Browsing by Author "Scriba, Thomas J"

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    Characterisation of Mycobacterium tuberculosis specific T cell immunity with HLA class II tetramers
    (2014) Dintwe, One Bridget; Scriba, Thomas J; Nemes, Elisa
    Tuberculosis (TB) remains a global health burden, with an estimated 1.3 million people dying from the disease in 2012. Protective immunity against TB is thought to depend on specific T cells. However, exactly which T cell characteristics are required for immunological protection is unknown. To gain a better understanding of M. tuberculosis (M.tb)-specific memory T cell immunity, we studied longevity and function of M.tb-specific memory T cells. We reasoned that such knowledge would facilitate rational vaccine design of a TB vaccine. We designed and developed a set of new HLA class II tetramers to perform in-depth studies of M.tb-specific CD4 T cell responses. We studied persons vaccinated with a novel TB vaccine, MVA85A, as well as persons naturally infected with M.tb. Antigen-specific CD4 T cells were detected with HLA class II tetramers and functional and phenotypic attributes of these T lymphocytes characterised by standard flow cytometric techniques. Comprehensive transcriptional analyses of M.tb-specific CD4 T cells, which were also sorted by FACS, were performed by microfluidic quantitative real-time PCR. Early after intradermal vaccination with MVA85A a large proportion of Ag85Aspecific CD4 T cells were highly activated, expressed skin homing markers and displayed an effector T cell phenotype. This effector response waned rapidly and gave way to antigen-specific central memory CD4 T cells with high proliferative potential, which we proposed may be desirable for protection. However, recent results from the first efficacy trial of MVA85A in infants suggested that these cells are not sufficient to enhance protection beyond that induced by BCG vaccination at birth. Further, we characterised surface marker expression and transcriptional signatures of a newly detected and described population of M.tb-specific CD4 T cells, that displayed a CD45RA+CCR7+CD27+ naïve-like T cell phenotype. We hypothesised that these unique M.tb-specific naïve-like CD4 T cells had a transcriptional profile distinct from truly naïve, central memory and effector bulk CD4 T cells, as well as other M.tb-specific memory CD4 T cell subsets. Gene expression of CFP10-specific naïve-like CD4 T cells reflected an mRNA profile that was very distinct from truly naïve bulk CD4 T cells. Rather, naïvelike CD4 T cells clustered with bulk effector CD4 T cells in unsupervised analysis methods such as hierarchical clustering and principle component analyses. Further analyses revealed that naïve-like CFP10-specific CD4 cells expressed mRNAs coding for effector cytokines, cytotoxic molecules and chemokine receptors consistent with effector memory T cells. However, the overall transcriptional profile was more similar to CFP10-specific central memory CD4 T cells than that of the effector CD4 T cells. We concluded that M.tb-specific naïve-like CD4 T cells may possess an ability to traffic to sites of infection or inflammation, where they may contribute to effector function. These hypotheses need confirmation on a protein level. The HLA class II tetramers developed in this thesis are valuabe tools for assessing direct ex vivo M.tb-specific CD4 T cell responses without activation and cell perturbation. Our findings contribute to a more comprehensive understanding of T cell immunity induced by vaccines and/or natural M.tb infection.
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    Correlates of risk of TB disease in infants with differential response to BCG vaccination
    (2014) Njikan, Samuel Ayaba; Hanekom, Willem A; Nemes, Elisa; Scriba, Thomas J
    Studying prospective immune correlates of risk of TB disease following BCG vaccination is an important first step towards determining correlates of protection against TB, which can be identified only in a placebo-controlled randomized controlled trial (RCT) of an effective vaccine. To study correlates of risk of TB disease, we collected and stored blood from healthy 10-week old infants vaccinated with BCG at birth. During two years of follow up, infants who developed lung TB were defined as cases, while those who did not develop TB disease were defined as controls. We measured Th1/Th17 cytokine production by BCG-specific T cells, release of pro- and anti-inflammatory mediators, cytotoxic T cell potential and proliferation in response to BCG as potential correlates of risk of TB disease but none of these outcomes were different between cases and controls. However, transcriptional profiling of PBMC revealed two clusters of infants and interestingly, the gene expression profiles from cases and controls in the two clusters were in opposite directions. Based on this, we hypothesised that analysing the two clusters of infants separately will allow discovery of correlates of risk of TB, which were absent when clustering was not taken into account.
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    Determinants of innate immune responses to mycobacteria
    (2012) Shey, Muki Shehu; Hanekom, Willem A; Scriba, Thomas J
    Innate cells such as macrophages, monocytes, myeloid dendritic cells and granulocytes recognise mycobacteria and initiate immune responses such as phagocytosis, cytokine production and expression of maturation markers. The type and magnitude of innate responses to mycobacteria may determine the subsequent adaptive responses generated. Our aims were to determine maturational changes in innate immune responses to mycobacteria over the first 9 months of life, and to assess effects of genetic variations in toll-like receptors on host responses to mycobacteria. This knowledge is important for designing rational strategies for vaccination against tuberculosis.
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    Evaluation of Xpert® MTB/RIF assay in induced sputum and gastric lavage samples from young children with suspected tuberculosis from the MVA85A TB vaccine trial
    (Public Library of Science, 2015) Bunyasi, Erick Wekesa; Tameris, Michele; Geldenhuys, Hennie; Schmidt, Bey-Marrie; Luabeya, Angelique Kany Kany; Mulenga, Humphrey; Scriba, Thomas J; Hanekom, Willem A; Mahomed, Hassan; McShane, Helen
    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 χ 2 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. Trial Registration ClinicalTrials.gov NCT00953927
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    Factors affecting diagnostic and prognostic performance of a transcriptomic signature of risk of tuberculosis in HIV-uninfected South African adults
    (2022) Mulenga, Humphrey; Hatherill, Mark; Scriba, Thomas J
    Background Host blood transcriptomic signatures, such as RISK11, have potential as tests for diagnosing and predicting tuberculosis. This thesis aimed to review the literature, evaluate host and non-host factors associated with variability of the RISK11 signature and impact on discriminatory performance and evaluate RISK11 performance in combination with tests of Mycobacterium tuberculosis sensitization. Methods A systematic review of discriminatory performance of transcriptomic signatures for tuberculosis was conducted. RISK11, QuantiFERON-TB Gold-Plus and host factors were analysed in a prospective cohort, in which a cross-sectional study of upper respiratory organisms was nested. Effects on RISK11 were quantified using multivariable generalised regression. Discriminatory performance of RISK11, and RISK11/QuantiFERON combinations, were quantified by area under the curve and/or sensitivity and specificity. Results In the literature, one signature (90% sensitivity; 74% specificity) met the minimal criteria for a triage test; one signature (86% sensitivity; 84% specificity) met the minimal criteria for a predictive test. In the prospective cohort, RISK11 scores were higher among individuals with prevalent tuberculosis (+18.90%), night sweats (+14.65%) and incident tuberculosis (+7.29%). Cough was associated with 72.55% higher RISK11 score in prevalent tuberculosis cases. Stratification by cough improved diagnostic performance from area under curve of 0.74 overall, to 0.97 in cough-positive participants. Adjustment for host factors affecting controls did not change RISK11 discriminatory performance. In the cross-sectional study, RISK11 scores were higher by +16.7%, +67.8% and +13.5% in participants with coronavirus, influenza and rhinovirus, respectively, such that RISK11 could not differentiate prevalent tuberculosis from upper respiratory viruses. Compared to RISK11, the Either-Positive test combination decreased diagnostic negative likelihood ratio from 0.7 to 0.3, and prognostic negative likelihood ratio from 0.9 to 0.3, but did not improve upon QuantiFERON alone. Compared to QuantiFERON, the Both-Positive test combination increased diagnostic positive likelihood ratio from 1.3 to 4.7, and prognostic positive likelihood ratio from 1.4 to 2.8, but did not improve upon RISK11 alone. Conclusion RISK11 holds promise as a triage test for tuberculosis. Further optimisation, or development of new signatures is needed to improve discrimination of subclinical tuberculosis, without cough, and to mitigate the impact of viral co-infection. RISK11/QuantiFERON combination testing is not recommended.
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    Human myeloid cell and innate lymphocyte responses to mycobacterial vaccination or infection
    (2022) Murphy, Melissa; Nemes, Elisa; Scriba, Thomas J
    We investigated immune responses beyond conventional T cells in the context of BCG vaccination and tuberculosis disease.
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    Human newborn bacille Calmette–Guérin vaccination and risk of tuberculosis disease: a case-control study
    (2016) Fletcher, Helen A; Filali-Mouhim, Ali; Nemes, Elisa; Hawkridge, Anthony; Keyser, Alana; Njikan, Samuel; Hatherill, Mark; Scriba, Thomas J; Abel, Brian; Kagina, Benjamin M; Veldsman, Ashley; Agudelo, Nancy Marín; Kaplan, Gilla; Hussey, Gregory D; Sekaly, Rafick-Pierre; Hanekom, Willem A
    : An incomplete understanding of the immunological mechanisms underlying protection against tuberculosis (TB) hampers the development of new vaccines against TB. We aimed to define host correlates of prospective risk of TB disease following bacille Calmette-Guérin (BCG) vaccination. : In this study, 5,726 infants vaccinated with BCG at birth were enrolled. Host responses in blood collected at 10 weeks of age were compared between infants who developed pulmonary TB disease during 2 years of follow-up (cases) and those who remained healthy (controls). : Comprehensive gene expression and cellular and soluble marker analysis failed to identify a correlate of risk. We showed that distinct host responses after BCG vaccination may be the reason: two major clusters of gene expression, with different myeloid and lymphoid activation and inflammatory patterns, were evident when all infants were examined together. Cases from each cluster demonstrated distinct patterns of gene expression, which were confirmed by cellular assays. : Distinct patterns of host responses to Mycobacterium bovis BCG suggest that novel TB vaccines may also elicit distinct patterns of host responses. This diversity should be considered in future TB vaccine development.
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    Inflammatory and myeloid-associated gene expression before and one day after infant vaccination with MVA85A correlates with induction of a T cell response
    (2014-06-09) Matsumiya, Magali; Harris, Stephanie A; Satti, Iman; Stockdale, Lisa; Tanner, Rachel; O’Shea, Matthew K; Tameris, Michelle; Mahomed, Hassan; Hatherill, Mark; Scriba, Thomas J; Hanekom, Willem A; McShane, Helen; Fletcher, Helen A
    Abstract Background Tuberculosis (TB) remains a global health problem, with vaccination likely to be a necessary part of a successful control strategy. Results of the first Phase 2b efficacy trial of a candidate vaccine, MVA85A, evaluated in BCG-vaccinated infants were published last year. Although no improvement in efficacy above BCG alone was seen, cryopreserved samples from this trial provide an opportunity to study the immune response to vaccination in this population. Methods We investigated blood samples taken before vaccination (baseline) and one and 28 days post-vaccination with MVA85A or placebo (Candin). The IFN-γ ELISpot assay was performed at baseline and on day 28 to quantify the adaptive response to Ag85A peptides. Gene expression analysis was performed at all three timepoints to identify early gene signatures predictive of the magnitude of the subsequent adaptive T cell response using the significance analysis of microarrays (SAM) statistical package and gene set enrichment analysis. Results One day post-MVA85A, there is an induction of inflammatory pathways compared to placebo samples. Modules associated with myeloid cells and inflammation pre- and one day post-MVA85A correlate with a higher IFN-γ ELISpot response post-vaccination. By contrast, previous work done in UK adults shows early inflammation in this population is not associated with a strong T cell response but that induction of regulatory pathways inversely correlates with the magnitude of the T cell response. This may be indicative of important mechanistic differences in how T cell responses develop in these two populations following vaccination with MVA85A. Conclusion The results suggest the capacity of MVA85A to induce a strong innate response is key to the initiation of an adaptive immune response in South African infants but induction of regulatory pathways may be more important in UK adults. Understanding differences in immune response to vaccination between populations is likely to be an important aspect of developing successful vaccines and vaccination strategies. Trial registration ClinicalTrials.gov number NCT00953927
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    A quantitative analysis of complexity of human pathogen-specific CD4 T cell responses in healthy M. tuberculosis infected South Africans
    (Public Library of Science, 2016) Arlehamn, Cecilia S Lindestam; McKinney, Denise M; Carpenter, Chelsea; Paul, Sinu; Rozot, Virginie; Makgotlho, Edward; Gregg, Yolande; Van Rooyen, Michele; Ernst, Joel D; Hatherill, Mark; Hanekom, Willem A; Peters, Bjoern; Scriba, Thomas J; Sette, Alessandro
    Author Summary: Human pathogen-specific immune responses are tremendously complex and the techniques to study them ever expanding. There is an urgent need for a quantitative analysis and better understanding of pathogen-specific immune responses. Mycobacterium tuberculosis (Mtb) is one of the leading causes of mortality due to an infectious agent worldwide. Here, we were able to quantify the Mtb-specific response in healthy individuals with Mtb infection from South Africa. The response is highly diverse and 66 epitopes are required to capture 80% of the total reactivity. Our study also show that the majority of the identified epitopes are restricted by multiple HLA alleles. Thus, technical advances are required to capture and characterize the complete pathogen-specific response. This study demonstrates further that the approach combining identified epitopes into "megapools" allows capturing a large fraction of the total reactivity. This suggests that this technique is generally applicable to the characterization of immunity to other complex pathogens. Together, our data provide for the first time a quantitative analysis of the complex pathogen-specific T cell response and provide a new understanding of human infections in a natural infection setting.
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    Real-time investigation of tuberculosis transmission: developing the Respiratory Aerosol Sampling Chamber (RASC)
    (Public Library of Science, 2016) Wood, Robin; Morrow, Carl; III, Clifton E Barry; Bryden, Wayne A; Call, Charles J; Hickey, Anthony J; Rodes, Charles E; Scriba, Thomas J; Blackburn, Jonathan; Issarow, Chacha; Mulder, Nicola; Woodward, Jeremy; Moosa, Atica; Singh, Vinayak; Mizrahi, Valerie; Warner, Digby F
    Knowledge of the airborne nature of respiratory disease transmission owes much to the pioneering experiments of Wells and Riley over half a century ago. However, the mechanical, physiological, and immunopathological processes which drive the production of infectious aerosols by a diseased host remain poorly understood. Similarly, very little is known about the specific physiological, metabolic and morphological adaptations which enable pathogens such as Mycobacterium tuberculosis ( Mtb ) to exit the infected host, survive exposure to the external environment during airborne carriage, and adopt a form that is able to enter the respiratory tract of a new host, avoiding innate immune and physical defenses to establish a nascent infection. As a first step towards addressing these fundamental knowledge gaps which are central to any efforts to interrupt disease transmission, we developed and characterized a small personal clean room comprising an array of sampling devices which enable isolation and representative sampling of airborne particles and organic matter from tuberculosis (TB) patients. The complete unit, termed the Respiratory Aerosol Sampling Chamber (RASC), is instrumented to provide real-time information about the particulate output of a single patient, and to capture samples via a suite of particulate impingers, impactors and filters. Applying the RASC in a clinical setting, we demonstrate that a combination of molecular and microbiological assays, as well as imaging by fluorescence and scanning electron microscopy, can be applied to investigate the identity, viability, and morphology of isolated aerosolized particles. Importantly, from a preliminary panel of active TB patients, we observed the real-time production of large numbers of airborne particles including Mtb , as confirmed by microbiological culture and polymerase chain reaction (PCR) genotyping. Moreover, direct imaging of captured samples revealed the presence of multiple rod-like Mtb organisms whose physical dimensions suggested the capacity for travel deep into the alveolar spaces of the human lung.
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    St John's Wort (Hypericum perforatum L.) photomedicine: hypericin-photodynamic therapy induces metastatic melanoma cell death
    (Public Library of Science, 2014) Kleemann, Britta; Loos, Benjamin; Scriba, Thomas J; Lang, Dirk; Davids, Lester M
    Hypericin, an extract from St John's Wort ( Hypericum perforatum L. ), is a promising photosensitizer in the context of clinical photodynamic therapy due to its excellent photosensitizing properties and tumoritropic characteristics. Hypericin-PDT induced cytotoxicity elicits tumor cell death by various mechanisms including apoptosis, necrosis and autophagy-related cell death. However, limited reports on the efficacy of this photomedicine for the treatment of melanoma have been published. Melanoma is a highly aggressive tumor due to its metastasizing potential and resistance to conventional cancer therapies. The aim of this study was to investigate the response mechanisms of melanoma cells to hypericin-PDT in an in vitro tissue culture model. Hypericin was taken up by all melanoma cells and partially co-localized to the endoplasmic reticulum, mitochondria, lysosomes and melanosomes, but not the nucleus. Light activation of hypericin induced a rapid, extensive modification of the tubular mitochondrial network into a beaded appearance, loss of structural details of the endoplasmic reticulum and concomitant loss of hypericin co-localization. Surprisingly the opposite was found for lysosomal-related organelles, suggesting that the melanoma cells may be using these intracellular organelles for hypericin-PDT resistance. In line with this speculation we found an increase in cellular granularity, suggesting an increase in pigmentation levels in response to hypericin-PDT. Pigmentation in melanoma is related to a melanocyte-specific organelle, the melanosome, which has recently been implicated in drug trapping, chemotherapy and hypericin-PDT resistance. However, hypericin-PDT was effective in killing both unpigmented (A375 and 501mel) and pigmented (UCT Mel-1) melanoma cells by specific mechanisms involving the externalization of phosphatidylserines, cell shrinkage and loss of cell membrane integrity. In addition, this treatment resulted in extrinsic (A375) and intrinsic (UCT Mel-1) caspase-dependent apoptotic modes of cell death, as well as a caspase-independent apoptotic mode that did not involve apoptosis-inducing factor (501 mel). Further research is needed to shed more light on these mechanisms.
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    Systems analysis of the CD4 T cell response induced by the novel subunit tuberculosis vaccine, H1:IC31
    (2015) Musvosvi, Munyaradzi Nyasha; Scriba, Thomas J; Penn-Nicholson, Adam
    In this study we sought to more comprehensively analyse antigen-specific CD4 T cell responses induced by vaccination and to examine the effects of latent M. tb infection on these responses. We had two broad objectives: Firstly, to determine the effects of latent M. tb infection on epitope recognition by mycobacteria-specific CD4 T cells and to design HLA class II tetramers for detection of these cells. Secondly, to characterise antigen-specific CD4 T cells following vaccination with the novel vaccine candidate, H1:IC31, by measuring transcriptomic, phenotypic and functional attributes, and to determine the effects of latent infection on these responses. Firstly, we found that acquisition of M.tb infection did not alter the breadth and/or pattern of Ag85A/ B CD4 T cell epitopes recognised. We determined the HLA allele restriction of identified epitopes, and designed HLA class II tetramers for detection of Ag85-specific CD4 T cells. These results suggest that latent infection does not alter CD4 T cell epitope breadth within Ag85A/ B elicited by BCG vaccination and/or exposure to environmental mycobacteria. The second finding of this work is that underlying infection drives a more effector-like H1-specific CD4 T response after vaccination. Following vaccination M. tb-infected adolescents had higher frequencies of H1-specific CD4 T cells compared with uninfected adolescents. Additionally, H1-specific CD4 T cells from infected adolescents predominantly displayed a CCR7 - CD45RA - effector memory phenotype, had higher proportions of IFN-γ + TNF-α + IL-2 + cells, and expressed higher levels mRNA transcripts encoding effector molecules such as granzyme K and perforin, compared with uninfected adolescents. By contrast, H1-specific CD4 T cells in uninfected adolescents displayed a less differentiated memory phenotype, and had increased expression of central memory genes, compared to cells from infected adolescents. Thirdly, we found that Ag85B and ESAT-6-specific CD4 T cells exhibited markedly distinct transcriptomic profiles, memory phenotypes and cytokine expression patterns in M.tb infected adolescents. The data suggested that ESAT-6-specific cells preferentially drove the effector-like H1-specific response in M.tb infected adolescents. We conclude that while underlying M.tb infection does not affect the epitopes recognized by mycobacteria-specific CD4 T cells, but may promote and maintain effector memory antigen-specific CD4 T cells endowed with immediate effector function and tissue homing.
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    Transcriptomic signatures of recurrent tuberculosis disease and treatment response in HIV-infected individuals
    (2018) Darboe, Fatoumatta; Scriba, Thomas J; Penn-Nicholson, Adam
    HIV-infected persons are at particularly high risk of tuberculosis (TB) disease, especially in TB endemic countries where M. tuberculosis transmission is common. Although antiretroviral therapy (ART) reduces risk of TB, it does not return to that of HIV-uninfected persons. In addition, a previous history of TB disease significantly increases the risk of recurrent TB disease. Identification of HIV-infected individuals at greatest risk of recurrent TB for highly targeted therapy before disease manifestation would be a major advance in the fight against TB. This would also allow the provision of TB treatment in persons with subclinical TB. Diagnosis of TB in HIV-infected persons is markedly undermined by the paucibacillary nature of HIV-associated disease. A non-sputum based diagnostic test that is highly sensitive and specific, such as a blood-based RNA signature, would be an important new tool. Such a test may also facilitate monitoring of TB treatment, opening the possibility for customizing the duration of TB treatment to that necessary for cure. We previously discovered and validated a 16-gene transcriptomic signature with promising prognostic and diagnostic utility for TB in HIV-uninfected persons. The transcriptomic signature could predict progression to active TB disease up to a year before diagnosis and was shown to be a useful tool for TB treatment response monitoring in a treatment cohort of HIV-uninfected persons. The signature was reduced to an 11-gene signature to improve throughput with equivalent prognostic and diagnostic performance. In addition, we developed a smaller, 6-gene signature in preparation for translation to point-of-care testing. In this thesis, we aimed to determine (1) the diagnostic performance of these two transcriptomic signatures in HIV-infected persons, (2) whether they could predict recurrent TB disease in HIV infected persons, and (3) their utility to monitor TB treatment response in HIV infected persons. To assess aim 1, we designed a cross-sectional study of HIV-infected (n=40) and uninfected persons (n=60), each comprising equal numbers of active TB cases and QuantiFERON-positive controls. To assess aims 2 and 3, we designed retrospective substudies among participants enrolled into two clinical studies previously completed by our collaborators at CAPRISA, namely the TRuTH and IMPRESS studies. In the TRuTH cohort participants who developed recurrent TB diagnosis, diagnosed by microbiological testing of induced sputum, were assigned as progressors (n=43), while those who remained asymptomatic were assigned as non-progressors (n=86). In the IMPRESS cohort, participants with a new diagnosis of recurrent TB who initiated TB treatment were stratified into early (n=44) and late (n=19) converters based on time to sputum culture conversion from diagnosis. RNA was isolated from cryopreserved PBMC or PAXgene whole blood and gene expression measured by microfluidic qRT-PCR. Signature scores were generated using in-house customised scripts in R and performance of the signatures was measured using receiver operating characteristic area under the curve (ROC AUC), calculated using the pROC and verification packages in R. The 11-gene and 6-gene signatures could diagnose active TB disease in HIV infected persons with good accuracy (AUC = 0.83 and 0.92, respectively), although performances were lower than those observed in HIV-uninfected persons (AUC = 0.97 and 0.96). Signature performance was decreased in HIV-infected persons due to higher signature scores, reflecting high expression of IFN-stimulated genes, especially in HIV-infected controls. In the TRuTH cohort, these signatures could identify those with recurrent TB within 3 months of diagnosis (AUC = 0.77, p = 0.003), suggesting detection of subclinical disease. Scores of both signatures decreased during TB treatment in the IMPRESS cohort, in participants with early or late sputum conversion. Importantly, two months after initiating TB treatment, the ACS 11-gene signature could differentiate early from late converters. Detectable plasma viral load was associated with higher signature scores in both cohorts, leading to a decrease in signature specificities. We show that the 11-gene and 6-gene signatures performed well as blood-based diagnostic tests for active TB disease in HIV-infected persons. The signatures could detect recurrent TB disease during the subclinical phase of disease progression and demonstrated promise as treatment response markers in HIV-infected persons. The signatures performed best in persons with effectively suppressed HIV load, highlighting the importance of ART adherence and integration of HIV and TB care for effective clinical management of TB.