Browsing by Author "Wilkinson, Katalin A"
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- ItemOpen AccessAltered ratio of IFN-γ/IL-10 in patients with drug resistant Mycobacterium tuberculosis and HIV-tuberculosis immune reconstitution inflammatory syndrome(Public Library of Science, 2012) Skolimowska, Keira H; Rangaka, Molebogeng X; Meintjes, Graeme; Pepper, Dominique J; Seldon, Ronnett; Matthews, Kerryn; Wilkinson, Robert J; Wilkinson, Katalin AWe have described a clinical relationship between HIV-Tuberculosis Immune Reconstitution Inflammatory Syndrome (TB-IRIS) and anti-tubercular drug resistance. Here we studied the immune response of TB-IRIS patients from whom a drug-resistant (n = 11) or drug-susceptible (n = 25) Mycobacterium tuberculosis (MTB) strain was isolated after presenting with TB-IRIS. ELISpot analysis and multiplex cytokine analysis of the supernatant collected from peripheral blood mononuclear cells stimulated overnight with the heat-killed H37Rv MTB laboratory strain was used. Although there was no statistical difference in IFN-gamma ELISpot responses between the two groups, the results point towards higher bacterial load in the drug-resistant patients, possibly due to failed therapy. The ratio between secreted IFN-gamma/IL-10 and IL-2/IL-10 was significantly lower in TB-IRIS patients in whom the cause of TB was a drug-resistant strain compared to those with a fully sensitive strain (p = 0.02). Since host immune responses are dependent on the bacterial load, we hypothesise that the impaired cytokine balance is likely to be caused by the poorly controlled bacterial growth in these patients.
- ItemOpen AccessConserved immune recognition hierarchy of mycobacterial PE/PPE proteins during infection in natural hosts(Public Library of Science, 2012) Vordermeier, H Martin; Hewinson, R Glyn; Wilkinson, Robert J; Wilkinson, Katalin A; Gideon, Hannah P; Young, Douglas B; Sampson, Samantha LThe Mycobacterium tuberculosis genome contains two large gene families encoding proteins of unknown function, characterized by conserved N-terminal proline and glutamate (PE and PPE) motifs. The presence of a large number of PE/PPE proteins with repetitive domains and evidence of strain variation has given rise to the suggestion that these proteins may play a role in immune evasion via antigenic variation, while emerging data suggests that some family members may play important roles in mycobacterial pathogenesis. In this study, we examined cellular immune responses to a panel of 36 PE/PPE proteins during human and bovine infection. We observed a distinct hierarchy of immune recognition, reflected both in the repertoire of PE/PPE peptide recognition in individual cows and humans and in the magnitude of IFN-γ responses elicited by stimulation of sensitized host cells. The pattern of immunodominance was strikingly similar between cattle that had been experimentally infected with Mycobacterium bovis and humans naturally infected with clinical isolates of M. tuberculosis. The same pattern was maintained as disease progressed throughout a four-month course of infection in cattle, and between humans with latent as well as active tuberculosis. Detailed analysis of PE/PPE responses at the peptide level suggests that antigenic cross-reactivity amongst related family members is a major determinant in the observed differences in immune hierarchy. Taken together, these results demonstrate that a subset of PE/PPE proteins are major targets of the cellular immune response to tuberculosis, and are recognized at multiple stages of infection and in different disease states. Thus this work identifies a number of novel antigens that could find application in vaccine development, and provides new insights into PE/PPE biology.
- ItemOpen AccessDetectable changes in the blood transcriptome are present after two weeks of antituberculosis therapy(Public Library of Science, 2012) Bloom, Chloe I; Graham, Christine M; Berry, Matthew P R; Wilkinson, Katalin A; Oni, Tolu; Rozakeas, Fotini; Xu, Zhaohui; Rossello-Urgell, Jose; Chaussabel, Damien; Banchereau, JacquesRationale: Globally there are approximately 9 million new active tuberculosis cases and 1.4 million deaths annually . Effective antituberculosis treatment monitoring is difficult as there are no existing biomarkers of poor adherence or inadequate treatment earlier than 2 months after treatment initiation. Inadequate treatment leads to worsening disease, disease transmission and drug resistance. Objectives To determine if blood transcriptional signatures change in response to antituberculosis treatment and could act as early biomarkers of a successful response. METHODS: Blood transcriptional profiles of untreated active tuberculosis patients in South Africa were analysed before, during (2 weeks and 2 months), at the end of (6 months) and after (12 months) antituberculosis treatment, and compared to individuals with latent tuberculosis. An active-tuberculosis transcriptional signature and a specific treatment-response transcriptional signature were derived. The specific treatment response transcriptional signature was tested in two independent cohorts. Two quantitative scoring algorithms were applied to measure the changes in the transcriptional response. The most significantly represented pathways were determined using Ingenuity Pathway Analysis. RESULTS: An active tuberculosis 664-transcript signature and a treatment specific 320-transcript signature significantly diminished after 2 weeks of treatment in all cohorts, and continued to diminish until 6 months. The transcriptional response to treatment could be individually measured in each patient. CONCLUSIONS: Significant changes in the transcriptional signatures measured by blood tests were readily detectable just 2 weeks after treatment initiation. These findings suggest that blood transcriptional signatures could be used as early surrogate biomarkers of successful treatment response.
- ItemOpen AccessImmune responses to the enduring hypoxic response antigen Rv0188 are preferentially detected in Mycobacterium bovis infected cattle with low pathology(Public Library of Science, 2011) Jones, Gareth J; Pirson, Chris; Gideon, Hannah P; Wilkinson, Katalin A; Sherman, David R; Wilkinson, Robert J; Hewinson, R Glyn; Vordermeier, H MartinThe DosR regulon and the Enduring Hypoxic Response (EHR) define a group of M. tuberculosis genes that are specifically induced in bacilli exposed in vitro to conditions thought to mimic the environment encountered by Mycobacteria during latent infection. Although well described in humans, latent mycobacterial infection in cattle remains poorly understood. Thus, the aim of this study was to identify antigens that may potentially disclose cattle with latent M. bovis infection. To this end, we initially screened 57 pools of overlapping peptides representing 4 DosR regulon and 29 EHR antigens for their ability to stimulate an immune response in whole blood from TB-reactor cattle using IFN-γ and IL-2 as readouts. All 4 DosR regulon proteins were poorly recognized (maximum responder frequency of 10%). For the EHR antigens, both IFN-γ and IL-2 revealed similar response hierarchies, with responder frequencies ranging from 54% down to 3% depending on the given EHR antigen. Furthermore, these results demonstrated that responses in the infected cattle were largely IFN-γ biased. To support the concept for their role in latency, we evaluated if EHR antigen responses were associated with lower pathology. The EHR antigen Rv0188 was recognised predominantly in animals presenting with low pathology scores, whereas responses to ESAT-6/CFP-10 or the other EHR antigens tested were prevalent across the pathology spectrum. However, when we determined the production of additional cytokines induced by the M. bovis antigens PPD-B or ESAT-6/CFP-10, we detected significantly greater PPD-B-induced production of the pro-inflammatory cytokine IL-1β in animals recognizing Rv0188 (i.e. those with limited or no pathology). Thus, these results are consistent with the idea that responses to Rv0188 may identify a subset of animals at early stages of infection or in which disease progression may be limited.
- ItemOpen AccessImmunological markers of protective immune reconstitution in HIV infected persons sensitised by Mycobacterium tuberculosis(2018) Jhilmeet, Nishtha; Wilkinson, Katalin A; Wilkinson, Robert JTuberculosis (TB) is the leading cause of death from a single infectious agent worldwide and HIV-1 co-infection is the leading cause of susceptibility to tuberculosis. Sub-Saharan Africa has a high incidence of TB-HIV-1 coinfection and the risk of TB in HIV-1 infected people is increased at all stages of the infection. Antiretroviral treatment (ART) is the most effective way to reduce the risk of TB in HIV-1 co-infected people. By studying the protective, ART induced immune reconstitution in HIV infected individuals sensitised by Mycobacterium tuberculosis (Mtb), we can identify correlates of protection against tuberculosis in the form of transcriptomic, soluble or cellular biomarkers. This thesis focuses on characterising Mtb-specific reconstituting CD4 T cells as well as soluble and transcriptomic markers in HIV infected persons, sensitised by Mtb, by analysing samples collected longitudinally during 6 months of ART. Analysis of peripheral blood mononuclear cells by 14-colour flow cytometry revealed the proportion and numbers of central memory CD4+ T cells significantly expanded in HIV infected persons on ART, while the proportion and numbers of effector memory and terminally differentiated effector CD4+ T cells decreased significantly. Additionally we noted a significant decrease in the proportion of activated CD4+ T cells, and IL-2 single producing CD4+ T cells in HIV infected persons at 6 months of ART, while polyfunctional Mtb specific CD4+ T cells secreting IFN-γ, IL-2 and TNF-α simultaneously, proportionally increased. Analysis of soluble markers in the plasma of HIV infected persons revealed an overall decrease in pro-inflammatory cytokines during 6 months of ART. A significant decrease in IFN-γ, IL-1α, IL-1β, IL-6, IL-17A and TNF-α was observed, and concentrations of these cytokines fell towards those observed in HIV uninfected persons. Transcriptomic analyses of 30 genes normalized to 3 different housekeeping genes, showed an overall increase in the expression of T cell memory specific genes, illustrating the regeneration of the memory T cell pool in HIV infected adults on ART. Larger number of central memory specific genes showed increased expression when normalised to at least two housekeeping genes, as compared to effector memory specific genes. These results support the reconstitution of central memory CD4 T-cell specific response at 6 months of ART. Our data provides insight into the reconstituting immune response to latent TB infection in the context of HIV infection and identifies potential correlates of decreased susceptibility to TB. We also show decreasing soluble and cellular factors indicative of decreasing immune activation in HIV infected persons receiving ART.
- ItemOpen AccessImpairment of IFN-gamma response to synthetic peptides of mycobacterium tuberculosis in a 7-day whole blood assay(Public Library of Science, 2013) Gideon, Hannah Priyadarshini; Hamilton, Melissa Shea; Wood, Kathryn; Pepper, Dominique; Oni, Tolu; Seldon, Ronnett; Banwell, Claire; Langford, Paul R; Wilkinson, Robert J; Wilkinson, Katalin AStudies on Mycobacterium tuberculosis (MTB) antigens are of interest in order to improve vaccine efficacy and to define biomarkers for diagnosis and treatment monitoring. The methodologies used for these investigations differ greatly between laboratories and discordant results are common. The IFN-gamma response to two well characterized MTB antigens ESAT-6 and CFP-10, in the form of recombinant proteins and synthetic peptides, was evaluated in HIV-1 uninfected persons in both long-term (7 day) and 24 hour, commercially available QuantiFERON TB Gold in Tube (QFT-GIT), whole blood assays. Our findings showed differences in the IFN-gamma response between 24 hour and 7 day cultures, with recombinant proteins inducing a significantly higher response than the peptide pools in 7 day whole blood assays. The activity of peptides and recombinant proteins did not differ in 24 hour whole blood or peripheral blood mononuclear cell (PBMC) based assays, nor in the ELISpot assay. Further analysis by SELDI-TOF mass spectrometry showed that the peptides are degraded over the course of 7 days of incubation in whole blood whilst the recombinant proteins remain intact. This study therefore demonstrates that screening antigenic candidates as synthetic peptides in long-term whole blood assays may underestimate immunogenicity.
- ItemOpen AccessModern lineages of Mycobacterium tuberculosis exhibit lineage-specific patterns of growth and cytokine induction in human monocyte-derived macrophages(Public Library of Science, 2012) Sarkar, Rajesh; Lenders, Laura; Wilkinson, Katalin A; Wilkinson, Robert J; Nicol, Mark PBACKGROUND: Strains of Mycobacterium tuberculosis vary in virulence. Strains that have caused outbreaks in the United States and United Kingdom have been shown to subvert the innate immune response as a potential immune evasion mechanism. There is, however, little information available as to whether these patterns of immune subversion are features of individual strains or characteristic of broad clonal lineages of M. tuberculosis . METHODS: Strains from two major modern lineages (lineage 2 [East-Asian] and lineage 4 [Euro-American]) circulating in the Western Cape in South Africa as well as a comparator modern lineage (lineage 3 [CAS/Delhi]) were identified. We assessed two virulence associated characteristics: mycobacterial growth (in liquid broth and monocyte derived macrophages) and early pro-inflammatory cytokine induction. RESULTS: In liquid culture, Lineage 4 strains grew more rapidly and reached higher plateau levels than other strains (lineage 4 vs. lineage 2 p = 0.0024; lineage 4 vs. lineage 3 p = 0.0005). Lineage 3 strains were characterized by low and early plateau levels, while lineage 2 strains showed an intermediate growth phenotype. In monocyte-derived macrophages, lineage 2 strains grew faster than lineage 3 strains (p<0.01) with lineage 4 strains having an intermediate phenotype. Lineage 2 strains induced the lowest levels of pro-inflammatory TNF and IL-12p40 as compared to other lineages (lineage 2: median TNF 362 pg/ml, IL-12p40 91 pg/ml; lineage 3: median TNF 1818 pg/ml, IL-12p40 123 pg/ml; lineage 4: median TNF 1207 pg/ml, IL-12p40 205 pg/ml;). In contrast, lineage 4 strains induced high levels of IL-12p40 and intermediate level of TNF. Lineage 3 strains induced high levels of TNF and intermediate levels of IL-12p40. CONCLUSIONS: Strains of M. tuberculosis from the three major modern strain lineages possess distinct patterns of growth and cytokine induction. Rapid growth and immune subversion may be key characteristics to the success of these strains in different human populations.
- ItemOpen AccessPlasma cytokine profiles in HIV-1 infected patients developing neuropathic symptoms shortly after commencing antiretroviral therapy: a case-control study(2014-02-10) Van der Watt, Johan J; Wilkinson, Katalin A; Wilkinson, Robert J; Heckmann, Jeannine MAbstract Background In patients infected with human immunodeficiency virus 1 (HIV-1) neuropathic symptoms may develop within weeks of starting combination antiretroviral therapy (cART). This timing coincides with the occurrence of immune reconstitution inflammatory syndrome. Our objective was to investigate the longitudinal association of plasma cytokine and soluble receptor concentrations with incident neuropathic symptoms within 12 weeks of starting programme-based cART in a nested case-control study. Methods One hundred and twenty adults without neuropathic symptoms and about to initiate cART were followed longitudinally for 24 weeks after cART initiation. Subjects were examined for peripheral neuropathy at baseline (pre-cART) and 2-, 4-, 12- and 24 weeks thereafter. Individuals developing neuropathic symptoms within 12 weeks of starting cART were matched in a nested case-control design with those remaining symptom-free for at least 24 weeks. Plasma was collected at each visit. Cytokines and soluble receptors were quantified using multiplex immunometric assays. Results Incident neuropathic symptoms occurred in 32 (27%) individuals within 12 weeks of starting cART for the first time. Cytokine concentrations increased at 2 weeks, irrespective of symptom-status, returning to baseline concentrations at 12 weeks. Compared to the control group, the symptomatic group had higher baseline levels of interleukin-1 receptor (IL-1R)-antagonist. The symptomatic group also showed greater increases in soluble interleukin-2 receptor-alpha and tumour necrosis factor (TNF) receptor-II levels at week 2 and soluble interleukin-6 receptor levels at week 12. Ratios of pro-inflammatory- vs anti-inflammatory cytokines were higher for TNF-alpha/IL-4 (p = 0.022) and interferon-gamma/IL-10 (p = 0.044) in those developing symptoms. After 24 weeks of cART, the symptomatic group showed higher CD4+ counts (p = 0.002). Conclusions The initiation of cART in previously treatment naïve individuals was associated with a cytokine 'burst’ between 2- and 4 weeks compared with pre-cART levels. Individuals developing neuropathic symptoms within 12 weeks of starting cART showed evidence of altered cytokine concentrations even prior to initiating cART, most notably higher circulating IL-1R-antagonist levels, and altered ratios of “pain-associated” cytokine and soluble receptors shortly after cART initiation.
- ItemOpen AccessPrevalence, hemodynamics, and cytokine profile of effusive-constrictive pericarditis in patients with tuberculous pericardial effusion(Public Library of Science, 2013) Ntsekhe, Mpiko; Matthews, Kerryn; Syed, Faisal F; Deffur, Armin; Badri, Motasim; Commerford, Patrick J; Gersh, Bernard J; Wilkinson, Katalin A; Wilkinson, Robert J; Mayosi, Bongani MBACKGROUND: Effusive constrictive pericarditis (ECP) is visceral constriction in conjunction with compressive pericardial effusion. The prevalence of proven tuberculous ECP is unknown. Whilst ECP is distinguished from effusive disease on hemodynamic grounds, it is unknown whether effusive-constrictive physiology has a distinct cytokine profile. We conducted a prospective study of prevalence and cytokine profile of effusive-constrictive disease in patients with tuberculous pericardial effusion. METHODS: From July 2006 through July 2009, the prevalence of ECP and serum and pericardial levels of inflammatory cytokines were determined in adults with tuberculous pericardial effusion. The diagnosis of ECP was made by combined pericardiocentesis and cardiac catheterization. RESULTS: Of 91 patients evaluated, 68 had tuberculous pericarditis. The 36/68 patients (52.9%; 95% confidence interval [CI]: 41.2-65.4) with ECP were younger (29 versus 37 years, P=0.02), had a higher pre-pericardiocentesis right atrial pressure (17.0 versus 10.0 mmHg, P<0.0001), serum concentration of interleukin-10 (IL-10) (38.5 versus 0.2 pg/ml, P<0.001) and transforming growth factor-beta (121.5 versus 29.1 pg/ml, P=0.02), pericardial concentration of IL-10 (84.7 versus 20.4 pg/ml, P=0.006) and interferon-gamma (2,568.0 versus 906.6 pg/ml, P=0.03) than effusive non-constrictive cases. In multivariable regression analysis, right atrial pressure > 15 mmHg (odds ratio [OR] = 48, 95%CI: 8.7-265; P<0.0001) and IL-10 > 200 pg/ml (OR=10, 95%CI: 1.1, 93; P=0.04) were independently associated with ECP. CONCLUSION: Effusive-constrictive disease occurs in half of cases of tuberculous pericardial effusion, and is characterized by greater elevation in the pre-pericardiocentesis right atrial pressure and pericardial and serum IL-10 levels compared to patients with effusive non-constrictive tuberculous pericarditis.
- ItemOpen AccessQuantiFERON conversion following tuberculin administration is common in HIV infection and relates to baseline response(BioMed Central, 2016-10-07) Esmail, Hanif; Thienemann, Friedrich; Oni, Tolu; Goliath, Rene; Wilkinson, Katalin A; Wilkinson, Robert JBackground: HIV-1 infection impairs tuberculosis (TB) specific immune responses affecting the diagnosis of latent TB. We aimed to (1) determine the proportion of HIV-1-infected adults with a negative QuantiFERON®-TB Gold in-tube (QFT-GIT) and Tuberculin skin testing (TST) that convert to QFT-GIT positive following TST, and (2) evaluate the relationship between conversion and baseline QFT-GIT results. Methods: HIV-1 infected adults being screened for a TB vaccine study in South Africa underwent QFT-GIT followed by TST. As per protocol, QFT-GIT was repeated if randomization was delayed allowing for evaluation of TST boosting in a proportion of participants. Results: Of the 22 HIV-1 infected, TST and QFT-GIT negative adults (median CD4 477/mm3 IQR 439–621) who had QFT-GIT repeated after median 62 days (IQR 49–70), 40.9 % (95 % CI 18.6–63.2 %) converted. Converters had a significantly greater increase in the background subtracted TB antigen response (TBAg-Nil – all units IU/mL) following TST, 0.82 (IQR 0.39–1.28) vs 0.03 (IQR −0.05–0.06), p = 0.0001. Those who converted also had a significantly higher baseline TBAg-Nil 0.21(IQR 0.17–0.26) vs 0.02(IQR 0.01–0.07), p = 0.002. Converters did not differ with regard to CD4 count or ART status. ROC analysis showed a baseline cut off of 0.15 correctly classified 86.4 % of converters with 88.9 % sensitivity. Conclusions: Our findings support the possibility that there are 2 distinct groups in an HIV-1 infected population with negative QFT-GIT and TST; a true negative group and a group showing evidence of a weak Mtb specific immune response that boosts significantly following TST resulting in conversion of the test result that may represent false negatives. Further evaluation of whether a lower cut off may improve sensitivity of QFT-GIT in this population is warranted.
- ItemOpen AccessA Recent HIV Diagnosis Is Associated with Non-Completion of Isoniazid Preventive Therapy in an HIV-Infected Cohort in Cape Town(Public Library of Science, 2012) Oni, Tolu; Tsekela, Relebohile; Kwaza, Bekekile; Manjezi, Lulama; Bangani, Nonzwakazi; Wilkinson, Katalin A; Coetzee, David; Wilkinson, Robert JIntroduction: Despite high rates of successful treatment TB incidence in South Africa remains high, suggesting ongoing transmission and a large reservoir of latently infected persons. Isoniazid preventive therapy (IPT) is recommended as preventive therapy in HIV-infected persons. However, implementation has been slow, impeded by barriers and challenges including the fear of non-adherence. Objective and Methods: The aim was to evaluate predictors of IPT non-completion. One hundred and sixty four antiretroviral therapy (ART)-naïve HIV-infected patients with tuberculin skin test ≥5 mm were recruited from Khayelitsha day hospital and followed up monthly. A questionnaire was used to collect demographic information. Results: The overall completion rate was 69%. In multivariable analysis, there was a 29% decrease in risk of non-completion for every year after HIV diagnosis (OR 0.81; 95% C.I. 0.68–0.98). Self-reported alcohol drinkers (OR 4.05; 95% C.I. 1.89–9.06) also had a four-fold higher risk of non-completion, with a strong association between alcohol drinkers and smoking (χ2 27.08; p<0.001). Conclusion: We identify patients with a recent HIV diagnosis, in addition to self-reported drinkers and smokers as being at higher risk of non-completion of IPT. The period of time since HIV diagnosis should therefore be taken into account when initiating IPT. Our results also suggest that smokers and alcohol drinkers should be identified and targeted for adherence interventions when implementing IPT on a wider scale.
- ItemOpen AccessSmoking, BCG and employment and the risk of tuberculosis infection in HIV-infected persons in South Africa(Public Library of Science, 2012) Oni, Tolu; Gideon, Hannah P; Bangani, Nonzwakazi; Tsekela, Relebohile; Seldon, Ronnett; Wood, Kathryn; Wilkinson, Katalin A; Goliath, Rene T; Ottenhoff, Tom H M; Wilkinson, Robert JBACKGROUND: The increased susceptibility to latent tuberculosis infection (LTBI) of HIV-1-infected persons represents a challenge in TB epidemic control. However few studies have evaluated LTBI predictors in a generalized HIV/TB epidemic setting. METHODS: The study recruited 335 HIV-infected participants from Khayelitsha, Cape Town between February 2008 and November 2010. Tuberculin skin tests and interferon-gamma release assays were performed on all participants and active TB excluded using a symptom screen, TB microscopy and culture. RESULTS: LTBI prevalence was 52.7% and 61.2% (TST and IGRA respectively). Being a recent TB contact (OR 2.07; 95% C.I. 1.15-3.69) was associated with TST positivity. Participants with a CD4>200 had a two-fold higher risk of IGRA positivity compared to those with CD4 counts <200 (OR 2.07; 95% C.I. 0.99-4.34). There was also a 19% increase in IGRA positivity risk for every additional year of schooling and a strong association between years of schooling and employment (p = 0.0004). A decreased risk of IGRA positivity was observed in persons with a BCG scar (OR 0.46; 95% C.I. 0.31-0.69) and in smokers (OR 0.47; 95% C.I. 0.23-0.96). CONCLUSION: We report the novel findings of a decreased risk of IGRA positivity in HIV-infected smokers possibly due to decreased interferon production, and in the persons with a BCG scar suggesting a protective role for BCG in this population. We also found an increased risk of TST positivity in employed persons, possibly due to ongoing transmission in public modes of transport.
- ItemOpen AccessTranscriptional Blood Signatures Distinguish Pulmonary Tuberculosis, Pulmonary Sarcoidosis, Pneumonias and Lung Cancers(Public Library of Science, 2013) Bloom, Chloe I; Graham, Christine M; Berry, Matthew P R; Rozakeas, Fotini; Redford, Paul S; Wang, Yuanyuan; Xu, Zhaohui; Wilkinson, Katalin A; Wilkinson, Robert J; Kendrick, YvonneRationale: New approaches to define factors underlying the immunopathogenesis of pulmonary diseases including sarcoidosis and tuberculosis are needed to develop new treatments and biomarkers. Comparing the blood transcriptional response of tuberculosis to other similar pulmonary diseases will advance knowledge of disease pathways and help distinguish diseases with similar clinical presentations. Objectives: To determine the factors underlying the immunopathogenesis of the granulomatous diseases, sarcoidosis and tuberculosis, by comparing the blood transcriptional responses in these and other pulmonary diseases. Methods: We compared whole blood genome-wide transcriptional profiles in pulmonary sarcoidosis, pulmonary tuberculosis, to community acquired pneumonia and primary lung cancer and healthy controls, before and after treatment, and in purified leucocyte populations. Measurements and Main Results: An Interferon-inducible neutrophil-driven blood transcriptional signature was present in both sarcoidosis and tuberculosis, with a higher abundance and expression in tuberculosis. Heterogeneity of the sarcoidosis signature correlated significantly with disease activity. Transcriptional profiles in pneumonia and lung cancer revealed an over-abundance of inflammatory transcripts. After successful treatment the transcriptional activity in tuberculosis and pneumonia patients was significantly reduced. However the glucocorticoid-responsive sarcoidosis patients showed a significant increase in transcriptional activity. 144-blood transcripts were able to distinguish tuberculosis from other lung diseases and controls. Conclusions: Tuberculosis and sarcoidosis revealed similar blood transcriptional profiles, dominated by interferon-inducible transcripts, while pneumonia and lung cancer showed distinct signatures, dominated by inflammatory genes. There were also significant differences between tuberculosis and sarcoidosis in the degree of their transcriptional activity, the heterogeneity of their profiles and their transcriptional response to treatment.