Cytokine Kinetics in the First Week of Tuberculosis Therapy as a Tool to Confirm a Clinical Diagnosis and Guide Therapy

Biomarkers to predict FDG PET/CT activity after the standard duration of treatment for spinal tuberculosis: An exploratory study

OBJECTIVES

18F-Fluorodeoxyglucose (FDG) Positron Emission Tomography- Computed Tomography (PET/CT) scans can be used to assess healing following treatment for spinal tuberculosis (TB) but have limited accessibility and high cost. This study investigated the association between immune biomarkers and FDG-PET/CT activity after ≥9 months of treatment for spinal TB.

METHODS

Patients who had completed ≥9 months of treatment for spinal TB were recruited from a major hospital in the Western Cape, South Africa. Participants underwent a FDG-PET/CT scan and FDG- PET/CT activity was quantified for all spinal and extra-spinal sites. Participants also provided a blood sample, which was evaluated for 19 cytokines along with erythrocyte sedimentation rate (ESR). Correlations and multiple regression analyses were used to investigate the association between biomarkers and PET/CT measures.

RESULTS

Twenty-eight patients were recruited, of whom 24 (86%) had spinal and/or extra-spinal FDG-PET/CT activity. In the strongest multiple regression model, CXCL10/IP-10, VEGFA, IFN-γ, CRP and Factor D/Adipsin explained 52% of the variation in overall maximal FDG uptake. Conventional monitoring marker ESR showed no significant association with PET/CT measures.

CONCLUSIONS

The current findings offered encouragement that biomarkers to predict FDG-PET/CT activity may show some promise and identified candidate biomarkers for further investigation in this regard.

An Aptamer Linked Immobilized Sorbent Assay (ALISA) to Detect Circulatory IFN-α, an Inflammatory Protein among Tuberculosis Patients

Dysregulation of IFN-α is the basis for pathogenesis of autoimmune as well as infectious diseases. Identifying inflammatory signatures in peripheral blood of patients is an approach for monitoring active infection. Hence, estimation of type I IFNs as an inflammatory biomarker to scrutinize disease status after treatment is useful. Accordingly, an Aptamer Linked Immobilized Sorbent Assay (ALISA) for the detection of IFN-α in serum samples was developed. Sixteen aptamers were screened for their ability to bind IFN-α. Aptamer IFNα-3 exhibited specificity for IFN-α with no cross-reactivity with interferons β and γ and human serum albumin. The disassociation constant (K_d) was determined to be 3.96 ± 0.36 nM, and the limit of detection was ∼2 ng. The characterized IFNα-3 aptamer was used in ALISA to screen tuberculosis (TB) patients' sera. An elevated IFN-α level in sera derived from untreated TB patients (median = 0.31), compared to nontuberculous household contacts (median = 0.13) and healthy volunteers (median = 0.12), and further a decline in IFN-α level among treated patients (median = 0.13) were seen. The ALISA assay facilitates direct estimation of inflammatory protein(s) in circulation unlike mRNA estimation by real time PCR. Designing of aptamers similar to the IFNα-3 aptamer provides a novel approach to assess other inflammatory protein(s) in patients before, during, and after completion of treatment and would denote clinical improvement in successfully treated patients.

First description of agonist and antagonist IP-10 in urine of patients with active TB

OBJECTIVES

Biomarkers for tuberculosis (TB) diagnosis and clinical management are needed to defeat TB. In chronic hepatitis, patients not responding to interferon/ribavirin treatment had high levels of an antagonist form of IP-10. Recently, antagonist IP-10 has been shown to be involved also in TB pathogenesis. Here, we investigated IP-10 agonist/antagonist forms as potential inflammatory biomarkers to support TB diagnosis and monitoring.

METHODS

Total IP-10 and its agonist/antagonist forms were measured by SIMOA digital ELISA in urine obtained from patients with active TB at baseline and after treatment. Healthy donors (HD) and patients with pneumonia were enrolled as controls.

RESULTS

Patients with active TB had significantly higher levels of total and agonist IP-10 at baseline compared to HD; conversely, no differences were observed between IP-10 levels in active TB vs pneumonia. Moreover, in active TB a decline of total urine IP-10 was observed at therapy completion; agonist/antagonist forms reflected this decline although their differences were not statistically significant.

CONCLUSIONS

We showed for the first time that agonist/antagonist IP-10 forms are measurable in urine. IP-10 levels associate with TB and pneumonia disease, suggesting their association with acute inflammation. Further studies are needed to assess their role to monitor TB treatment efficacy.

Immune responses in the treatment of drug-sensitive pulmonary tuberculosis with phenylbutyrate and vitamin D3 as host directed therapy

Background

We have previously shown that 8 weeks’ treatment with phenylbutyrate (PBA) (500mgx2/day) with or without vitamin D₃ (vitD₃) (5000 IU/day) as host-directed therapy (HDT) accelerated clinical recovery, sputum culture conversion and increased expression of cathelicidin LL-37 by immune cells in a randomized, placebo-controlled trial in adults with pulmonary tuberculosis (TB). In this study we further aimed to examine whether HDT with PBA and vitD₃ promoted clinically beneficial immunomodulation to improve treatment outcomes in TB patients.

Methods

Cytokine concentration was measured in supernatants of peripheral blood mononuclear cells (PBMC) from patients (n = 31/group). Endoplasmic reticulum stress-related genes (GADD34 and XBP1spl) and human beta-defensin-1 (HBD1) gene expression were studied in monocyte-derived-macrophages (MDM) (n = 18/group) from PBMC of patients. Autophagy in MDM (n = 6/group) was evaluated using LC3 expression by confocal microscopy.

Results

A significant decline in the concentration of cytokines/chemokines was noted from week 0 to 8 in the PBA-group [TNF-α (β = − 0.34, 95% CI = − 0.68, − 0.003; p = 0.04), CCL11 (β = − 0.19, 95% CI = − 0.36, − 0.03; p = 0.02) and CCL5 (β = − 0.08, 95% CI = − 0.16, 0.002; p = 0.05)] and vitD₃-group [(CCL11 (β = − 0.17, 95% CI = − 0.34, − 0.001; p = 0.04), CXCL10 (β = − 0.38, 95% CI = − 0.77, 0.003; p = 0.05) and PDGF-β (β = − 0.16, 95% CI = − 0.31, 0.002; p = 0.05)] compared to placebo. Both PBA- and vitD₃-groups showed a decline in XBP1spl mRNA on week 8 (p < 0.03). All treatment groups demonstrated increased LC3 expression in MDM compared to placebo over time (p < 0.037).

Conclusion

The use of PBA and vitD₃ as adjunct therapy to standard TB treatment promoted favorable immunomodulation to improve treatment outcomes.

Trials registration

This trial was retrospectively registered in clinicaltrials.gov, under identifier NCT01580007.

Electronic supplementary material

The online version of this article (10.1186/s12879-018-3203-9) contains supplementary material, which is available to authorized users.

Inflammatory cytokine profiles of serum and cerebrospinal fluid in Chinese children with hand, foot and mouth disease

OBJECTIVE

Hand, foot and mouth disease (HFMD) is mainly caused by enterovirus 71 (EV71) or coxsackie virus A16 infection. Severe HFMD with encephalitis is a life-threatening disease for children. This study aimed to examine the levels of a variety of inflammatory cytokines in HFMD patients.

METHODS

Sera of severe or common HFMD patients and cerebrospinal fluids from severe HFMD patients in the acute or recovery phase were collected to analyse 40 cytokines using the Raybiotec Cytokine array. Twenty-six samples of sera or cerebrospinal fluids from HFMD patients were further detected using Milliplex beads.

RESULTS

Numerous inflammatory cytokines, such as IL-8, IP-10, and RAENTES, were enhanced in the sera and cerebrospinal fluids of encephalitis-complicated HFMD patients. Serum IL-12p40 and IL-15 levels were higher in severe HFMD patients compared with common patients. Moreover, IL-8 and IP-10 levels in the cerebrospinal fluid were sharply enhanced by 30-fold on average compared with those in the sera. Cerebrospinal fluid IL-8, IP-10, and RANTES levels were significantly enhanced in the acute phase of severe HFMD patients compared with those in the recovery phase. However, no correlation of serum IL-8 or IP-10 level with its cerebrospinal fluid level was observed.

CONCLUSION

An inflammatory cytokine storm occurs both in sera and cerebrospinal fluids during severe HFMD, which is likely a Th1 cell-associated disease. Cerebrospinal fluid IL-8, IP-10 and RANTES levels could be used as potential biomarkers for diagnosing severe HFMD, whereas the enhanced serum levels of IL-12p40 and IL-15 could be used as candidate predictive factors for severe HFMD.

IP-10 Kinetics in the First Week of Therapy are Strongly Associated with Bacteriological Confirmation of Tuberculosis Diagnosis in HIV-Infected Patients

Simple effective tools to monitor the long treatment of tuberculosis (TB) are lacking. Easily measured host derived biomarkers have been identified but need to be validated in larger studies and different population groups. Here we investigate the early response in IP-10 levels (between day 0 and day 7 of TB therapy) to identify bacteriological status at diagnosis among 127 HIV-infected patients starting TB treatment. All participants were then classified as responding or not responding to treatment blindly using a previously described IP-10 kinetic algorithm. There were 77 bacteriologically confirmed cases and 41 Xpert MTB/RIF® and culture negative cases. Most participants had a measurable decline in IP-10 during the first 7 days of therapy. Bacteriologically confirmed cases were more likely to have high IP-10 levels at D0 and had a steeper decline than clinically diagnosed cases (mean decline difference 2231 pg/dl, 95% CI: 897–3566, p = 0.0013). Bacteriologically confirmed cases were more likely to have a measurable decline in IP-10 at day 7 than clinically diagnosed cases (48/77 (62.3%) vs 13/41 (31.7%), p < 0.001). This study confirms the association between a decrease in IP-10 levels during the first week of treatment and a bacteriological confirmation at diagnosis in a large cohort of HIV positive patients.

Interleukin-1 receptor antagonist, a biomarker of response to anti-TB treatment in HIV/TB co-infected patients

OBJECTIVES

Despite the high frequency of tuberculosis-associated immune reconstitution inflammatory syndrome (TB-IRIS) in human immunodeficiency virus (HIV)/TB co-infected patients, no diagnostic test is available. Here, we investigated whether monocyte/macrophage activation markers can predict TB-IRIS occurrence and if they are modulated by anti-TB treatment.

METHODS

Frozen plasma was obtained from 127 HIV/TB co-infected adults naïve for antiretroviral therapy, enrolled in the CAMELIA trial, 36 of whom developed TB-IRIS. Concentrations of IL-1Ra, sCD14, and sCD163 were measured at anti-TB treatment onset (baseline), after 8 weeks of anti-TB treatment and at TB-IRIS time.

RESULTS

At baseline, IL-1Ra and sCD14 concentrations were similar in TB-IRIS and non-IRIS patients. sCD163 concentrations, although significantly higher in TB-IRIS patients, did not remain associated with TB-IRIS occurrence in multivariate analysis. At the time of TB-IRIS, patients displayed higher concentrations of IL-1Ra (p = 0.002) and sCD14 (p < 0.001). The most striking result was the significant decrease in IL-1Ra after 8 weeks of anti-TB treatment (median reduction: -63% (p < 0.0001)).

CONCLUSIONS

None of the biomarkers tested was associated with TB-IRIS occurrence. However, repeated measurement of IL-1Ra could help for the diagnosis of TB-IRIS. The substantial reduction of IL-1Ra under treatment suggests that IL-1Ra could be a surrogate biomarker of anti-TB treatment response in HIV-infected patients.

Individualizing management of extensively drug-resistant tuberculosis: diagnostics, treatment, and biomarkers

INTRODUCTION

Success rates for treatment of extensively drug resistant tuberculosis (XDR-TB) are low due to limited treatment options, delayed diagnosis and inadequate health care infrastructure. Areas covered: This review analyses existing programmes of prevention, diagnosis and treatment of XDR-TB. Improved diagnostic procedures and rapid molecular tests help to select appropriate drugs and dosages. Drugs dosages can be further tailored to the specific conditions of the patient based on quantitative susceptibility testing of the M. tuberculosis isolate and use of therapeutic drug monitoring. Pharmacovigilance is important for preserving activity of the novel drugs bedaquiline and delamanid. Furthermore, biomarkers of treatment response must be developed and validated to guide therapeutic decisions. Expert commentary: Given the currently poor treatment outcomes and the association of XDR-TB with HIV in endemic regions, a more patient oriented approach regarding diagnostics, drug selection and tailoring and treatment evaluation will improve treatment outcome. The different areas of expertise should be covered by a multidisciplinary team and may involve the transition of patients from hospitalized to home or community-based treatment.

Tuberculosis Biomarkers: From Diagnosis to Protection

New approaches to control tuberculosis (TB) worldwide are needed. In particular, new tools for diagnosis and new biomarkers are required to evaluate both pathogen and host key elements of the response to infection. Non-sputum based diagnostic tests, biomarkers predictive of adequate responsiveness to treatment, and biomarkers of risk of developing active TB disease are major goals. Here, we review the current state of the field. Although reports on new candidate biomarkers are numerous, validation and independent confirmation are rare. Efforts are needed to reduce the gap between the exploratory up-stream identification of candidate biomarkers, and the validation of biomarkers against clear clinical endpoints in different populations. This will need a major commitment from both scientists and funding bodies.