGRA is probably not a useful biomarker of treatment efficacy in tuberculous pleurisy.

PD-1-expressing MAIT cells from patients with tuberculosis exhibit elevated production of CXCL13.

To understand functional role of PD-1-expressing MAIT cells during tuberculosis infection in humans, sorted PD-1+ and PD-1- MAIT cells from pleural effusions of patients with pleural tuberculosis were subjected to transcriptome sequencing. PD-1-expressing MAIT cells were analysed by flow cytometry and their phenotypic and functional features were investigated. Transcriptome sequencing identified 144 genes that were differentially expressed between PD-1+ and PD-1- MAIT cells from tuberculous pleural effusions and CXCL13 was the gene with highest fold difference. The level of PD-1-expressing MAIT cells was associated with extent of TB infection in humans. PD-1-expressing MAIT cells had increased production of CXCL13 and IL-21 as determined by flow cytometry. PD-1high CXCR5- MAIT cells were significantly expanded in pleural effusions from patients with pleural tuberculosis as compared with those from peripheral blood of both patients with tuberculosis and healthy controls. Although PD-1high CXCR5- MAIT cells from tuberculous pleural effusions had reduced IFN-γ level and increased expression of Tim-3 and GITR, they showed activated phenotype and had higher glucose uptake and lipid content. It is concluded that PD-1-expressing MAIT cells had reduced IFN-γ level but increased production of both CXCL13 and IL-21.

The role of genexpert in the diagnosis of tubercular pleural effusion in India.

INTRODUCTION: Tubercular pleural effusion is the second most common extrapulmonary form of tuberculosis in India. Developing nations like India face several health challenges and with limited resources, appropriate planning and channelization of the same is the need of the hour. MATERIAL AND METHODS: The objective of the study was to determine the role of cartridge-based nucleic acid amplification test (CBNAAT) in the diagnosis of tubercular pleural effusion (TPE) and also to study if any association exists between CBNAAT and pleural fluid adenosine deaminase (ADA) and lymphocyte counts. Clinically suspected TPE, lymphocyte predominant (≥ 70%) exudates (according to the Lights criteria) with ADA ≥ 40 U/L and microbiologically confirmed pulmonary tuberculosis patients with aco-existent pleural effusion were included. Pleural fluid CBNAAT was performed on all the samples. RESULTS: Out of atotal of 75 patients, 57 were males and 18 were females. Alymphocyte predominance of ≥ 70% was seen in 73 subjects (97%). Mean ADA was 61.7 U/L ± 16.2 (SD). Pleural fluid CBNAAT was positive for Mycobacterium tuberculosis (MTB) in 24 patients (32%). Out of these patients, rifampicin resistance was detected in 2 individuals (8.3%). Sputum smear for acid fast bacilli (AFB) was positive in 3 (4%) patients, whereas in sputum CBNAAT MTB was detected in 8 (10.6%) persons. Association between pleural fluid ADA, lymphocyte count and CBNAAT positivity was evaluated by Student T-test. There was asignificant association between higher ADA levels and CBNAAT (p value = 0.001). CONCLUSIONS: Pleural fluid CBNAAT, owing to its low sensitivity, should not be included in the diagnostic protocol of TPE in high prevalence areas. Ahigh ADA ≥ 40 U/L in combination with Light's criteria to define exudates, with lymphocyte predominance is sufficient evidence to diagnose TPE and initiate anti-tubercular therapy, thereby deferring the need to perform an invasive pleural biopsy.

High expression of BTLA and B7-H4 on the surface of myeloid dendritic cells has a negative regulatory effect on their anti-tuberculosis immunity activity in pleural tuberculosis patients.

To investigate the effects of the surface markers B- and T-lymphocyte attenuator (BTLA) and B7 homologous body 4 (B7-H4) on expression of CD83, and Human Leukocyte Antigen-DR isotype (HLA-DR) that can activate dendritic cells (DCs). Flow cytometry was used to detect the co-expression of BTLA and B7-H4 on myeloid DCs (mDCs) in peripheral blood (PB) and pleural effusions (PE) in 15 volunteers and 20 tuberculous pleurisy (TP) patients. Co-expression of BTLA and B7-H4 (double positive (DP)) mDCs in PB and PE of TP patients were enhanced. The proportion of DP mDC in PB decreased markedly after 2 weeks treatment, but was still greater than in controls. Expression of CD83 and HLA-DR on DP mDCs was higher than on BTLA and B7-H4 double negative (DN) expressing mDCs in PB of different TP groups. Expression of CD83 on DP mDCs in PB and PE of TP patients was greater than that of controls. Expression of HLA-DR on DP mDCs in TP patient PB was lower than in TP PE and controls. In pleural tuberculosis (TB) patients, high expression of BTLA and B7-H4 promoted a high level of CD83 and HLA-DR, which had a negative regulatory effect on mDCs on anti-TB immunity.

Predominance of Th1 Immune Response in Pleural Effusion of Patients with Tuberculosis among Other Exudative Etiologies.

Pleural tuberculosis (PlTB), a common form of extrapulmonary TB, remains a challenge in the diagnosis among many causes of pleural effusion. We recently reported that the combinatorial analysis of interferon gamma (IFN-γ), IFN-γ-inducible protein 10 (IP-10), and adenosine deaminase (ADA) from the pleural microenvironment was useful to distinguish pleural effusion caused by TB (microbiologically confirmed or not) among other etiologies. In this cross-sectional cohort study, a set of inflammatory mediators was quantified in blood and pleural fluid (PF) from exudative pleural effusion cases, including PlTB (n = 27) and non-PlTB (nTB) (n = 25) patients. The levels of interleukin-2 (IL-2), IL-4, IL-6, IL-10, IL-17A, IFN-γ, tumor necrosis factor (TNF), IP-10, transforming growth factor ß1 (TGF-ß), and ADA were determined using cytometric bead assay, enzyme-linked immunosorbent assay (ELISA), or biochemical tests. IFN-γ, IP-10, TNF, TGF-ß, and ADA quantified in PF showed significantly higher concentrations in PlTB patients than in nTB patients. When blood and PF were compared, significantly higher concentrations of IL-6 and IL-10 in PF were identified in both groups. TGF-ß, solely, showed significantly increased levels in PF and blood from PlTB patients when both clinical specimens were compared to those from nTB patients. Principal-component analysis (PCA) revealed a T helper type 1 (Th1) pattern attributed mainly to higher levels of IP-10, IFN-γ, TGF-ß, and TNF in the pleural cavity, which was distinct between PlTB and nTB. In conclusion, our findings showed a predominantly cellular immune response in PF from TB cases, rather than other causes of exudative effusion commonly considered in the differential diagnosis of PlTB.

Diagnostic role of interleukin -33 in the differentiation of pleural effusions especially tuberculous and malignant effusions.

BACKGROUND: Tuberculous pleurisy and malignancy are two of the most common causes of pleural effusion. IL-33 is expressed in the epithelial lining and endothelial cells and is released after cell damage; it is proposed to have an essential role in sensing damage in various infectious and inflammatory diseases. This work aimed to determine the diagnostic role of IL-33 in pleural effusions. METHODS: One hundred seventeen patients with pleural effusions of different etiologies had a quantitative measurement of IL-33 in their pleural effusion and serum samples by ELISA technique. RESULTS: The concentrations of IL-33 (mean ± SD) in tuberculous pleural effusion (TPE) group (22.5 ± 0.90 ng/l) were significantly higher than that of malignant pleural effusion (MPE) group (14.6 ± 2.35 ng/l; P <  0.001). There is no significant difference between the serum levels of IL-33 in (TPE) group and (MPE) group (P >  0.05). The concentrations of IL-33 in the pleural effusions were significantly correlated to that of the serum concentrations in each group (TPE: r = 0.848, P = < 0.001; MPE: r = 0.881, < 0.001) and pleural ADA in patients with tuberculous pleural effusions, (r = 0.38, P <  0.001). The cut-off value of pleural IL33 for (TPE) was 19.16 ng/l, with a sensitivity of 91.7%, a specificity of 96.4%. The cutoff point of a pleural/ serum IL-33 ratio for the diagnosis of TPE was > 1.4 with a sensitivity of 91.7% and specificity of 100% while for the determination of (MPE) was < 0.9 with a sensitivity of 83.3% and specificity of 96.4%. CONCLUSION: IL-33 level may serve as a novel biomarker to differentiate pleural effusions, especially tuberculous from malignant effusions.

Down regulation of RANTES in pleural site is associated with inhibition of antigen specific response in tuberculosis.

Tuberculosis is the most common infectious reason for death and a major cause of pleural effusion globally. To understand the role of chemokines in trafficking of cells during TB pleurisy, we studied the responses to MTB, Ag85A in cells from pleural fluids and peripheral blood. Patients with TB pleural effusions, malignant effusions and asymptomatic healthy controls were enrolled. High expression (p < 0.05) of IP-10, MCP-1, MIG, IL-8, IFN-γ and IL-23 were observed in pleural fluids of TB patients compared to their plasma where expression of RANTES was significantly higher (p < 0.05). On specific stimulation of PFMCs with Ag85A, expression of RANTES was significantly lower in TB compared to NTB patients. We also observed increased expression of T regs and PD1 on CD8+T cells in PFMC of TB patients. Though some of the inflammatory chemokine/cytokines were up-regulated in pleura of TB patients, antigenic stimulation failed to induce them indicating poor antigenic responses at the site. Low expression of RANTES might be a reason for decreased trafficking of cells to the site and dissemination of infection into pleural site. The pattern of RANTES expression in pleural fluid vs serum is interesting. The observations necessitate further studies to investigate the levels of RANTES for its potential biological relevance in TB immunity and its use as a biomarker for diagnosis of pleural TB.

Potential biomarkers for antidiastole of tuberculous and malignant pleural effusion by proteome analysis.

AIM: To investigate novel potential biomarkers for antidiastole of tuberculous pleural effusion (TPE) from malignant pleural effusion (MPE). MATERIALS & METHODS: iTRAQTM-coupled LC-MS/MS were applied to analyze the proteome of TPE and MPE samples. The candidate proteins were verified by enzyme-linked immunosorbent assay. RESULTS: A total of 432 differential proteins were identified. Enzyme-linked immunosorbent assay revealed significantly higher levels of fibronectin (FN) and cathepsin G (CTSG) in MPE than in TPE, but lower levels of leukotriene-A4 hydrolase (LTA4H). The receiver operator characteristic values were 0.285 for FN, 0.64 for LTA4H, 0.337 for CTSG and 0.793 for a combination of these candidate markers. CONCLUSION: FN, LTA4H and CTSG were identified as potential biomarkers to differentiate TPE from MPE and their combination exhibited higher diagnostic capacity.

Tuberculous Pleural Effusion: Clinical Characteristics of 320 Patients. / Derrame pleural tuberculoso: características clínicas de 320 pacientes.

OBJECTIVES: To analyze the clinical and radiological characteristics and features of pleural fluid (PF) in patients with tuberculous pleural effusion (TPE). METHODS: Retrospective analysis of TPEs treated in our clinic over the last 23years. RESULTS: We included 320 patients with TPE (70% men; median age 33years). Mycobacterium tuberculosis was identified in the sputum or PF of 36% of the patients by microscopic examination, solid and liquid media cultures, or nucleic acid amplification tests. The greatest percentage of positive microbiological findings were associated with human immunodeficiency virus (HIV) co-infection (OR: 3.27), and with the presence in PF of proteins <4g/dL (OR: 3.53), neutrophils >60% (OR: 3.23), and glucose <40mg/dL (OR: 3.17). Pleural adenosine deaminase <35U/L was associated with TPEs that occupied less than half of the hemithorax (OR: 6.36) and with PF lactate dehydrogenase levels <500U/L (OR: 8.09). Radiological pulmonary opacities (30%) were more common in TPE occupying less than half of the hemithorax (OR: 2.73), in bilateral TPE (OR: 4.48), and in older patients (OR: 1.02). Factors predicting mortality were: HIV co-infection (OR: 24), proteins in PF <5g/dL (OR: 10), and greater age (OR: 1.05). CONCLUSIONS: Patients with TPE and HIV co-infection and those with lower concentrations of proteins in PF had higher rates of positive microbiological results and death. Moreover, older patients had more pulmonary opacities and a higher incidence of death.