Summary Background We aimed to understand host factors that affect discriminatory performance of a transcriptomic signature of tuberculosis risk (RISK11). Methods HIV-negative adults aged 18–60 years were evaluated in a prospective study... more
Summary Background We aimed to understand host factors that affect discriminatory performance of a transcriptomic signature of tuberculosis risk (RISK11). Methods HIV-negative adults aged 18–60 years were evaluated in a prospective study of RISK11 and surveilled for tuberculosis through 15 months. Generalised linear models and receiver-operating characteristic (ROC) regression were used to estimate effect of host factors on RISK11 score (%marginal effect) and on discriminatory performance for tuberculosis disease (area under the curve, AUC), respectively. Findings Among 2923 participants including 74 prevalent and 56 incident tuberculosis cases, percentage marginal effects on RISK11 score were increased among those with prevalent tuberculosis (+18·90%, 95%CI 12·66−25·13), night sweats (+14·65%, 95%CI 5·39−23·91), incident tuberculosis (+7·29%, 95%CI 1·46−13·11), flu-like symptoms (+5·13%, 95%CI 1·58−8·68), and smoking history (+2·41%, 95%CI 0·89−3·93) than those without; and reduced in males (−6·68%, 95%CI −8·31−5·04) and with every unit increase in BMI (−0·13%, −95%CI −0·25−0·01). Adjustment for host factors affecting controls did not change RISK11 discriminatory performance. Cough was associated with 72·55% higher RISK11 score in prevalent tuberculosis cases. Stratification by cough improved diagnostic performance from AUC = 0·74 (95%CI 0·67−0·82) overall, to 0·97 (95%CI 0·90−1·00, p < 0·001) in cough-positive participants. Combining host factors with RISK11 improved prognostic performance, compared to RISK11 alone, (AUC = 0·76, 95%CI 0·69−0·83 versus 0·56, 95%CI 0·46−0·68, p < 0·001) over a 15-month predictive horizon. Interpretation Several host factors affected RISK11 score, but only adjustment for cough affected diagnostic performance. Combining host factors with RISK11 should be considered to improve prognostic performance. Funding Bill and Melinda Gates Foundation, South African Medical Research Council.
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Research Interests: Immunology, Flow Cytometry, Cytokines, Saponins, Adolescent, and 15 moreMedicine, Biological Sciences, Humans, Mycobacterium tuberculosis, Natural Killer cells, Female, Male, Endemic Diseases, Placebos, Clinical Sciences, Lipid A, Immunogenicity, Medical and Health Sciences, Paediatrics and reproductive medicine, and Drug combinations
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Research Interests: Immunology, Biology, Virology, Medicine, Disease, and 4 moreCytomegalovirus, CD, Risk Factor, and Immune system
Heterologous prime-boost strategies hold promise for vaccination against tuberculosis. However, the T-cell characteristics required for protection are not known. We proposed that boost vaccines should induce long-lived functional and... more
Heterologous prime-boost strategies hold promise for vaccination against tuberculosis. However, the T-cell characteristics required for protection are not known. We proposed that boost vaccines should induce long-lived functional and phenotypic changes to T cells primed by Bacille Calmette Guerin (BCG) and/or natural exposure to mycobacteria. We characterized changes among specific CD4+ T cells after vaccination with the MVA85A vaccine in adults, adolescents, and children. CD4+ T cells identified with Ag85A peptide-bearing HLA class II tetramers were characterized by flow cytometry. We also measured proliferative potential and cytokine expression of Ag85A-specific CD4+ T cells. During the effector phase, MVA85A-induced specific CD4+ T cells coexpressed IFN-γ and IL-2, skin homing integrins, and the activation marker CD38. This was followed by contraction and a transition to predominantly IL-2-expressing, CD45RA−CCR7+CD27+ or CD45RA+CCR7+CD27+ specific CD4+ T cells. These surface phenotypes were similar to Ag85A-specific T cells prior to MVA85A. However, functional differences were observed postvaccination: specific proliferative capacity was markedly higher after 6–12 months than before vaccination. Our data suggest that MVA85A vaccination may modulate Ag85A-specific CD4+ T-cell function, resulting in greater recall potential. Importantly, surface phenotypes commonly used as proxies for memory T-cell function did not associate with functional effects of vaccination.
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Research Interests: Clinical Trials, Clinical Trial, Informed Consent, Adolescent, Medicine, and 15 moreSouth Africa, Humans, Child, Clinical research, Research Ethics Committees, Female, Male, Infant, Newborn Infant, Adult, Morbidity, Time Factors, Clinical Trials as Topic, Child preschool, and Medical and Health Sciences
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Background Sensitive point-of-care screening tests are urgently needed to identify individuals at highest risk of tuberculosis. We prospectively tested performance of host-blood transcriptomic tuberculosis signatures. Methods Adults... more
Background Sensitive point-of-care screening tests are urgently needed to identify individuals at highest risk of tuberculosis. We prospectively tested performance of host-blood transcriptomic tuberculosis signatures. Methods Adults without suspicion of tuberculosis were recruited from five endemic South African communities. Eight parsimonious host-blood transcriptomic tuberculosis signatures were measured by microfluidic RT-qPCR at enrolment. Upper respiratory swab specimens were tested with a multiplex bacterial-viral RT-qPCR panel in a subset of participants. Diagnostic and prognostic performance for microbiologically confirmed prevalent and incident pulmonary tuberculosis was tested in all participants at baseline and during active surveillance through 15 months follow-up, respectively. Results Among 20,207 HIV-uninfected and 963 HIV-infected adults screened; 2923 and 861 were enroled. There were 61 HIV-uninfected (weighted prevalence 1.1%) and 10 HIV-infected (prevalence 1.2%) ...
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Rationale: AERAS-402 is a novel TB vaccine designed to boost immunity primed by BCG, the only licensed vaccine. Objectives: We investigated the safety and immunogenicity of AERAS-402 in healthy Mycobacterium tuberculosis uninfected BCG... more
Rationale: AERAS-402 is a novel TB vaccine designed to boost immunity primed by BCG, the only licensed vaccine. Objectives: We investigated the safety and immunogenicity of AERAS-402 in healthy Mycobacterium tuberculosis uninfected BCG vaccinated adults from a TB endemic region of South Africa. Methods: Escalating doses of AERAS-402 vaccine were administered intramuscularly to each of 3 groups of healthy South African BCG vaccinated adults, while a 4 group received 2 injections of the maximum dose. Participants were followed up for 6 months with all adverse effects documented. Vaccine-induced CD4 and CD8 T cell immunity was characterized by an intracellular cytokine staining assay of whole blood and peripheral blood mononuclear cells (PBMCs). Measurements and Main Results: AERAS-402 was well tolerated, and no vaccinerelated serious adverse events were recorded. The vaccine induced a robust CD4 T cell response dominated by cells co-expressing IFN-γ, TNF-α, and IL-2 (“polyfunctional” ...
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Background Tuberculosis (TB) is caused by Mycobacterium tuberculosis (Mtb) infection and is a major public health problem. Clinical challenges include the lack of a blood-based test for active disease. Current blood-based tests, such as... more
Background Tuberculosis (TB) is caused by Mycobacterium tuberculosis (Mtb) infection and is a major public health problem. Clinical challenges include the lack of a blood-based test for active disease. Current blood-based tests, such as QuantiFERON (QFT) do not distinguish active TB disease from asymptomatic Mtb infection. Methods We hypothesized that TruCulture, an immunomonitoring method for whole-blood stimulation, could discriminate active disease from latent Mtb infection (LTBI). We stimulated whole blood from patients with active TB and compared with LTBI donors. Mtb-specific antigens and live bacillus Calmette-Guérin (BCG) were used as stimuli, with direct comparison to QFT. Protein analyses were performed using conventional and digital enzyme-linked immunosorbent assay (ELISA), as well as Luminex. Results TruCulture showed discrimination of active TB cases from LTBI (P < .0001, AUC = .81) compared with QFT (P = .45, AUC = .56), based on an interferon γ (IFNγ) readout afte...
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Background: We tested diagnostic and prognostic performance of a host blood transcriptomic signature of tuberculosis (RISK11) for screening of people living with HIV (PLHIV) in a prospective, community-based cohort. Methods: Ambulant... more
Background: We tested diagnostic and prognostic performance of a host blood transcriptomic signature of tuberculosis (RISK11) for screening of people living with HIV (PLHIV) in a prospective, community-based cohort. Methods: Ambulant adult volunteers living with HIV were enrolled at five South African sites. RISK11 status was assessed at baseline by real-time PCR. Participants and study staff were blinded to the result. Participants underwent active surveillance for microbiologically-confirmed tuberculosis from enrolment through 15 months. The primary outcomes were prevalence and cumulative incidence of two-sputum-sample positive tuberculosis in RISK11+ versus RISK11- participants. Findings: Among 820 participants with valid RISK11 results, eight (1%) tuberculosis cases were identified at baseline. Risk of prevalent tuberculosis was 13·1-fold (95%CI 2·1-81·6) greater in RISK11+ than RISK11- participants, with tuberculosis prevalence of 2·5% and 0·2%, respectively. RISK11 had diagnostic area under the receiver-operating-characteristic curve (AUC) 88·2%; sensitivity 87·5% and specificity 65·8% at the pre-defined threshold (60%).Thereafter, eight tuberculosis cases were identified through median 15 months follow-up. Tuberculosis incidence was 2·5 vs 0·2 per 100 person-years in RISK11+ compared to RISK11- participants with cumulative incidence ratio 16·0 (95%CI 2·0-129·5); AUC 80·0%; sensitivity 88·6% and specificity 68·9%. By comparison, QuantiFERON TB Gold-Plus (QFT) had a cumulative incidence ratio of 2·0 (95%CI 0·5-8·4); AUC 70·8%; sensitivity 62·1% and specificity 56·2%. Interpretation: RISK11 identified prevalent tuberculosis and predicted risk of progression to incident tuberculosis within 15 months in ambulant PLHIV. Performance approached the World Health Organization Target Product Profile benchmarks for screening and prognostic tests for tuberculosis. QFT performance fell short of the prognostic benchmark. Funding Statement: The study was funded by the Bill & Melinda Gates Foundation (BMGF) (OPP1151915) and by the Strategic Health Innovation Partnerships Unit of the South African Medical Research Council with funds received from the South African Department of Science and Technology. The BMGF contributed to the study design. The regulatory sponsor was the University of Cape Town. Declaration of Interests: AP-N, GW, GC, TJS, and MH report grants from the Bill & Melinda Gates Foundation, during the conduct of the study; AP-N and GW report grants from the South African Medical Research Council, during the conduct of the study; GW and TJS report grants from the South African National Research Foundation, during the conduct of the study. In addition, AP-N and TJS have patents of the RISK11 and RISK6 signatures pending; GW has a patent “TB diagnostic markers” (PCT/IB2013/054377) issued and a patent “Method for diagnosing TB” (PCT/IB2017/052142) pending. The remaining authors have no competing interests to declare. Ethics Approval Statement: The study protocol (Supplement) was approved by the Institutional Human Ethics Committees of each participating site. All participants provided written informed consent in their language of choice.
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ObjectivePaediatric laboratory reference intervals used in Africa and Asia may be derived from historical intervals of predominantly Caucasian infants in Europe or North America. These intervals may therefore not be compatible with the... more
ObjectivePaediatric laboratory reference intervals used in Africa and Asia may be derived from historical intervals of predominantly Caucasian infants in Europe or North America. These intervals may therefore not be compatible with the range of normality for developing country populations. We aimed to compare haematology and biochemistry parameters in healthy South African infants with local laboratory reference intervals.MethodsWe compared the baseline haematology and biochemistry results of 634 (316 male and 318 female) HIV‐unexposed infants, aged 3–6 months, living in a rural area of the Western Cape Province, South Africa, against laboratory reference intervals supplied by the South African National Health Laboratory Services (NHLS). We calculated the percentage of observed values out of bound (in terms of lower and upper limits) compared to laboratory reference intervals.ResultsOf the 634 healthy infants screened, 316 (49.84%) were male and 318 (50.16%) female. A majority (91.0...
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Research Interests: Microbiology, Immunology, Immune response, Medical Microbiology, Inflammation, and 15 moreMedicine, South Africa, Tuberculosis, Population, Humans, Infant, Vaccination, Clinical Sciences, T lymphocytes, Great Britain, Immune system, Adult, Myeloid Cells, Gene Expression Regulation, and Tuberculosis vaccines
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RISK11 transcriptomic signature scores for 20,207 volunteers who were screened at five geographically diverse sites across South Africa. Signature scores were computed from QC'ed gene expression measurements performed by microfluidic... more
RISK11 transcriptomic signature scores for 20,207 volunteers who were screened at five geographically diverse sites across South Africa. Signature scores were computed from QC'ed gene expression measurements performed by microfluidic RT-qPCR on mRNA derived from whole blood collected in PAXgene tubes. Participants were randomised into three groups and followed-up for 15 months to evaluate diagnostic and prognostic performance of RISK11 and to evaluate efficacy of high-dose isoniazid and rifapentine for prevention of incident TB.
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Introduction Respiratory pathogens such as influenza viruses may play an influential role in the pathogenesis of TB by negatively affecting immunity against Mycobacterium tuberculosis (MTB) We discovered and validated a transcriptomic... more
Introduction Respiratory pathogens such as influenza viruses may play an influential role in the pathogenesis of TB by negatively affecting immunity against Mycobacterium tuberculosis (MTB) We discovered and validated a transcriptomic signature of risk (SOR), based on mRNA expression of 11 IFN stimulated genes (ISG), which prospectively differentiates between incident TB cases and healthy controls The SOR score is computed from expression abundance of multiple ISG transcript pairs in peripheral blood, whereby each pair functions as a ?vote? for or against TB risk We aimed to identify respiratory pathogens other than MTB that might also associate with this SOR score and test whether the SOR score differentiates between individuals with and without respiratory pathogens Methods We conducted a nested cross-sectional study of the upper respiratory tract microbiome Upon consent, participants were consecutively enrolled into the study and provided one nasopharyngeal, one oropharyngeal and a PAXgene blood sample Host blood SOR scores were computed from Ct values for each of the 11 genes, measured by microfluidic qRT-PCR We used multiplex real-time PCR to detect 33 pathogens including bacteria, viruses and fungi in the nasopharyngeal and oropharyngeal samples Multivariate linear regression was used to identify pathogens associated with, and estimate their effect on, the SOR score Wilcoxon rank sum tests and receiver-operating-characteristic (ROC) curves were used to differentiate participants with and without respiratory pathogens Results 1,000 HIV-negative volunteers aged between 18 and 60 years were enrolled 13 viral and nine bacterial pathogens were detected Overall prevalence of respiratory pathogens was 43%: 4% were viruses only, 35 8% bacteria only, and 3 2% were a combination of viruses and bacteria Influenza C, rhinoviruses, coronavirus OC43, adenoviruses, and mycoplasma pneumoniae were significantly associated (Table 1) with a high SOR score In ROC curve analysis the SOR score differentiated participants as follows;virus vs no-pathogen (area under the curve;AUC) AUC=0 72, 95% CI: 0 63-0 81, virus vs bacteria AUC=0 72, 95% CI: 0 63-0 81, bacteria vs no-pathogen AUC=0 51, 95% CI: 0 48-0 55 (no difference) Participants with either viruses only or both viruses and bacteria had significantly higher (P=0 001) SOR scores (median 47% and 43%, respectively) compared to participants without pathogens (median 14%) or participants with bacteria only (median 13%) Conclusion Participants with upper respiratory tract viral colonization or infection had elevated SOR scores, suggesting induction of interferon signalling Infection or colonization with respiratory viruses is likely to result in false positive results for other transcriptomic signatures of tuberculosis based on ISGs (Table Presented)
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Statistical analysis plan for the MTBVAC 201 clinical trial. A phase Ib, randomised, double-blind, dose-escalation clinical trial of the safety, reactogenicity and immunogenicity of MTBVAC compared to BCG Vaccine SSI, in newborns living... more
Statistical analysis plan for the MTBVAC 201 clinical trial. A phase Ib, randomised, double-blind, dose-escalation clinical trial of the safety, reactogenicity and immunogenicity of MTBVAC compared to BCG Vaccine SSI, in newborns living in a tuberculosis endemic region with a safety arm in adults.
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Recently, two Phase 2B tuberculosis vaccine trials reported positive efficacy results in adolescents and adults. However, experience in vaccinating these age groups is limited. We identified potential implementation strategies for the... more
Recently, two Phase 2B tuberculosis vaccine trials reported positive efficacy results in adolescents and adults. However, experience in vaccinating these age groups is limited. We identified potential implementation strategies for the M72/AS01E vaccination and BCG-revaccination-like candidates and explored their acceptability and feasibility. We conducted in-depth semi-structured interviews among key decision makers to identify implementation strategies and target groups in South Africa, India, and China. Thematic and deductive analysis using a coding framework were used to identify themes across and within settings. In all three countries there was interest in novel TB vaccines, with school-attending adolescents named as a likely target group. In China and India, older people were also identified as a target group. Routine vaccination was preferred in all countries due to stigma and logistical issues with targeted mass campaigns. Perceived benefits for implementation of M72/AS01E w...
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The SARS-CoV-2 Omicron (B.1.1.529) Variant of Concern (VOC) and its sub-lineages (including BA.2, BA.4/5, BA.2.12.1) contain spike mutations that confer high level resistance to neutralizing antibodies. The NVX-CoV2373 vaccine, a protein... more
The SARS-CoV-2 Omicron (B.1.1.529) Variant of Concern (VOC) and its sub-lineages (including BA.2, BA.4/5, BA.2.12.1) contain spike mutations that confer high level resistance to neutralizing antibodies. The NVX-CoV2373 vaccine, a protein nanoparticle vaccine, has value in countries with constrained cold-chain requirements. Here we report neutralizing titers following two or three doses of NVX-CoV2373. We show that after two doses, Omicron sub-lineages BA.1 and BA.4 were resistant to neutralization by 72% (21/29) and 59% (17/29) of samples. However, after a third dose of NVX-CoV2373, we observed high titers against Omicron BA.1 (GMT: 1,197) and BA.4 (GMT: 582), with responses similar in magnitude to those triggered by three doses of an mRNA vaccine. These data are of particular relevance as BA.4 is emerging to become the dominant strain in many locations, and highlight the potential utility of the NVX-CoV2373 vaccine as a booster in resource-limited environments.
Research Interests: Neutralization and Titer
Background COVID-19 vaccine hesitancy has threatened the ability of many countries worldwide to contain the pandemic. Given the severe impact of the pandemic in South Africa and disruptions to the roll-out of the vaccine in early 2021,... more
Background COVID-19 vaccine hesitancy has threatened the ability of many countries worldwide to contain the pandemic. Given the severe impact of the pandemic in South Africa and disruptions to the roll-out of the vaccine in early 2021, slower-than-expected uptake is a pressing public health challenge in the country. We examined longitudinal changes in COVID-19 vaccination intent among South African adults, as well as determinants of intent to receive a vaccine. Methods We used longitudinal data from Wave 4 (February/March 2021) and Wave 5 (April/May 2021) of the National Income Dynamics Study: Coronavirus Rapid Mobile Survey (NIDS-CRAM), a national and broadly representative panel survey of adults in South Africa. We conducted cross-sectional analyses on aggregate and between-group variation in vaccination intent, examined individual-level changes between waves, and modeled demographic predictors of intent. Results We analysed data for 5629 (Wave 4; 48% male, mean age 41.5 years) an...
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<p>Red data points denote measurements from individuals who became infected with <i>M.tb</i> since completion of the original clinical trial. <i>M.tb</i> infection was defined as conversion to a positive... more
<p>Red data points denote measurements from individuals who became infected with <i>M.tb</i> since completion of the original clinical trial. <i>M.tb</i> infection was defined as conversion to a positive IFN-γ ELISpot assay response to ESAT-6/CFP-10. Frequencies of IFN-γ spot forming cells (SFC) detected before vaccination and at the last time point after MVA85A vaccination were compared using the Wilcoxon signed rank test. Blue p-values denote comparison of data from all individuals, while red p-values denote comparison of <i>M.tb</i>-uninfected (negative responders to ESAT-6/CFP-10) individuals only. (<b>A–D</b>) Longitudinal tracking of Ag85A-specific T cell responses in adults (<b>A</b>, n = 17), adolescents (<b>B</b>, n = 9), children (<b>C</b>, n = 15) and infants (<b>D</b>, n = 27), who received 5×10<sup>7</sup> plaque forming units (pfu) of MVA85A. (<b>E</b>) Comparison of Ag85A-specific IFN-γ ELISPOT responses in subjects who were vaccinated more than 3 years ago with different doses of MVA85A as infants, or who received the placebo vaccine, Prevenar (n = 24 for Group 1, n = 27 for Group 2; n = 24 for Group 3 and n = 23 for the placebo Group). The overall effect was calculated using the Kruskal-Wallis test, while responses in each dose group were compared to the placebo group using the Mann-Whitney U test. Median and IQR IFN-γ ELISPOT response values are shown in <b><a href="http://www.plosone.org/article/info:doi/10.1371/journal.pone.0087340#pone.0087340.s004" target="_blank">Table S1</a></b>.</p
Research Interests: Immune response, Clinical Trials, Global Health, Cytokines, Infectious Diseases, and 15 moreBacterial Diseases, Medicine, Vaccine development, Clinical immunology, Tuberculosis, Immunity, Tracking, T cells, Vaccination, Immune system, Subjects, Responses, Humoral Immunity, Immune cells, and Vaccinated
Human breath contains trace amounts of non-volatile organic compounds (NOCs) which might provide non-invasive methods for evaluating individual health. In previous work, we demonstrated that lipids detected in exhaled breath aerosol (EBA)... more
Human breath contains trace amounts of non-volatile organic compounds (NOCs) which might provide non-invasive methods for evaluating individual health. In previous work, we demonstrated that lipids detected in exhaled breath aerosol (EBA) could be used as markers of active tuberculosis (TB). Here, we advanced our analytical platform for characterizing small metabolites and lipids in EBA samples collected from participants enrolled in clinical trials designed to identify molecular signatures of active TB. EBA samples from 26 participants with active TB and 73 healthy participants were processed using a dual-phase extraction method, and metabolites and lipids were identified via mass spectrometry database matching. In total, 13 metabolite and 9 lipid markers were identified with statistically different optimized relative standard deviation values between individuals diagnosed with active TB and the healthy controls. Importantly, EBA lipid profiles can be used to separate the two sampl...
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Objective: Diagnosis of childhood tuberculosis is limited by the paucibacillary respiratory samples obtained from young children with pulmonary disease. We aimed to compare accuracy of the Xpert® MTB/RIF assay, an automated nucleic acid... more
Objective: Diagnosis of childhood tuberculosis is limited by the paucibacillary respiratory samples obtained from young children with pulmonary disease. We aimed to compare accuracy of the Xpert® MTB/RIF assay, an automated nucleic acid amplification test, between induced sputum and gastric lavage samples from young children in a tuberculosis endemic setting. Methods: We analyzed standardized diagnostic data from HIV negative children younger than four years of age who were investigated for tuberculosis disease near Cape Town, South Africa [2009–2012]. Two paired, consecutive induced sputa and early morning gastric lavage samples were obtained from children with suspected tuberculosis. Samples underwent Mycobacterial Growth Indicator Tube [MGIT] culture and Xpert MTB/RIF assay. We compared diagnostic yield across samples using the two-sample test of proportions and McNemar’s χ2 test; and Wilson’s score method to calculate sensitivity and specificity. Results: 1,020 children were evaluated for tuberculosis during 1,214 admission episodes. Not all children had 4 samples collected. 57 of 4,463[1.3%] and 26 of 4,606[0.6%] samples tested positive for Mycobacterium tuberculosis on MGIT culture and Xpert MTB/RIF assay respectively. 27 of 2,198[1.2%] and 40 of 2,183[1.8%] samples tested positive [on either Xpert MTB/RIF assay or MGIT culture] on induced sputum and gastric lavage samples, respectively. 19/1,028[1.8%] and 33/1,017[3.2%] admission episodes yielded a positive MGIT culture or Xpert MTB/RIF assay from induced sputum and gastric lavage, respectively. Sensitivity of Xpert MTB/RIF assay was 8/30[26.7%; 95% CI: 14.2–44.4] for two induced sputum samples and 7/31[22.6%; 11.4–39.8] [p = 0.711] for two gastric lavage samples. Corresponding specificity was 893/893[100%;99.6–100] and 885/890[99.4%;98.7–99.8] respectively [p = 0.025]. Conclusion: Sensitivity of Xpert MTB/RIF assay was low, compared to MGIT culture, but diagnostic performance of Xpert MTB/RIF did not differ sufficiently between induced sputum and gastric lavage to justify selection of one sampling method over the other, in young children with suspected pulmonary TB
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The Validation of Correlates of Risk of TB Disease in High Risk Populations (CORTIS-HR) Study, a companion study of the CORTIS-01 Trial (ClinicalTrials.gov: NCT02735590), was conducted to test the diagnostic and prognostic performance of... more
The Validation of Correlates of Risk of TB Disease in High Risk Populations (CORTIS-HR) Study, a companion study of the CORTIS-01 Trial (ClinicalTrials.gov: NCT02735590), was conducted to test the diagnostic and prognostic performance of the RISK11 biomarker for tuberculosis (TB) disease in people living with HIV (PLHIV) in an ambulant community setting. The “CORTIS-HR pubdata.csv” is a public, subject-level dataset for the CORTIS-HR study containing key variables necessary to reconstruct the study findings. A data dictionary is provided below. The “CORTIS-HR PCR data.csv” provides subject-level TaqMan qPCR probe raw CT (cycle threshold) gene expression data from the Fluidigm microfluidic 96.96 Gene Expression Integrated Fluidic Circuits (chips) with sample quality control (“SAMPLE_QC”) results. Analyses of the qPCR probe data are ongoing; the embargo on this data ends 1 July 2021 when the data will be available on ZivaHub. “CORTIS-HR Protocol Version 1.0.pdf” and “CORTIS-HR SAP Ver...
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We tested performance of host-blood transcriptomic tuberculosis (TB) signatures for active case-finding. Among 20,207 HIV-uninfected and 963 HIV-infected adults screened; 2,923 and 861 were enrolled from five South African communities.... more
We tested performance of host-blood transcriptomic tuberculosis (TB) signatures for active case-finding. Among 20,207 HIV-uninfected and 963 HIV-infected adults screened; 2,923 and 861 were enrolled from five South African communities. Eight signatures were measured by microfluidic RT-qPCR and participants were microbiologically-investigated for pulmonary TB at baseline, and actively surveilled for incident disease through 15 months. Diagnostic AUCs for 61 HIV-uninfected (weighted-prevalence 1.1%) and 10 HIV-infected (prevalence 1.2%) prevalent TB cases for the 8 signatures were 0.63–0.79 and 0.65–0.88, respectively. Thereafter, 24 HIV-uninfected and 9 HIV-infected participants progressed to incident TB (1.1 and 1.0 per 100 person-years, respectively). Prognostic AUCs through 15-months follow-up were 0.49–0.66 and 0.54–0.81, respectively. Prognostic performance for incident TB occurring within 6-12 months in HIV-negative participants was higher for all signatures. None of the signat...
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We characterize the breadth, function and phenotype of innate and adaptive cellular responses in a prevention of Mycobacterium tuberculosis infection trial. Responses are measured by whole blood intracellular cytokine staining at baseline... more
We characterize the breadth, function and phenotype of innate and adaptive cellular responses in a prevention of Mycobacterium tuberculosis infection trial. Responses are measured by whole blood intracellular cytokine staining at baseline and 70 days after vaccination with H4:IC31 (subunit vaccine containing Ag85B and TB10.4), Bacille Calmette-Guerin (BCG, a live attenuated vaccine) or placebo (n = ~30 per group). H4:IC31 vaccination induces Ag85B and TB10.4-specific CD4 T cells, and an unexpected NKTlike subset, that expresses IFN-γ, TNF and/or IL-2. BCG revaccination increases frequencies of CD4 T cell subsets that either express Th1 cytokines or IL-22, and modestly increases IFNγ-producing NK cells. In vitro BCG re-stimulation also triggers responses by donor-unrestricted T cells, which may contribute to host responses against mycobacteria. BCG, which demonstrated efficacy against sustained Mycobacterium tuberculosis infection, modulates multiple immune cell subsets, in particula...