Evaluation of IL-2, IL-10, IL-17 and IP-10 as potent discriminative markers for active tuberculosis among pulmonary tuberculosis suspects

Therapeutic Drug Monitoring and Biomarkers; towards Better Dosing of Antimicrobial Therapy

Due to variability in pharmacokinetics and pharmacodynamics, clinical outcomes of antimicrobial drug therapy vary between patients. As such, personalised medication management, considering both pharmacokinetics and pharmacodynamics, is a growing concept of interest in the field of infectious diseases. Therapeutic drug monitoring is used to adjust and individualise drug regimens until predefined pharmacokinetic exposure targets are achieved. Minimum inhibitory concentration (drug susceptibility) is the best available pharmacodynamic parameter but is associated with many limitations. Identification of other pharmacodynamic parameters is necessary. Repurposing diagnostic biomarkers as pharmacodynamic parameters to evaluate treatment response is attractive. When combined with therapeutic drug monitoring, it could facilitate making more informed dosing decisions. We believe the approach has potential and justifies further research.

A peptide-based vaccine ACP derived from antigens of Mycobacterium tuberculosis induced Th1 response but failed to enhance the protective efficacy of BCG in mice

BACKGROUND

Tuberculosis (TB) is a global infectious disease, but there is no ideal vaccine against TB except the Bacille Calmette-Guérin (BCG) vaccine.

METHODS

Herein, 25 candidate peptides were predicted from four antigens of Mycobacterium tuberculosis based on their high-affinity binding capacity for the human leukocyte antigen (HLA) DRB1∗0101. Three T-helper 1 (Th1) immunodominant peptides (Ag85B_12-26, CFP21_12-26, and PPE18_149-163) were identified by ELISPOT assays in the humanized C57BL/6 mice. They resulted in a novel Th1 peptide-based vaccine ACP named by the first letter of the three peptides. In addition, the protective efficacy was evaluated in humanized or wild-type C57BL/6 mice and the humoral and cellular immune responses were confirmed in vitro.

RESULTS

Compared with the PBS group, the ACP vaccinated mice showed slight decreases in colony-forming units (CFUs) and pathological lesions. However, when using it as a booster, the ACP vaccine did not significantly enhance the protective efficacy of BCG in humanized or wild-type mice. Interestingly, we found that ACP vaccination significantly increased the number of interferon-γ positive (IFN-γ⁺) T lymphocytes and the levels of IFN-γ cytokines as well as antibodies. Furthermore, the IL-2 level was significantly higher in humanized mice prime-boosted with BCG and ACP.

CONCLUSIONS

Our results suggested that ACP vaccination could stimulate higher levels of cytokines and antibodies but failed to improve the protective efficacy of BCG in mice, indicating that the secretion level of IFN-γ may not be positively correlated with the protection efficiency of the vaccine. These findings provided important information on the feasibility of a peptide vaccine as a booster for enhancing the protective efficacy of BCG.

Evaluation of tuberculosis diagnostic biomarkers in immunocompromised hosts based on cytokine levels in QuantiFERON-TB Gold Plus

Tuberculosis (TB) remains a serious health concern globally. QuantiFERON-TB (QFT) is a diagnostic tool for TB detection, and its sensitivity is reduced in immunocompromised hosts with low T lymphocyte counts or abnormal T cell function. This study aimed to evaluate the correlation between T cell and cytokine levels in patients with active TB using QFT-Plus. Forty-five patients with active TB were enrolled, and the cytokines in QFT-Plus tube supernatants were quantified using the MAGPIX System. CD4⁺ T cell count negatively correlated with patient age (p < 0.001, r = -0.51). The levels of TB1-responsive interleukin-1 receptor antagonist (IL-1Ra) and IL-2 correlated with CD4⁺ T cell count, whereas the levels of TB2-responsive IL-1Ra and IFN-γ-induced protein 10 correlated with both CD4⁺ and CD8⁺ T cell counts. Cytokines that correlated with CD4⁺ and CD8⁺ T cell counts might not be suitable TB diagnostic biomarkers in immunocompromised hosts. Notably, cytokines that did not correlate with the T cell counts, such as monocyte chemoattractant protein-1, might be candidate biomarkers for TB in immunocompromised hosts. Our findings might help improve TB diagnosis, which could enable prompt treatment and minimize poor disease outcomes.

Challenges and Future of Drug-Induced Liver Injury Research-Laboratory Tests

Drug-induced liver injury (DILI) is a rare but potentially severe adverse drug event, which is also a major cause of study cessation and market withdrawal during drug development. Since no acknowledged diagnostic tests are available, DILI diagnosis poses a major challenge both in clinical practice as well as in pharmacovigilance. Differentiation from other liver diseases and the identification of the causative agent in the case of polymedication are the main issues that clinicians and drug developers face in this regard. Thus, efforts have been made to establish diagnostic testing methods and biomarkers in order to safely diagnose DILI and ensure a distinguishment from alternative liver pathologies. This review provides an overview of the diagnostic methods used in differential diagnosis, especially with regards to autoimmune hepatitis (AIH) and drug-induced autoimmune hepatitis (DI-AIH), in vitro causality methods using individual blood samples, biomarkers for diagnosis and severity prediction, as well as experimental predictive models utilized in pre-clinical settings during drug development regimes.

Circulatory Inflammatory Mediators in the Prediction of Anti-Tuberculous Drug-Induced Liver Injury Using RUCAM for Causality Assessment

BACKGROUND

Anti-tuberculous (TB) medications are common causes of drug-induced liver injury (DILI). Limited data are available on systemic inflammatory mediators as biomarkers for predicting DILI before treatment. We aimed to select predictive markers among potential candidates and to formulate a predictive model of DILI for TB patients.

METHODS

Adult active TB patients from a prospective cohort were enrolled, and all participants received standard anti-tuberculous treatment. Development of DILI, defined as ≥5× ULN for alanine transaminase or ≥2.6× ULN of total bilirubin with causality assessment (RUCAM, Roussel Uclaf causality assessment method), was regularly monitored. Pre-treatment plasma was assayed for 15 candidates, and a set of risk prediction scores was established using Cox regression and receiver-operating characteristic analyses.

RESULTS

A total of 19 (7.9%) in 240 patients developed DILI (including six carriers of hepatitis B virus) following anti-TB treatment. Interleukin (IL)-22 binding protein (BP), interferon gamma-induced protein 1 (IP-10), soluble CD163 (sCD163), IL-6, and CD206 were significant univariable factors associated with DILI development, and the former three were backward selected as multivariable factors, with adjusted hazards of 0.20 (0.07-0.58), 3.71 (1.35-10.21), and 3.28 (1.07-10.06), respectively. A score set composed of IL-22BP, IP-10, and sCD163 had an improved area under the curve of 0.744 (p < 0.001).

CONCLUSIONS

Pre-treatment IL-22BP was a protective biomarker against DILI development under anti-TB treatment, and a score set by additional risk factors of IP-10 and sCD163 employed an adequate DILI prediction.

The Diagnostic Value of Blood and Urine IP-10 Test in Children Having Active Tuberculosis or Latent Tuberculosis Infection

Objective This study aimed to investigate interferon-gamma-inducible protein-10 (IP-10) values in serum and urine in pediatric patients in the diagnosis of active tuberculosis (TB) or latent TB infection (LTBI). It also aimed to investigate whether it can be used as a biomarker to distinguish between active TB and LTBI.

Methods Our study comprised active TB (25 patients), LTBI (25 patients), and the “infected” group (50 patients) formed by combining the two groups. As the control group, 37 healthy children were included in the study. TB skin test, plasma IP-10, and urine IP-10 measurements were performed in all patients included in the study. An additional QuantiFERON-TB Gold In-Tube (QFT-GIT) test was performed on patients evaluated as active TB or LTBI.

Results Plasma IP-10 levels of the patients in the active TB, LTBI, and the “infected” groups were significantly higher than the control group (p = 0.022, p = 0.028, and p = 0.007, respectively). Urine IP-10 was successful in distinguishing the active TB and “infected” groups from the control group (p = 0.007 and p = 0.047, respectively). Also, in the combined use of the tests, when QFT-GIT and urine IP-10 were positive together, active TB and LTBI could be distinguished (p = 0.044). Urine IP-10 levels were found to be significantly higher in those with pulmonary TB than those with extrapulmonary TB (p = 0.012).

Conclusion Our findings suggest that IP-10 can be used as a useful biomarker in the diagnosis of active TB in children.

Different PPD-stimulated cytokine responses from patients infected with genetically distinct Mycobacterium tuberculosis complex lineages

OBJECTIVES

The genetic diversity of Mycobacterium tuberculosis complex (MTBC) influences the immune response of the host, which may affect the immunodiagnostic tests and biomarker assessment studies used for tuberculosis (TB). This study aimed to determine whether the mycobacterial-antigen-stimulated cytokine responses vary with the genotype of the MTBC infecting the patient.

METHODS

Eighty-one patients with confirmed active pulmonary TB were recruited, and MTBC clinical strains were isolated from their sputum for bacterial lineage single-nucleotide polymorphism typing. Whole blood was drawn from the patients to measure the purified protein derivative (PPD)-stimulated cytokine responses (GM-CSF, IFN-γ, IL-1β, IL-2, IL-4, IL-5, IL-6, IL-7, IL-8, IL-10, TNF-α, IFN-α, IL-12, eotaxin, IL-13, IL-15, IL-17, MIP1-α, MIP1-β, MCP1, IL1RA, IP10, IL2R, MIG) with the Luminex multiplex immunoassay.

RESULTS

Of the 24 cytokines studied, three were produced differentially in whole blood dependent on the infecting lineage of MTBC. Decreased production of IL-17 was observed in patients infected with modern lineages compared with patients infected with ancestral lineages (P < 0.01), and production of IFN-γ and IL-2 was significantly decreased in patients infected with lineage 4 strains compared with patients infected with lineage 3 strains (P < 0.05).

CONCLUSION

MTBC strains belonging to lineage 4 induced a decreased whole-blood PPD-stimulated pro-inflammatory cytokine response.

Evaluation of cytokines as a biomarker to distinguish active tuberculosis from latent tuberculosis infection: a diagnostic meta-analysis

OBJECTIVES

With a marginally effective vaccine and no significant breakthroughs in new treatments, a sensitive and specific method to distinguish active tuberculosis from latent tuberculosis infection (LTBI) would allow for early diagnosis and limit the spread of the pathogen. The analysis of multiple cytokine profiles provides the possibility to differentiate the two diseases.

DESIGN

Systematic review and meta-analysis.

DATA SOURCES

PubMed, Cochrane Library, Clinical Key and EMBASE databases were searched on 31 December 2019.

ELIGIBILITY CRITERIA

We included case-control studies, cohort studies and randomised controlled trials considering IFN-γ, TNF-α, IP-10, IL-2, IL-10, IL-12 and VEGF as biomarkers to distinguish active tuberculosis and LTBI.

DATA EXTRACTION AND SYNTHESIS

Two students independently extracted data and assessed the risk of bias. Diagnostic OR, sensitivity, specificity, positive and negative likelihood ratios and area under the curve (AUC) together with 95% CI were used to estimate the diagnostic value.

RESULTS

Of 1315 records identified, 14 studies were considered eligible. IL-2 had the highest sensitivity (0.84, 95% CI: 0.72 to 0.92), while VEGF had the highest specificity (0.87, 95% CI: 0.73 to 0.94). The highest AUC was observed for VEGF (0.85, 95% CI: 0.81 to 0.88), followed by IFN-γ (0.84, 95% CI: 0.80 to 0.87) and IL-2 (0.84, 95% CI: 0.81 to 0.87).

CONCLUSION

Cytokines, such as IL-2, IFN-γ and VEGF, can be utilised as promising biomarkers to distinguish active tuberculosis from LTBI.

PROSPERO REGISTRATION NUMBER

CRD42020170725.

Mycobacterium tuberculosis-specific cytokine biomarkers to differentiate active TB and LTBI: A systematic review

OBJECTIVES

New tests are needed to overcome the limitations of existing immunodiagnostic tests for tuberculosis (TB) infection, including their inability to differentiate between active TB and latent TB infection (LTBI). This review aimed to identify the most promising cytokine biomarkers for use as stage-specific markers of TB infection.

METHODS

A systematic review was done using electronic databases to identify studies that have investigated Mycobacterium tuberculosis (MTB)-specific cytokine responses as diagnostic tools to differentiate between LTBI and active TB.

RESULTS

The 56 studies included in this systematic review measured the MTB-specific responses of 100 cytokines, the most frequently studied of which were IFN-γ, IL-2, TNF-α, IP-10, IL-10 and IL-13. Ten studies assessed combinations of cytokines, most commonly IL-2 and IFN-γ. For most cytokines, findings were heterogenous between studies. The variation in results likely relates to differences in the study design and laboratory methods, as well as participant and environmental factors.

CONCLUSIONS

Although several cytokines show promise as stage-specific markers of TB infection, this review highlights the need for further well-designed studies, in both adult and paediatric populations, to establish which cytokine(s) will be of most use in a new generation of immunodiagnostic tests.

The combination of CXCL9, CXCL10 and CXCL11 levels during primary HIV infection predicts HIV disease progression

Background

Chemokines are small chemotactic cytokines involved in inflammation, cell migration, and immune regulation in both physiological and pathological contexts. Here, we investigated the profile of chemokines during primary HIV infection (PHI).

Methods

Fifty-four participants with blood samples before and during HIV infection and clinical information available were selected from an HIV-negative man who have sex with men (MSM) prospective cohort. Thirty chemokines and 10 cytokines were measured pre- and post-HIV infection in the same individuals using a Bio-Plex Pro™ Human Chemokine Panel.

Results

Levels of 18 chemokines/cytokines changed significantly during PHI relative to pre-HIV infection levels; 14 were up-regulated and 4 down-regulated. Among them, CXCL9, CXCL10, and CXCL11 were the most prominently raised. Levels of CXCL9 and CXCL10 were much higher in the high-set point group (log viral load (lgVL) ≥ 4.5) than those in the low-set point group (lgVL < 4.5) and levels of CXCL9, CXCL10, and CXCL11 were higher in the low-CD4⁺ T-cell count group (CD4⁺ T-cell count ≥ 500). A formula to predict HIV disease progression using a combination panel comprising CXCL9, CXCL10, and CXCL11 was developed, where risk score = 0.007 × CXCL9 + 0.004 × CXCL10 − 0.033 × CXCL11 − 1.724, with risk score values higher than the cutoff threshold (0.5211) indicating more rapid HIV disease progression.

Conclusions

A panel of plasma CXCL9, CXCL10, and CXCL11 measured during primary HIV-1 infection could predict long-term HIV disease prognosis in an MSM group and has potential as a novel biomarker in the clinic.

IL-2 Restores T-Cell Dysfunction Induced by Persistent Mycobacterium tuberculosis Antigen Stimulation

Tuberculosis (TB) is a chronic disease mainly caused by Mycobacterium tuberculosis. The function of T cells usually decreased and even exhausted in severe TB such as multiple drug resistant TB (MDR-TB), which might lead to the failure of treatment in return. The mechanism of T cell dysfunction in TB is still not clear. In this study we set up a mouse model of T cell dysfunction by persistent M. tuberculosis antigen stimulation and investigated the therapeutic role of interleukin 2 (IL-2) in it. C57BL/6 mice were primed with Mycobacterium bovis Bacillus Calmette-Guérin (BCG) and boosted repeatedly with a combination of M. tuberculosis fusion proteins Mtb10.4-HspX (MH) plus ESAT6-Ag85B-MPT64 _<190-198>-Mtb8.4-Rv2626c (LT70) or MH plus ESAT6 and CFP10 with adjuvant of N, N'-dimethyl-N, N'-dioctadecylammonium bromide (DDA) plus polyinosinic-polycytidylic acid (Poly I:C). Following persistent antigen stimulation, the mice were treated with IL-2 and the therapeutic effects were analyzed. The results showed that compared with the mice that received transient antigen stimulation (boost twice), persistent antigen stimulation (boost more than 10 times) resulted in decrease of antigen specific IFN-γ and IL-2 production, reduction of memory CD8⁺ T cells, over-expression of immune checkpoint programmed cell death protein 1 (PD-1), and impaired the protective immunity against bacterial challenge. Treating the T cell functionally exhausted mice with IL-2 restored antigen-specific T cell responses and protective efficacy. In conclusion, persistent stimulation with M. tuberculosis antigens induced T cell dysfunction, which could be restored by complement of IL-2.

A systematic review of biomarkers to detect active tuberculosis

Millions of cases of tuberculosis (TB) go undiagnosed each year. Better diagnostic tools are urgently needed. Biomarker-based or multiple marker biosignature-based tests, ideally performed on blood or urine, for the detection of active TB might help to meet target product profiles proposed by the World Health Organization for point-of-care testing. We conducted a systematic review to summarize evidence on proposed biomarkers and biosignatures and evaluate their quality and level of evidence. We screened the titles and abstracts of 7,631 citations and included 443 publications that fulfilled the inclusion criteria and were published in 2010-2017. The types of biomarkers identified included antibodies, cytokines, metabolic activity markers, mycobacterial antigens and volatile organic compounds. Only 47% of studies reported a culture-based reference standard and diagnostic sensitivity and specificity. Forty-four biomarkers (4%) were identified in high-quality studies and met the target product profile minimum criteria, of which two have been incorporated into commercial assays. Of the 44 highest-quality biomarkers, 24 (55%) were multiple marker biosignatures. No meta-analyses were performed owing to between-study heterogeneity. In conclusion, TB biomarker discovery studies are often poorly designed and findings are rarely confirmed in independent studies. Few markers progress to a further developmental stage. More validation studies that consider the intended diagnostic use cases and apply rigorous design are needed. The extracted data from this review are currently being used by FIND as the foundation of a dynamic database in which biomarker data and developmental status will be presented.

Using cytometric bead arrays to detect cytokines in the serum of patients with different types of pulmonary tuberculosis

Cytokines play a crucial role in mediating immune responses to tuberculosis (TB). The aim of this study was to evaluate the levels of cytokines in patients with different forms of pulmonary tuberculosis (PTB) and identify valuable cytokine biomarkers for the diagnosis of PTB. We measured the levels of six cytokines (interleukin (IL-2, IL-4, IL-6, and IL-10), tumor necrosis factor (TNF-α), and interferon-γ (IFN-γ)) in the serum of healthy donors (n = 30). Patients with active PTB (n = 46) and those with latent tuberculosis infection (LTBI, n = 38) were examined using cytometric bead arrays. The levels of the six cytokines in the serum samples were measured promptly, sensitively, and simultaneously. The levels of IL-2, IL-6, IL-10, and IFN-γ were significantly higher in the PTB group compared with those reported in the healthy donors ( P < 0.01 or P < 0.05). In addition, significantly higher levels of IL-2, IL-6, IL-10, and IFN-γ were found in the active PTB group compared with those observed in the LTBI group ( P < 0.01 or P < 0.05). However, the levels of IL-4 and TNF-α in the sera of patients from the PTB group did not show a significant correlation with those measured in the healthy donor group. Our data demonstrated that IL-2, IL-6, IL-10, and IFN-γ may be useful in the auxiliary diagnosis of tuberculosis and as biomarkers for distinguishing LTBI from TB.

IP-10 and RANTES as biomarkers for pulmonary tuberculosis diagnosis and monitoring

OBJECTIVE

We aimed to determine whether IP-10 and RANTES plasma levels can be used in diagnosis and monitoring of pulmonary tuberculosis (PTB).

METHODS

Plasma levels of cytokines/chemokines were measured using a Bio-Plex^® multiplex cytokine assay system in a cohort containing 457 clinically suspected PTB patients including a training set (n = 41)and two independent test sets A (n = 242) and B (n = 174).

RESULTS

Plasma levels of IP-10 and RANTES were significantly higher in PTB patients than healthy controls' in both training and independent test sets (P < 0.05). Compared with other combinations, the combination of IP-10 and RANTES had the best performance with an AUC of 1.0 in training set. The performance characteristic of this model was successfully validated in independent test set A although this combination only resulted in a slightly improvement of AUC value in independent test set B. Plasma IP-10 and RANTES levels were weakly and positively correlated with blood glucose concentrations. Moreover, IP-10 levels were positively correlated with CRP and ESR in PTB patients. Furthermore, in response to therapy, both IP-10 and RANTES levels significantly decreased over the period of 6 months (P < 0.001).

CONCLUSIONS

Taken together, combination of IP-10 and RANTES could be potentially used as diagnostic and monitoring biomarker in PTB management.

Th1 cytokines, true functional signatures for protective immunity against TB?

The lack of an effective preventative vaccine against tuberculosis (TB) presents a great challenge to TB control. Since it takes an extremely long time to accurately determine the protective efficacy of TB vaccines, there is a great need to identify the surrogate signatures of protection to facilitate vaccine development. Unfortunately, antigen-specific Th1 cytokines that are currently used to evaluate the protective efficacy of the TB vaccine, do not align with the protection and failure of TB vaccine candidates in clinical trials. In this review, we discuss the limitation of current Th1 cytokines as surrogates of protection and address the potential elements that should be considered to finalize the true functional signatures of protective immunity against TB.

Chemokines and Chemokine Receptors: Accomplices for Human Immunodeficiency Virus Infection and Latency

Chemokines are small chemotactic cytokines that are involved in the regulation of immune cell migration. Multiple functional properties of chemokines, such as pro-inflammation, immune regulation, and promotion of cell growth, angiogenesis, and apoptosis, have been identified in many pathological and physiological contexts. Human immunodeficiency virus (HIV) infection is characterized by persistent inflammation and immune activation during both acute and chronic phases, and the "cytokine storm" is one of the hallmarks of HIV infection. Along with immune activation after HIV infection, an extensive range of chemokines and other cytokines are elevated, thereby generating the so-called "cytokine storm." In this review, the effects of the upregulated chemokines and chemokine receptors on the processes of HIV infection are discussed. The objective of this review was to focus on the main chemokines and chemokine receptors that have been found to be associated with HIV infection and latency. Elevated chemokines and chemokine receptors have been shown to play important roles in the HIV life cycle, disease progression, and HIV reservoir establishment. Thus, targeting these chemokines and receptors and the other proteins of related signaling pathways might provide novel therapeutic strategies, and the evidence indicates a promising future regarding the development of a functional cure for HIV.

Use of IFN-γ and IP-10 detection in the diagnosis of latent tuberculosis infection in patients with inflammatory rheumatic diseases

OBJECTIVES

Biologic agents are used against rheumatic diseases, however, they increase the risk of developing severe infections and diseases such as tuberculosis. We aimed to determine the benefits of IP-10 detection to diagnose latent tuberculosis infection (LTBI) in patients with inflammatory rheumatic diseases on different immunosuppressive drug regimens, and compare these results with IFN-γ detection.

MATERIALS AND METHODS

We included 64 patients with inflammatory rheumatic diseases. We used QuantiFERON Gold In-Tube (QFN-G-IT) and T-SPOT.TB to detect IFN-γ production, and an in-house ELISA for IP-10 detection from the previous QFN-G-IT stimulated samples. We assessed the combined use of IFN-γ release assays (IGRAs) and IP-10 test, and analyzed the influence of immunotherapy on the tests performance.

RESULTS

We obtained 34.9% positive results by T-SPOT.TB, 25.0% by QFN-G-IT and 31.3% by IP-10 test. The combined use of IGRAs and IP-10 detection increased significantly the amount of positive results (p < 0.0001). Treatment intake had no significant effect on in vitro tests (p > 0.05).

CONCLUSIONS

IP-10 and IFN-γ detection is comparable and their combined use could increase the number of positive results in the diagnosis of LTBI in rheumatic patients. The tested assays were not influenced by rheumatoid immunosuppressive therapy. Thus, IP-10 could be of use in the development of new and improved LTBI diagnostic tools.