Heightened systemic levels of anti-inflammatory cytokines in pulmonary tuberculosis and alterations following anti-tuberculosis treatment

Impaired control of Mycobacterium tuberculosis infection in mast cell-deficient KitW-sh/W-sh mice

Tuberculosis (TB) is a global health problem with diverse clinical manifestations. Different cells of the immune response participate in containing the infection, mainly through the development of granulomas. Mast cells (MCs) are hematopoietic cells that participate in the immune response to different pathogens, and in vitro evidence indicates that they can be activated by Mycobacterium tuberculosis (Mtb). The aim of this study was to evaluate the role of MCs in a murine TB model. We observed that KitW-sh/W-sh mast cell-deficient mice showed increased bacterial load in the lungs and the spleen compared to wild-type C57BL/6 mice. Furthermore, MC-deficient mice showed fewer pulmonary granulomas but an early higher inflammatory infiltrate. Interestingly, serum cytokine levels were altered in MC-deficient mice, which showed increased levels of IL-4, IL-5, and IL-22 during the early phase of the infection but increased levels of IFN-γ, IL-9, IL-10, and IL-21 during the late phase of the infection. These results show that mast cells play an important role during Mtb infection by modulating the immune response to the bacteria.

Challenges of Multidrug-Resistant Tuberculosis Meningitis: Current Treatments and the Role of Glutathione as an Adjunct Therapy

Multidrug-resistant tuberculosis (MDR-TB) poses a significant global health threat, especially when it involves the central nervous system (CNS). Tuberculous meningitis (TBM), a severe manifestation of TB, is linked to high mortality rates and long-term neurological complications, further exacerbated by drug resistance and immune evasion mechanisms employed by Mycobacterium tuberculosis (Mtb). Although pulmonary TB remains the primary focus of research, MDR-TBM introduces unique challenges in diagnosis, treatment, and patient outcomes. The effectiveness of current treatments is frequently compromised by poor CNS penetration of anti-TB drugs and the necessity for prolonged therapy, which often involves considerable toxicity. This review explores the potential of cytokine-based adjunct immunotherapies for MDR-TBM, addressing the challenges of balancing pro-inflammatory and anti-inflammatory signals within the CNS. A central focus is the prospective role of glutathione, not only in reducing oxidative stress but also in enhancing host immune defenses against Mtb's immune evasion strategies. Furthermore, the development of vaccines aimed at upregulating glutathione synthesis in macrophages represents a promising strategy to bolster the immune response and improve treatment outcomes. By integrating glutathione and innovative vaccine approaches into MDR-TBM management, this review proposes a comprehensive strategy that targets Mtb directly while supporting immune modulation, with the potential to enhance patient outcomes and reduce treatment related adverse effects. We underscore the urgent need for further research into adjunctive therapies and immunomodulatory strategies to more effectively combat MDR-TBM.

Association Between Indices of Peripheral Blood Inflammation and Cavitary Pulmonary Tuberculosis

Objective

To explore inflammation markers of C-reactive protein (CRP), neutrophil-to-lymphocyte ratio (NLR), monocyte-to-lymphocyte ratio (MLR), platelet-to-lymphocyte ratio (PLR), systemic immune-inflammatory index (SII), and systemic inflammatory response index (SIRI) in the differential diagnosis of cavitary pulmonary tuberculosis (PTB) from non-cavitary PTB.

Methods

This retrospective study included 1233 patients with PTB, 518 patients were diagnosed with cavitary PTB as case group, while 715 patients which diagnosed with non-cavitary PTB were selected as control group. The clinical data of patients was collected and the levels of inflammation indices were measured. Receiver operating characteristic (ROC) curve analysis was used to assess the diagnosis and analysis of selected indices. Logistic regression analysis was performed to evaluate the factors associated with cavitary PTB.

Results

The CRP, NLR, MLR, PLR, SII, and SIRI in the case group were significantly higher than those in the controls (all p<0.001). When cavitary PTB was taken as the endpoint, the optimal diagnostic thresholds of CRP was 35.365 (area under the ROC curve (AUC)=0.601), NLR was 5.740 (AUC=0.595), MLR was 0.525 (AUC=0.577), PLR was 198.255 (AUC=0.602), SII was 1252.045 (AUC=0.628), and SIRI was 2.095 (AUC=0.605), respectively. Logistic regression analysis showed that gender, CRP, PLR, and SIRI were the independent risk factors for cavitary PTB. The sensitivity of the combination of the three indices (CRP+PLR, CRP+SIRI, PLR+SIRI, and CRP+PLR+SIRI) were higher than those of the CRP, PLR, and SIRI.

Conclusion

CRP, PLR, and SIRI levels were associated with an increased likelihood of cavitary PTB. The combined detection of CRP, PLR, and SIRI is promising as a screening marker and may be useful for ruling out PTB with cavitary.

Whole-blood culture-derived cytokine combinations for the diagnosis of tuberculosis

Introduction

The diagnosis of tuberculosis (TB) disease and TB infection (TBI) remains a challenge, and there is a need for non-invasive and blood-based methods to differentiate TB from conditions mimicking TB (CMTB), TBI, and healthy controls (HC). We aimed to determine whether combination of cytokines and established biomarkers could discriminate between 1) TB and CMTB 2) TB and TBI 3) TBI and HC.

Methods

We used hemoglobin, total white blood cell count, neutrophils, monocytes, C-reactive protein, and ten Meso Scale Discovery analyzed cytokines (interleukin (IL)-1β, IL-2, IL-4, IL-6, IL-8, IL-10, IL-12p70, IL-13, interferon (IFN)-ɣ, and tumor necrosis factor (TNF)-α) in TruCulture whole blood tubes stimulated by lipopolysaccharides (LPS), zymosan (ZYM), anti-CD3/28 (CD3), and unstimulated (Null) to develop three index tests able to differentiate TB from CMTB and TBI, and TBI from HC.

Results

In 52 persons with CMTB (n=9), TB (n=23), TBI (n=10), and HC (n=10), a combination of cytokines (LPS-IFN-ɣ, ZYM-IFN-ɣ, ZYM-TNF-α, ZYM-IL-1β, LPS-IL-4, and ZYM-IL-6) and neutrophil count could differentiate TB from CMTB with a sensitivity of 52.2% (95% CI: 30.9%-73.4%) and a specificity of 100 % (66.4%-100%). Null- IFN-ɣ, Null-IL-8, CD3-IL-6, CD3-IL-8, CD3-IL-13, and ZYM IL-1b discriminated TB from TBI with a sensitivity of 73.9% (56.5% - 91.3%) and a specificity of 100% (69.2-100). Cytokines and established biomarkers failed to differentiate TBI from HC with ≥ 98% specificity.

Discussion

Selected cytokines may serve as blood-based add-on tests to detect TB in a low-endemic setting, although these results need to be validated.

Distinct TB-antigen stimulated cytokine profiles as predictive biomarkers for unfavorable treatment outcomes in pulmonary tuberculosis

Introduction

The assessment of tuberculosis (TB) treatment outcomes predominantly relies on sputum culture conversion status. To enhance treatment management, it is crucial to identify non-sputum-based biomarkers that can predict unfavorable outcomes. Cytokines are widely studied as diagnostic biomarkers for active TB. However, their potential as indicators for unfavorable treatment outcomes remains uncertain.

Methodology

This study was conducted within a well-characterized cohort comprising newly diagnosed patients with drug-sensitive pulmonary TB, confirmed through sputum smear and culture positivity. Our objective was to elucidate the TB antigen-stimulated cytokine profile at pre-treatment and at 2 months into anti-TB treatment (ATT) in patients with unfavorable treatment outcomes (cases, n = 27) in comparison to recurrence-free, microbiologically cured controls (n = 31). Whole blood was stimulated with TB antigens using the QuantiFERON In-tube gold method, and plasma supernatants were subjected to a panel of 14 cytokine measurements.

Results

In our study, pre-treatment analysis revealed that eight cytokines (IL-2, IFN-γ, TNF-α, IL-6, IL-10, IL-17A, IL-18, and GM-CSF) were significantly elevated at baseline in cases compared to cured controls, both in unstimulated conditions and following TB antigen (CFP10, ESAT6, and TB7.7) stimulation. A similar pattern was observed at the 2-month mark of ATT, with eight cytokines (IL-2, IL-10, IL-13, IFN-γ, IL-6, IL-12p70, IL-17A, and TNF-α) showing significant differences between the groups. Importantly, no variations were detected following mitogen stimulation, underscoring that these distinctive immune responses are primarily driven by TB-specific antigens.

Conclusion

Our findings indicate that individuals with unfavorable TB treatment outcomes display a characteristic cytokine profile distinct from TB-cured patients, even before commencing ATT. Therefore, the levels of specific cytokine pre-treatment and at the 2-month point in the course of treatment may serve as predictive immune markers for identifying individuals at risk of unfavorable TB treatment outcomes, with these responses being predominantly influenced by TB-specific antigens.

Inflammatory immune profiles associated with disease severity in pulmonary tuberculosis patients with moderate to severe clinical TB or anemia

Background

Immune control of Mycobacterium tuberculosis (Mtb) infection is largely influenced by the extensive disease heterogeneity that is typical for tuberculosis (TB). In this study, the peripheral inflammatory immune profile of different sub-groups of pulmonary TB patients was explored based on clinical disease severity, anemia of chronic disease, or the radiological extent of lung disease.

Methods

Plasma samples were obtained from n=107 patients with active pulmonary TB at the time of diagnosis and after start of standard chemotherapy. A composite clinical TB symptoms score, blood hemoglobin status and chest X-ray imaging were used to sub-group TB patients into 1.) mild and moderate-severe clinical TB, 2.) anemic and non-anemic TB, or 3.) limited and extensive lung involvement. Plasma levels of biomarkers associated with inflammation pathways were assessed using a Bio-Plex Magpix 37-multiplex assay. In parallel, Th1/Th2 cytokines were quantified with a 27-multiplex in matched plasma and cell culture supernatants from whole blood stimulated with M. tuberculosis-antigens using the QuantiFERON-TB Gold assay.

Results

Clinical TB disease severity correlated with low blood hemoglobin levels and anemia but not with radiological findings in this study cohort. Multiplex protein analyses revealed that distinct clusters of inflammation markers and cytokines separated the different TB disease sub-groups with variable efficacy. Several top-ranked markers overlapped, while other markers were unique with regards to their importance to differentiate the TB disease severity groups. A distinct immune response profile defined by elevated levels of BAFF, LIGHT, sTNF-R1 and 2, IP-10, osteopontin, chitinase-3-like protein 1, and IFNα2 and IL-8, were most effective in separating TB patients with different clinical disease severity and were also promising candidates for treatment monitoring. TB patients with mild disease displayed immune polarization towards mixed Th1/Th2 responses, while pro-inflammatory and B cell stimulating cytokines as well as immunomodulatory mediators predominated in moderate-severe TB disease and anemia of TB.

Conclusions

Our data demonstrated that clinical disease severity in TB is associated with anemia and distinct inflammatory immune profiles. These results contribute to the understanding of immunopathology in pulmonary TB and define top-ranked inflammatory mediators as biomarkers of disease severity and treatment prognosis.

Serum levels of IL-6/IL-10/GLDH may be early recognition markers of anti-tuberculosis drugs (ATB) -induced liver injury

To explore the potential value of serum glutamate dehydrogenase (GLDH) combined with inflammatory cytokines as diagnostic biomarkers for anti-tuberculosis drug -induced liver injury (ATB-DILI). We collected the residual serum from the patients who met the criteria after liver function tests. We have examined these parameters including GLDH which were determined by enzyme-linked immunosorbent assay and cytokines which were determined by cytokine combination detection kit. Multivariate logistics stepwise forward regression was applied to establish regression models. A total of 138 tuberculosis patients were included in the diagnostic markers study of ATB-DILI, including normal liver function group (n = 108) and ATB-DILI group(n = 30). Serum GLDH, IL-6 and IL-10 levels were significantly increased in the ATB-DILI group. Receiver operating characteristic curve (ROC) curve showed that the area under curve (AUC) of serum GLDH, IL-6 and IL-10 for the diagnosis of ATB-DILI were 0.870, 0.714 and 0.811, respectively. In logistic regression modeling, the AUC of GLDH combined with IL-10 as an ATB-DILI marker is 0.912. Serum IL-6、IL-10 and GLDH levels began to rise preceded the increase in ALT by 7 days, with significant differences in IL-6 compared with 7 days. Serum GLDH, IL-6 and IL-10 levels were correlated with the severity of liver injury. In conclusion, we found that GLDH, IL-6 and IL-10 alone as diagnostic markers of ATB-DILI had good diagnostic efficacy. Logistic regression model established by GLDH and IL-10 had better diagnostic efficacy and IL-6 may be an early predictor of liver injury in the setting of ATB poisoning.

Interleukin-4 expression is increased in patients with tuberculosis: A systematic review and meta-analysis

BACKGROUND

Interleukin-4 (IL-4) is an important cytokine in the Th2 differentiation of CD4+ T cells, which modulates immune responses and participates in host defense against Mycobacterium tuberculosis. The present study aimed to evaluate the significance of IL-4 concentration in patients with tuberculosis. Data from this study will be helpful in understanding the immunological mechanisms of tuberculosis and in clinical practice.

METHOD

A data search was conducted from January 1995 to October 2022 in electronic bibliographic databases such as China National Knowledge Infrastructure, Wan Fang, Embase, Web of Science, and PubMed. The Newcastle-Ottawa Scale was used to assess the quality of the included studies. Heterogeneity between the studies was assessed using I2 statistics. Publication bias was determined by funnel plot, and Egger's test was used to confirm the presence of publication bias. All qualified studies and statistical analyses were performed using Stata 11.0.

RESULTS

Fifty-one eligible studies comprising 4317 subjects were included in the meta-analysis. The results depicted a considerably increased level of serum IL-4 in patients with tuberculosis than in the controls (standard mean difference [SMD] = 0.630, [95% confidence interval (CI), 0.162-1.092]). However, there was no significant difference in plasma IL-4 levels between patients with TB and controls (SMD = 0.290, [95% CI, -0.430 to 1.010]). In addition, the infection status, TB focus location, drug resistance, race, research design type, and detection method divided the subjects into different subgroups for the meta-analysis. The results of the comparison of healthy controls and TB subjects showed that in the Asian population, the serum IL-4 level in patients with TB was higher than that in controls (SMD = 0.887, [95% CI, 0.202 to -1.573]) and patients with active TB as well as people with pulmonary TB showed increased serum IL-4 levels compared to controls (SMD = 0.689, [95% CI, 0.152-1.226]). In the case of the control group with latent TB, the active TB group had higher serum IL-4 levels than the control group (SMD = 0.920, [95% CI, 0.387-1.452]).

CONCLUSION

The present meta-analysis showed that serum IL-4 varied in healthy individuals and patients with TB. Patients with active TB may also exhibit higher IL-4 concentrations.

Plasma Vitamin D levels in correlation with circulatory proteins could be a potential biomarker tool for pulmonary tuberculosis and treatment monitoring

BACKGROUND

Tuberculosis (TB), a life-threatening immune challenging disease to the global human community has to be diagnosed earlier and eliminated in the upcoming era. Vitamin D, a fat-soluble micronutrient, mainly from epidermal cells of the skin and a few dietary sources, is associated with the immune system in various disease management. Therefore, a better understanding of vitamin D metabolism and immune function in tuberculosis should be studied for the consideration of biomarkers.

METHODS

The study consist of Pulmonary Tuberculosis (PTB) patients (n = 32) at two-time points: Baseline (PTB BL) and after 6 months of anti-TB treatment (ATT) (PTB PT), latently Mtb infected (IFNγ + ) group (n = 32) and a non-LTB healthy control (IFNγ-) group (n = 32). Vitamin D levels were measured using High-performance liquid chromatography (HPLC). The cytokine data from the same participants assayed by ELISA from our earlier investigations were used to correlate it with serum Vitamin D levels.

RESULTS

The assayed serum Vitamin D levels between the groups showed significantly lowered levels in PTB BL when compared with IFNγ + and IFNγ- groups. And, the Vitamin D levels in the PTB group after ATT were significantly lower than the baseline levels. The Vitamin D data were compared with pro- and anti-inflammatory cytokines and adipokines levels by performing a principal component regression analysis. Based on the PC scores, the study group showed distinct clusters for the TB group and control group. And, the correlation analysis between the study group and immunological indices showed significant correlations. Vitamin D significantly correlated with IFNγ, TNFα, IL17A, IL-4 and Resistin in the TB group, whereas IL-6 and G-CSF in the control group.

CONCLUSION

The baseline measurement of Vitamin D levels was significantly decreased in the PTB group when compared with IFNγ + and IFNγ- groups showing the importance of Vitamin D as a preventive factor against the TB disease progression. The six-month post-treatment of TB showed a further decrease in Vitamin D levels in PTB. The significantly correlated immunological indices with Vitamin D levels are the biomarker profile that could predict TB.

Low body mass index is associated with diminished plasma cytokines and chemokines in both active and latent tuberculosis

Introduction

Low body mass index (BMI) is a major risk factor for tuberculosis (PTB). Low BMI can impair the immune system and thus might affect TB incidence.

Methods

We examined the plasma levels of Type 1, Type 17, pro-inflammatory, Type 2 and regulatory cytokines and CC and CXC chemokines in PTB and latent TB (LTB) individuals with low BMI (LBMI) or normal BMI (NBMI).

Results

Our data show that PTB is associated with significantly lower levels of IFNγ, TNFα, IL-2, IL-17A, IL-6, IL-12, IL-4 and IL-5 cytokines but significantly higher levels of IL-10, TGFβ and GM-CSF in LBMI compared to NBMI. Similarly, PTB is also associated with significantly lower levels of CCL2, CCL3, CCL11, CXCL1, CXCL9 and CXCL10 chemokines in LBMI compared to NBMI. Our data reveals that LTB is associated with significantly lower levels of IFNγ, TNFα, IL-2, IL1β, IL-12, IL-13 cytokines but significantly higher levels of IL-10, TGFβ, IL-4 and IL-22 in LBMI compared to NBMI. Similarly, LTB is also associated with significantly lower levels of CCL2, CXCL1, CXCL9 and CXCL10 and significantly higher levels of CCL1, CCL3, and CCL4 in LBMI compared to NBMI.

Conclusion

Thus, LBMI has a major impact on the cytokine and chemokine milieu of both PTB and LTB and might predispose to the increased risk of tuberculosis by this immunomodulatory effect.

Advancing personalized medicine for tuberculosis through the application of immune profiling

While early and precise diagnosis is the key to eliminating tuberculosis (TB), conventional methods using culture conversion or sputum smear microscopy have failed to meet demand. This is especially true in high-epidemic developing countries and during pandemic-associated social restrictions. Suboptimal biomarkers have restricted the improvement of TB management and eradication strategies. Therefore, the research and development of new affordable and accessible methods are required. Following the emergence of many high-throughput quantification TB studies, immunomics has the advantages of directly targeting responsive immune molecules and significantly simplifying workloads. In particular, immune profiling has been demonstrated to be a versatile tool that potentially unlocks many options for application in TB management. Herein, we review the current approaches for TB control with regard to the potentials and limitations of immunomics. Multiple directions are also proposed to hopefully unleash immunomics' potential in TB research, not least in revealing representative immune biomarkers to correctly diagnose TB. The immune profiles of patients can be valuable covariates for model-informed precision dosing-based treatment monitoring, prediction of outcome, and the optimal dose prediction of anti-TB drugs.

Plasma cytokine levels characterize disease pathogenesis and treatment response in tuberculosis patients

BACKGROUND

Mycobacterium (M.) tuberculosis-caused immunopathology is characterized by aberrant expression of plasma cytokines in human tuberculosis. Disease severity and long-term anti-mycobacterial treatment are potentially influenced by immunopathology and normalization of plasma cytokine levels during therapy may indicate treatment efficacy and recovery.

STUDY DESIGN AND METHODS

In this study, we analyzed the concentrations of selected plasma cytokines (i.e., IL-6, IP-10, IL-10, IL-22, IFNγ, GM-CSF, IL-8) and M. tuberculosis sputum burden in patients with tuberculosis (n = 76). Cytokine levels were compared to healthy contacts (n = 40) and changes under treatment were monitored (i.e., 6 and 16 weeks after treatment start). According to differences in M. tuberculosis sputum burden and conversion, tuberculosis patients were classified as paucibacillary as well as 'rapid' or 'slow' treatment responders. A subgroup of tuberculosis patients had fatal disease courses.

RESULTS

Six of seven cytokines were significantly higher in tuberculosis patients as compared to contacts and four of these (i.e., IL-6, IP-10, IL-10, and IL-22) were detectable in the majority of tuberculosis patients. IL-6 showed the strongest discriminating capacity for tuberculosis disease and in combination with IL-10 concentrations efficiently classified paucibacillary tuberculosis cases as well as those with fatal disease outcome. In addition, IL-6 and IP-10 levels decreased significantly after 6 weeks of treatment and analyses of subgroups with differential treatment response showed delayed decline of IL-6 levels in slow treatment responders.

CONCLUSIONS

Combinations of different plasma cytokine (namely, IL-6, IL-10, and IP-10) efficiently classified tuberculosis patients with differential mycobacterial burden and especially IL-6 qualified as a biomarker candidate for early treatment response.

Investigation on Probable Association Between IL-13, IL-13RA1, and IL-13RA2 Genes Polymorphism and Pulmonary Tuberculosis

Objective

Our study aimed to explore the association of IL-13, IL-13RA1, and IL-13RA2 genes polymorphisms with PTB susceptibility and its clinical features.

Methods

Nine SNPs were genotyped by improved multiple ligase detection reaction (iMLDR) in 476 PTB patients and 473 controls. The association between these SNPs and PTB risk was analyzed using SPSS software and haplotype analysis was assessed using SHEsis software.

Results

The IL-13RA1 rs2495636 GA genotype frequency in PTB patients was significantly decreased, and IL-13RA2 rs5946039 A allele was related to the lower risk of PTB. In IL-13 gene, rs20541 variant was found to be associated with PTB risk under recessive mode. Moreover, IL-13RA1 rs141573089 C allele was significantly lower in PTB presenting with fever, drug resistance, and CC genotype was decreased in PTB presenting with leukopenia. IL-13RA1 rs2495636 polymorphism was associated with drug resistance, pulmonary infection, and IL-13RA2 rs3795175, rs638376 polymorphisms were related to drug resistance in PTB patients.

Conclusion

IL-13 rs20541, IL-13RA1 rs2495636, IL-13RA2 rs5946039 polymorphisms might be contributed to the genetic background of PTB in Chinese population.

Mycobacterium tuberculosis-Induced Upregulation of the COX-2/mPGES-1 Pathway in Human Macrophages Is Abrogated by Sulfasalazine

Macrophages are the primary human host cells of intracellular Mycobacterium tuberculosis (M.tb) infection, where the magnitude of inflammatory reactions is crucial for determining the outcome of infection. Previously, we showed that the anti-inflammatory drug sulfasalazine (SASP) significantly reduced the M.tb bactericidal burden and histopathological inflammation in mice. Here, we asked which genes in human inflammatory macrophages are affected upon infection with M.tb and how would potential changes impact the functional state of macrophages. We used a flow cytometry sorting system which can distinguish the dead and alive states of M.tb harbored in human monocyte-derived macrophages (MDM). We found that the expression of cyclooxygenase-2 and microsomal prostaglandin E₂ synthase (mPGES)-1 increased significantly in tagRFP⁺ MDM which were infected with alive M.tb. After exposure of polarized M1-MDM to M.tb (H37Rv strain)-conditioned medium (MTB-CM) or to the M.tb-derived 19-kD antigen, the production of PGE₂ and pro-inflammatory cytokines increased 3- to 4-fold. Upon treatment of M1-MDM with SASP, the MTB-CM-induced expression of COX-2 and the release of COX products and cytokines decreased. Elevation of PGE₂ in M1-MDM upon MTB-CM stimulation and modulation by SASP correlated with the activation of the NF-κB pathway. Together, infection of human macrophages by M.tb strongly induces COX-2 and mPGES-1 expression along with massive PGE₂ formation which is abrogated by the anti-inflammatory drug SASP.

Interleukin-37 gene polymorphism and susceptibility to pulmonary tuberculosis among Iraqi patients

BACKGROUND

Control of tuberculosis (TB) depends on a balance between host's immune factors and bacterial evasion strategies. Interleukin-37 (IL-37) is among the immunomodulatory factors that have been proposed to influence susceptibility to tuberculosis.

METHODS

A case-control study was conducted on 105 patients with pulmonary TB (37 active, 41 multi-drug resistant and 27 relapse) and 79 healthy controls to determine serum levels and single nucleotide polymorphisms (SNPs) of IL-37. The IL-37 level was assessed with an enzyme-linked immunosorbent kit, while DNA-sequencing was used to detect SNPs in the promoter region of IL37 gene.

RESULTS

Median level of IL-37 was markedly increased in serum of TB patients compared to controls (325.0 vs. 169.1 pg/mL; p < 0.001). This increase was universally determined in subgroups of patients distributed according to gender, age groups, and clinical type of disease, while no significant differences were found between the subgroups in patients or controls. Analysis of receiver operating characteristic curve confirmed these findings and IL-37 occupied a very good area under the curve, which was 0.816 (95% CI = 0.744-0.888; p < 0.001). At a cut-off value of 185.6 pg/mL, the sensitivity and specificity of IL-37 were 81.0 and 82.3%, respectively. Of the nine detected SNPs (rs2466449 G/A, rs2466450 A/G, rs2723168 G/A, rs3811042 G/A, rs3811045 T/C, rs3811046 G/T, rs3811047 A/G, rs3811048 G/A and rs200782323 G/A), only rs3811048 showed a significant association with TB; the G allele showed a significantly decreased frequency in TB patients compared to controls (25.2 vs. 44.9%; OR = 0.41; p < 0.001). It was possible to assign five haplotypes, and three showed significant differences between patients and controls. Frequency of haplotype A-A-G-A-C-T-G-A-G (0.331 vs. 0.213; OR = 2.10; p = 0.015) was significantly increased in TB patients compared to controls. On the contrary, frequencies of haplotypes A-A-G-A-C-T-G-G-G (0.029 vs. 0.116; OR = 0.24; p = 0.01) and A-A-G-G-T-G-A-G-G (0.140 vs. 0.275; OR = 0.45; p = 0.015) were significantly decreased in patients.

CONCLUSIONS

IL-37 was up-regulated in the serum of TB patients irrespective of their gender, age or clinical type of disease. SNPs in the promoter region of IL37 gene were proposed to be associated with susceptibility to TB.

Identification of Serum Cytokine Biomarkers Associated with Multidrug Resistant Tuberculosis (MDR-TB)

Existing tools (including GeneXpert) for diagnosis of multidrug resistant TB (MDR-TB) have limited utility when sputum samples for microbiological analyses cannot be obtained. There is the need for immunological biomarkers which could serve as putative diagnostic markers of MDR-TB. We measured and compared the serum cytokine levels of inflammatory cytokines (IFN-γ, TNF-α, IL12p70, IL-17A, granzyme B) and anti-inflammatory cytokines (IL-10, IL-6, IL-4) among MDR-TB, drug-susceptible (DS)-TB and healthy controls (no-TB) using the Human Magnetic Luminex Multiplex Immunoassay. Levels of IFN-γ and IL-4 were respectively 1.5 log lower and 1.9 log higher in MDR-TB compared to DS-TB cases. Moreover, IFN-γ, TNF-α, IL-10, IL-6, and IL-4 levels were significantly higher in individuals with MDR-TB and DS-TB cases compared to healthy controls. Pairs of cytokines, IL-4 and IFN-γ (p = 0.019), IL-4 and TNF (p = 0.019), and Granzyme B and TNF-α (p = 0.019), showed significant positive correlation in MDR-TB. Serum cytokine profiles can be exploited for immunodiagnostics, as made evident by the Interferon Gamma Release Assays (IGRAs) for TB infection. Using area under the curve values, no single or multiple cytokine combinations could discriminate between DS- and MDR-TB in this study. Studies with a larger sample size and more cytokines could better address the issue.

Pedunculoside protects against LPS-induced mastitis in mice by inhibiting inflammation and maintaining the integrity of blood-milk barrier

Mastitis is a disease that seriously threatens the health of the mammary gland after delivery. Pedunculoside (PE) is the main bioactive component of Aquifoliaceae. The purpose of this experiment is to explore the effects of PE on mastitis and its underlying mechanisms. Our research results showed that PE could significantly inhibit the increase in the levels of inflammatory mediators such as TNF-α, IL-6, IL-1β, MPO and iNOS during mastitis. Mechanism studies have found that PE could significantly inhibit the phosphorylation of AKT protein and binds to the ASP-184 site. Further research found that PE also inhibited the activation of AKT's downstream pro-inflammatory signals NF-κB and MAPK. In addition, PE effectively promote the expression of tight junction proteins occludin and claudin-3 during inflammation, maintaining the integrity of the blood-milk barrier. In summary, our research shows that PE inhibits the phosphorylation of AKT/NF-κB and MAPK signals; It also relieves mastitis by repairing the blood-milk barrier.

Lipoarabinomannan as a Point-of-Care Assay for Diagnosis of Tuberculosis: How Far Are We to Use It?

Tuberculosis (TB) is still a severe public health problem; the current diagnostic tests have limitations that delay treatment onset. Lipoarabinomannan (LAM) is a glycolipid that is a component of the cell wall of the bacillus Mycobacterium tuberculosis, the etiologic agent of TB. This glycolipid is excreted as a soluble form in urine. The World Health Organization has established that the design of new TB diagnostic methods is one of the priorities within the EndTB Strategy. LAM has been suggested as a biomarker to develop diagnostic tests based on its identification in urine, and it is one of the most prominent candidates to develop point-of-care diagnostic test because urine samples can be easily collected. Moreover, LAM can regulate the immune response in the host and can be found in the serum of TB patients, where it probably affects a wide variety of host cell populations, consequently influencing the quality of both innate and adaptive immune responses during TB infection. Here, we revised the evidence that supports that LAM could be used as a tool for the development of new point-of-care tests for TB diagnosis, and we discussed the mechanisms that could contribute to the low sensitivity of diagnostic testing.

The regulatory function of mixed lineage kinase 3 in tumor and host immunity

Protein kinases are the second most sought-after G-protein coupled receptors as drug targets because of their overexpression, mutations, and dysregulated catalytic activities in various pathological conditions. Till 2019, 48 protein kinase inhibitors have received FDA approval for the treatment of multiple illnesses, of which the majority of them are indicated for different malignancies. One of the attractive sub-group of protein kinases that has attracted attention for drug development is the family members of MAPKs that are recognized to play significant roles in different cancers. Several inhibitors have been developed against various MAPK members; however, none of them as monotherapy has shown sustainable efficacy. One of the MAPK members, called Mixed Lineage Kinase 3 (MLK3), has attracted considerable attention due to its role in inflammation and neurodegenerative diseases; however, its role in cancer is an emerging area that needs more investigation. Recent advances have shown that MLK3 plays a role in cancer cell survival, migration, drug resistance, cell death, and tumor immunity. This review describes how MLK3 regulates different MAPK pathways, cancer cell growth and survival, apoptosis, and host's immunity. We also discuss how MLK3 inhibitors can potentially be used along with immunotherapy for different malignancies.

Altered plasma levels of βC and γC chain cytokines and post-treatment modulation in tuberculous lymphadenitis

BACKGROUND

Alterations in β common (βC) and γ common (γC) chain cytokines have been described in pulmonary tuberculosis. However, their role in tuberculous lymphadenitis (TBL) disease has not been assessed.

METHODS

Thus, in the present study, we have examined the systemic levels of βC and γC chain cytokines in TBL, latent tuberculosis (LTB) and healthy control (HC) individuals. We have examined the discriminatory potential of both family of cytokines using ROC analysis. Finally, we measured the pre and post-treatment responses of these cytokines after anti-tuberculosis treatment.

RESULTS

TBL individuals exhibit significantly increased (IL-3) and diminished systemic levels of (IL-5, GM-CSF) βC cytokines compared to LTB and HC individuals. TBL individuals also exhibit significantly diminished (IL-2, IL-7) and elevated (IL-4, IL-9) levels of γC cytokines compared to LTB and/or HC. ROC analysis shows a clear discriminatory capacity of both βC (IL-5) and γC (IL-2) chain cytokines to distinguish TBL from LTB and HCs. The systemic levels of βC chain cytokines were not significantly altered, but in contrast γC (IL-2 and IL-7) cytokines were significantly modulated after treatment. Finally, no significant correlation was observed for βC and γC chain cytokines with their respective lymphocyte count of TBL individuals.

CONCLUSIONS

Hence, we conclude that altered plasma levels of βC and γC cytokines are the characteristics of immune alteration in TBL disease and certain cytokines were modulated after treatment.