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Ari MM, Beig M, Sholeh M, Khoshmirsafa M. The BCG vaccine, advantages, and disadvantages of introducing new generation vaccines against Mycobacterium tuberculosis. Clin Exp Vaccine Res 2024; 13:184-201. [PMID: 39144128 PMCID: PMC11319110 DOI: 10.7774/cevr.2024.13.3.184] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/29/2023] [Revised: 03/22/2024] [Accepted: 03/29/2024] [Indexed: 08/16/2024] Open
Abstract
Tuberculosis (TB) is consistently ranked among the deadliest diseases worldwide, causing millions of deaths annually. Mycobacterium tuberculosis is the causative agent for this infection. Different antibiotics and vaccines have been discussed as potential treatments and prevention. Currently, there is only one licensed vaccine against TB, Bacillus Calmette-Guérin (BCG). Despite its protective efficacy against TB in children, BCG has failed to protect adults against pulmonary TB, lacks therapeutic value, and can cause complications in immunocompromised individuals. In this review, BCG, the most widely administered vaccine, is discussed, and the newest vaccines available in medicine are discussed. Based on the restrictions that prevent optimal BCG efficacy and the vaccines that are now being tested in various clinical studies, some criteria need to be considered in designing future vaccines.
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Affiliation(s)
- Marzie Mahdizade Ari
- Department of Microbiology, School of Medicine, Iran University of Medical Sciences, Tehran, Iran
| | - Masoumeh Beig
- Department of Bacteriology, Pasteur Institute of Iran, Tehran, Iran
| | - Mohammad Sholeh
- Department of Bacteriology, Pasteur Institute of Iran, Tehran, Iran
| | - Majid Khoshmirsafa
- Department of Microbiology, School of Medicine, Iran University of Medical Sciences, Tehran, Iran
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2
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Lyu M, Lai H, Wang Y, Zhou Y, Chen Y, Wu D, Chen J, Ying B. Roles of alternative splicing in infectious diseases: from hosts, pathogens to their interactions. Chin Med J (Engl) 2023; 136:767-779. [PMID: 36893312 PMCID: PMC10150853 DOI: 10.1097/cm9.0000000000002621] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/09/2022] [Indexed: 03/11/2023] Open
Abstract
ABSTRACT Alternative splicing (AS) is an evolutionarily conserved mechanism that removes introns and ligates exons to generate mature messenger RNAs (mRNAs), extremely improving the richness of transcriptome and proteome. Both mammal hosts and pathogens require AS to maintain their life activities, and inherent physiological heterogeneity between mammals and pathogens makes them adopt different ways to perform AS. Mammals and fungi conduct a two-step transesterification reaction by spliceosomes to splice each individual mRNA (named cis -splicing). Parasites also use spliceosomes to splice, but this splicing can occur among different mRNAs (named trans -splicing). Bacteria and viruses directly hijack the host's splicing machinery to accomplish this process. Infection-related changes are reflected in the spliceosome behaviors and the characteristics of various splicing regulators (abundance, modification, distribution, movement speed, and conformation), which further radiate to alterations in the global splicing profiles. Genes with splicing changes are enriched in immune-, growth-, or metabolism-related pathways, highlighting approaches through which hosts crosstalk with pathogens. Based on these infection-specific regulators or AS events, several targeted agents have been developed to fight against pathogens. Here, we summarized recent findings in the field of infection-related splicing, including splicing mechanisms of pathogens and hosts, splicing regulation and aberrant AS events, as well as emerging targeted drugs. We aimed to systemically decode host-pathogen interactions from a perspective of splicing. We further discussed the current strategies of drug development, detection methods, analysis algorithms, and database construction, facilitating the annotation of infection-related splicing and the integration of AS with disease phenotype.
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Affiliation(s)
- Mengyuan Lyu
- Department of Laboratory Medicine, West China Hospital, Sichuan University, Chengdu, Sichuan 610041, China
| | - Hongli Lai
- Department of Laboratory Medicine, West China Hospital, Sichuan University, Chengdu, Sichuan 610041, China
| | - Yili Wang
- Department of Laboratory Medicine, West China Hospital, Sichuan University, Chengdu, Sichuan 610041, China
| | - Yanbing Zhou
- Department of Laboratory Medicine, West China Hospital, Sichuan University, Chengdu, Sichuan 610041, China
| | - Yi Chen
- Department of Laboratory Medicine, West China Hospital, Sichuan University, Chengdu, Sichuan 610041, China
| | - Dongsheng Wu
- Department of Thoracic Surgery and Institute of Thoracic Oncology, West China Hospital, Sichuan University, Chengdu, Sichuan 610041, China
| | - Jie Chen
- Department of Laboratory Medicine, West China Hospital, Sichuan University, Chengdu, Sichuan 610041, China
| | - Binwu Ying
- Department of Laboratory Medicine, West China Hospital, Sichuan University, Chengdu, Sichuan 610041, China
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Epidemiological and Cytokine Profile of Patients with Pulmonary and Extrapulmonary Tuberculosis in a Population of the Brazilian Amazon. Microorganisms 2022; 10:microorganisms10102075. [PMID: 36296351 PMCID: PMC9609616 DOI: 10.3390/microorganisms10102075] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/07/2022] [Revised: 10/13/2022] [Accepted: 10/17/2022] [Indexed: 11/16/2022] Open
Abstract
Several factors are associated with the development of different clinical forms of tuberculosis (TB). The present study evaluated epidemiological variables and cytokine levels in samples from 89 patients with TB (75 with pulmonary TB and 14 with extrapulmonary TB) and 45 controls. Cytokines were measured by flow cytometry (Human Th1/Th2/Th17 Cytometric Bead Array kit). The TB group had a higher frequency of individuals who were 39 years of age or older, married, with primary education or illiterate and had a lower family income (p < 0.05). All individuals with extrapulmonary TB reported that they were not working, and the main reasons were related to disease symptoms or treatment. The levels of IFN-γ (OR = 4.06) and IL-4 (OR = 2.62) were more likely to be elevated in the TB group (p = 0.05), and IFN-γ levels were lower in patients with extrapulmonary TB compared to those with pulmonary TB (OR = 0.11; p = 0.0050). The ROC curve was applied to investigate the diagnostic accuracy of IFN-γ levels between the different clinical forms of tuberculosis, resulting in high AUC (0.8661; p < 0.0001), sensitivity (93.85%) and specificity median (65.90%), suggesting that IFN-γ levels are useful to differentiate pulmonary TB from extrapulmonary TB. The dysregulation of pro- and anti-inflammatory cytokine levels represent a risk for the development of TB and contribute to the pathogenesis of the disease, especially variation in IFN-γ levels, which may determine protection or risk for extrapulmonary TB.
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Gebremicael G, Gebreegziabxier A, Kassa D. Low transcriptomic of PTPRCv1 and CD3E is an independent predictor of mortality in HIV and tuberculosis co-infected patient. Sci Rep 2022; 12:10133. [PMID: 35710869 PMCID: PMC9203579 DOI: 10.1038/s41598-022-14305-8] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/12/2022] [Accepted: 06/06/2022] [Indexed: 11/09/2022] Open
Abstract
A comprehensive assessment of immunological profiles during HIV-TB co-infection is essential to predict mortality, and facilitate the development of effective diagnostic assays, therapeutic agents, and vaccines. Expression levels of 105 immune-related genes were measured at enrolment and 6th month follow-up from 9 deceased HIV and TB coinfected patients who died between 3 and 7th months follow-up and at enrolment, 6th and 18th month from 18 survived matched controls groups for 2 years. Focused gene expression profiling was assessed from peripheral whole blood using a dual-color Reverse-Transcription Multiplex Ligation-dependent Probe Amplification assay. Eleven of the 105 selected genes were differentially expressed between deceased individuals and survivor-matched controls at baseline. At baseline, IL4δ2 was significantly more highly expressed in the deceased group than survivor matched controls, whereas CD3E, IL7R, PTPRCv1, CCL4, GNLY, BCL2, CCL5, NOD1, TLR3, and NLRP13 had significantly lower expression levels in the deceased group compared to survivor matched controls. At baseline, a non-parametric receiver operator characteristic curve was conducted to determine the prediction of mortality of single genes identified CCL5, PTPRCv1, CD3E, and IL7R with Area under the Curve of 0.86, 0.86, 0.86, and 0.85 respectively. The expression of these genes in the survived control was increased at the end of TB treatment from that at baseline, while decreased in the deceased group. The expression of PTPRCv1, CD3E, CCL5, and IL7R host genes in peripheral blood of patients with TB-HIV coinfected can potentially be used as a predictor of mortality in the Ethiopian setting. Anti-TB treatment might be less likely to restore gene expression in the level expression of the deceased group. Therefore, other new therapeutics that can restore these genes (PTPRCv1, CD3E, IL7R, and CCL5) in the deceased groups at baseline might be needed to save lives.
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Affiliation(s)
| | | | - Desta Kassa
- Ethiopian Public Health Institute (EPHI), P.O.Box: 1242, Addis Ababa, Ethiopia
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5
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Pooran A, Davids M, Nel A, Shoko A, Blackburn J, Dheda K. IL-4 subverts mycobacterial containment in Mycobacterium tuberculosis-infected human macrophages. Eur Respir J 2019; 54:13993003.02242-2018. [PMID: 31097521 DOI: 10.1183/13993003.02242-2018] [Citation(s) in RCA: 17] [Impact Index Per Article: 3.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/26/2018] [Accepted: 05/07/2019] [Indexed: 12/17/2022]
Abstract
Protective immunity against Mycobacterium tuberculosis is poorly understood. The role of interleukin (IL)-4, the archetypal T-helper type 2 (Th2) cytokine, in the immunopathogenesis of human tuberculosis remains unclear.Blood and/or bronchoalveolar lavage fluid (BAL) were obtained from participants with pulmonary tuberculosis (TB) (n=23) and presumed latent TB infection (LTBI) (n=22). Messenger RNA expression levels of interferon (IFN)-γ, IL-4 and its splice variant IL-4δ2 were determined by real-time PCR. The effect of human recombinant (hr)IL-4 on mycobacterial survival/containment (CFU·mL-1) was evaluated in M. tuberculosis-infected macrophages co-cultured with mycobacterial antigen-primed effector T-cells. Regulatory T-cell (Treg) and Th1 cytokine levels were evaluated using flow cytometry.In blood, but not BAL, IL-4 mRNA levels (p=0.02) and the IL-4/IFN-γ ratio (p=0.01) was higher in TB versus LTBI. hrIL-4 reduced mycobacterial containment in infected macrophages (p<0.008) in a dose-dependent manner and was associated with an increase in Tregs (p<0.001), but decreased CD4+Th1 cytokine levels (CD4+IFN-γ+ p<0.001; CD4+TNFα+ p=0.01). Blocking IL-4 significantly neutralised mycobacterial containment (p=0.03), CD4+IFNγ+ levels (p=0.03) and Treg expression (p=0.03).IL-4 can subvert mycobacterial containment in human macrophages, probably via perturbations in Treg and Th1-linked pathways. These data may have implications for the design of effective TB vaccines and host-directed therapies.
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Affiliation(s)
- Anil Pooran
- Centre for Lung Infection and Immunity, Division of Pulmonology, Dept of Medicine and UCT Lung Institute & South African MRC/UCT Centre for the Study of Antimicrobial Resistance, University of Cape Town, Cape Town, South Africa
| | - Malika Davids
- Centre for Lung Infection and Immunity, Division of Pulmonology, Dept of Medicine and UCT Lung Institute & South African MRC/UCT Centre for the Study of Antimicrobial Resistance, University of Cape Town, Cape Town, South Africa
| | - Andrew Nel
- Dept of Integrative Biomedical Sciences, Institute for Infectious Disease and Molecular Medicine, University of Cape Town, Cape Town, South Africa
| | - Aubrey Shoko
- Centre for Proteomics and Genomics Research, Cape Town, South Africa
| | - Jonathan Blackburn
- Dept of Integrative Biomedical Sciences, Institute for Infectious Disease and Molecular Medicine, University of Cape Town, Cape Town, South Africa
| | - Keertan Dheda
- Centre for Lung Infection and Immunity, Division of Pulmonology, Dept of Medicine and UCT Lung Institute & South African MRC/UCT Centre for the Study of Antimicrobial Resistance, University of Cape Town, Cape Town, South Africa .,Faculty of Infectious and Tropical Diseases, Dept of Immunology and Infection, London School of Hygiene and Tropical Medicine, London, UK
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Marín ND, García LF. The role of CD30 and CD153 (CD30L) in the anti-mycobacterial immune response. Tuberculosis (Edinb) 2016; 102:8-15. [PMID: 28061955 DOI: 10.1016/j.tube.2016.10.006] [Citation(s) in RCA: 12] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/25/2016] [Revised: 10/10/2016] [Accepted: 10/29/2016] [Indexed: 12/01/2022]
Abstract
The establishment of a protective T-cell response against mycobacterial infections involves different co-stimulatory molecules and their respective ligands. Among these molecules the Tumor Necrosis Factor Receptor Super-family (TNFRSF) and the Tumor Necrosis Factor Super-family (TNFSF) are known to be important members. This review analyzes the evidence that CD30 and CD153 (CD30L), members of the TNFRSF and TNSF, play key roles in the T cell-dependent anti-mycobacterial immune response. Mice deficient in either CD30 or CD153, or treated with antibodies blocking the effects or CD30 and CD153, and infected with M.avium or M.bovis BCG exhibit higher bacterial burden, abnormal inflammatory responses with decreased Th1 responses, this is evidenced by the reduced number of IFN-γ-producing cells. Recent evidence also showed that CD30+ CD153+ Tγδ cells participate in the early stages of M.bovis BCG infection by producing IL-17A. In humans, stimulation of T-cells with mycobacterial antigens induces CD30 expression mainly by CD4+ cells; CD30+ cells have been demonstrated in tissues of patients with tuberculosis (TB) and in positive tuberculin skin test reactions. In addition, the levels of soluble CD30 are increased in serum and BAL of TB patients and these levels seems to correlate with the severity of the disease. These findings suggest that CD30/CD153 interactions during the anti-mycobacterial immune response are important for the establishment and maintenance of a protective response. Further studies would be required to determine whether these molecules may be good clinical biomarkers or potential targets for immune manipulation.
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Affiliation(s)
- Nancy D Marín
- Grupo de Inmunología Celular e Inmunogenética, Sede de Investigación Universitaria, Facultad de Medicina, Universidad de Antioquia, Medellín, Colombia; Escuela de Microbiología, Universidad de Antioquia, Medellín, Colombia
| | - Luis F García
- Grupo de Inmunología Celular e Inmunogenética, Sede de Investigación Universitaria, Facultad de Medicina, Universidad de Antioquia, Medellín, Colombia.
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Savolainen LE, Kantele A, Knuuttila A, Pusa L, Karttunen R, Valleala H, Tuuminen T. Combined Expression of IFN-γ, IL-17, and IL-4 mRNA by Recall PBMCs Moderately Discriminates Active Tuberculosis from Latent Mycobacterium tuberculosis Infection in Patients with Miscellaneous Inflammatory Underlying Conditions. Front Immunol 2016; 7:239. [PMID: 27379100 PMCID: PMC4905973 DOI: 10.3389/fimmu.2016.00239] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/07/2016] [Accepted: 06/03/2016] [Indexed: 11/23/2022] Open
Abstract
New biomarkers are needed for discriminating active tuberculosis (TB) from latent TB infection (LTBI), especially in vulnerable groups representing the major diagnostic challenge. This pilot study was carried out to explore the diagnostic potential of selected genes, IFN-γ, IL-17, IL-4, and FoxP3, associated with TB immunity and immunopathology. IFN-γ, IL-17, IL-4, and FoxP3 mRNA expression levels were measured by quantitative reverse transcription PCR (RT-qPCR) from antigen-stimulated peripheral blood mononuclear cells of patients with active TB (n = 25); patients with miscellaneous inflammatory disorders and concomitant LTBI (n = 20), rheumatoid arthritis (RA) being the most predominant in the group (n = 11); and in healthy Bacillus Calmette–Guérin (BCG) vaccinees (n = 8). While the levels of FoxP3 mRNA did not differ between the tested groups, the cumulative expression levels of purified protein derivative-stimulated IFN-γ, IL-17, and IL-4 mRNAs were found to distinguish active TB from the whole group of LTBI with 48% sensitivity and 85% specificity. When restricting the LTBI group to RA cases only, the sensitivity was 56% and specificity 100%. When interpreting the result as positive in at least one of the mRNAs IFN-γ, IL-17, or IL-4, sensitivity of 64% and specificities of 75% (heterogeneous group of LTBI) or 100% (LTBI with RA) were achieved. Moderate discrimination of active TB from LTBI with miscellaneous inflammatory underlying conditions by using combined quantitative expression of IFN-γ, IL-17, and IL-4 mRNA seems not to be of high diagnostic potential.
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Affiliation(s)
- Laura E Savolainen
- Department of Bacteriology and Immunology, Haartman Institute, University of Helsinki , Helsinki , Finland
| | - Anu Kantele
- Department of Bacteriology and Immunology, Haartman Institute, University of Helsinki, Helsinki, Finland; Department of Medicine, Division of Infectious Diseases, Helsinki University Central Hospital, Helsinki, Finland; Department of Medicine, Institute of Clinical Medicine, University of Helsinki, Helsinki, Finland
| | - Aija Knuuttila
- Heart and Lung Center, Helsinki University Central Hospital , Helsinki , Finland
| | - Liana Pusa
- Länsi-Uusimaa Hospital , Tammisaari , Finland
| | - Riitta Karttunen
- Department of Bacteriology and Immunology, Haartman Institute, University of Helsinki, Helsinki, Finland; Laboratory Division (HUSLAB), Helsinki University Central Hospital, Helsinki, Finland
| | - Heikki Valleala
- Department of Medicine, Division of Rheumatology, Helsinki University Central Hospital , Helsinki , Finland
| | - Tamara Tuuminen
- Department of Bacteriology and Immunology, Haartman Institute, University of Helsinki, Helsinki, Finland; Eastern Finland Laboratory Centre Joint Authority Enterprise, Mikkeli, Finland
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8
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A Mutation in IL4RA Is Associated with the Degree of Pathology in Human TB Patients. Mediators Inflamm 2016; 2016:4245028. [PMID: 26977119 PMCID: PMC4764744 DOI: 10.1155/2016/4245028] [Citation(s) in RCA: 8] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/21/2015] [Accepted: 01/12/2016] [Indexed: 12/16/2022] Open
Abstract
The contribution of interleukin- (IL-) 4 receptor-alpha- (Rα-) dependent events in the pathogenesis of tuberculosis (TB) is controversial. We have recently shown IL-13 overexpression in mice to cause recrudescent Mtb replication and centrally necrotizing granulomas strongly resembling pathology of human TB. A deletion of IL-4Rα completely abrogates TB tissue pathology in these mice. To validate our results in human TB patients, we here determined the association of distinct variants of the IL4, IL13, IL4RA, IL13RA1, and IL13RA2 genes with cavity formation in a large Ghanaian cohort of HIV-negative individuals with newly diagnosed pulmonary TB. In fact, the structural variant of the IL4RA I50V, previously shown to result in enhanced signal transduction, was significantly associated with greater cavity size, and a variant of IL13RA2 was associated with disease in females. To evaluate whether the human-like TB pathology in IL-13-overexpressing mice is specifically mediated through the IL-4Rα subunit, we analyzed IL-13 transgenic mice with a genetic ablation of the IL-4Rα. In these mice, the IL-13-mediated increased susceptibility, human-like pathology of collagen deposition around centrally necrotizing granulomas, and alternative macrophage activation were abolished. Together, our genetic association study in human TB patients further supports the assumption that IL-13/IL-4Rα-dependent mechanisms are involved in mediating tissue pathology of human TB.
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Heitmann L, Abad Dar M, Schreiber T, Erdmann H, Behrends J, Mckenzie ANJ, Brombacher F, Ehlers S, Hölscher C. The IL-13/IL-4Rα axis is involved in tuberculosis-associated pathology. J Pathol 2014; 234:338-50. [PMID: 24979482 PMCID: PMC4277691 DOI: 10.1002/path.4399] [Citation(s) in RCA: 79] [Impact Index Per Article: 7.9] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/13/2014] [Revised: 06/05/2014] [Accepted: 06/22/2014] [Indexed: 01/20/2023]
Abstract
Human tuberculosis (TB) is a leading global health threat and still constitutes a major medical challenge. However, mechanisms governing tissue pathology during post-primary TB remain elusive, partly because genetically or immunologically tractable animal models are lacking. In human TB, the demonstration of a large relative increase in interleukin (IL)-4 and IL-13 expression, which correlates with lung damage, indicates that a subversive T helper (TH)2 component in the response to Mycobacterium tuberculosis (Mtb) may undermine protective immunity and contribute to reactivation and tissue pathology. Up to now, there has been no clear evidence regarding whether IL-4/IL-13-IL-4 receptor-α (Rα)-mediated mechanisms may in fact cause reactivation and pathology. Unfortunately, the virtual absence of centrally necrotizing granulomas in experimental murine TB is associated with a poor induction of a TH2 immune response. We therefore hypothesize that, in mice, an increased production of IL-13 may lead to a pathology similar to human post-primary TB. In our study, aerosol Mtb infection of IL-13-over-expressing mice in fact resulted in pulmonary centrally necrotizing granulomas with multinucleated giant cells, a hypoxic rim and a perinecrotic collagen capsule, with an adjacent zone of lipid-rich, acid-fast bacilli-containing foamy macrophages, thus strongly resembling the pathology in human post-primary TB. Granuloma necrosis (GN) in Mtb-infected IL-13-over-expressing mice was associated with the induction of arginase-1-expressing macrophages. Indirect blockade of the endogenous arginase inhibitor l-hydroxyarginine in Mtb-infected wild-type mice resulted in a strong arginase expression and precipitated a similar pathology of GN. Together, we here introduce an experimental TB model that displays many features of centrally necrotizing granulomas in human post-primary TB and demonstrate that IL-13/IL-4Rα-dependent mechanisms leading to arginase-1 expression are involved in TB-associated tissue pathology.
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Affiliation(s)
- Lisa Heitmann
- Infection Immunology, Research Centre Borstel, Germany; Priority Research Area 'Infections', Research Centre Borstel, Germany
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The History of Tuberculosis and Bacillus Calmette–Guérin Vaccine in Iran. ARCHIVES OF PEDIATRIC INFECTIOUS DISEASES 2014. [DOI: 10.5812/pedinfect.20766] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/16/2022]
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Ashenafi S, Aderaye G, Bekele A, Zewdie M, Aseffa G, Hoang ATN, Carow B, Habtamu M, Wijkander M, Rottenberg M, Aseffa A, Andersson J, Svensson M, Brighenti S. Progression of clinical tuberculosis is associated with a Th2 immune response signature in combination with elevated levels of SOCS3. Clin Immunol 2014; 151:84-99. [PMID: 24584041 DOI: 10.1016/j.clim.2014.01.010] [Citation(s) in RCA: 57] [Impact Index Per Article: 5.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/16/2013] [Revised: 01/08/2014] [Accepted: 01/30/2014] [Indexed: 02/06/2023]
Abstract
In this study, we explored the local cytokine/chemokine profiles in patients with active pulmonary or pleural tuberculosis (TB) using multiplex protein analysis of bronchoalveolar lavage and pleural fluid samples. Despite increased pro-inflammation compared to the uninfected controls; there was no up-regulation of IFN-γ or the T cell chemoattractant CCL5 in the lung of patients with pulmonary TB. Instead, elevated levels of IL-4 and CCL4 were associated with high mycobacteria-specific IgG titres as well as SOCS3 (suppressors of cytokine signaling) mRNA and progression of moderate-to-severe disease. Contrary, IL-4, CCL4 and SOCS3 remained low in patients with extrapulmonary pleural TB, while IFN-γ, CCL5 and SOCS1 were up-regulated. Both SOCS molecules were induced in human macrophages infected with Mycobacterium tuberculosis in vitro. The Th2 immune response signature found in patients with progressive pulmonary TB could result from inappropriate cytokine/chemokine responses and excessive SOCS3 expression that may represent potential targets for clinical TB management.
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Affiliation(s)
- Senait Ashenafi
- Karolinska Institutet, Center for Infectious Medicine (CIM), F59, Department of Medicine, Karolinska University Hospital Huddinge, Stockholm, Sweden; Black Lion University Hospital and Addis Ababa University, Department of Pathology, Faculty of Medicine, Addis Ababa, Ethiopia
| | - Getachew Aderaye
- Black Lion University Hospital and Addis Ababa University, Department of Internal Medicine, Faculty of Medicine, Addis Ababa, Ethiopia
| | - Amsalu Bekele
- Black Lion University Hospital and Addis Ababa University, Department of Internal Medicine, Faculty of Medicine, Addis Ababa, Ethiopia
| | - Martha Zewdie
- Armauer Hansen Research Institute (AHRI), Addis Ababa, Ethiopia
| | - Getachew Aseffa
- Black Lion University Hospital and Addis Ababa University, Department of Radiology, Faculty of Medicine, Addis Ababa, Ethiopia
| | - Anh Thu Nguyen Hoang
- Karolinska Institutet, Center for Infectious Medicine (CIM), F59, Department of Medicine, Karolinska University Hospital Huddinge, Stockholm, Sweden
| | - Berit Carow
- Karolinska Institutet, Department of Microbiology, Tumor and Cell Biology (MTC), Stockholm, Sweden
| | - Meseret Habtamu
- Armauer Hansen Research Institute (AHRI), Addis Ababa, Ethiopia
| | - Maria Wijkander
- Karolinska Institutet, Center for Infectious Medicine (CIM), F59, Department of Medicine, Karolinska University Hospital Huddinge, Stockholm, Sweden
| | - Martin Rottenberg
- Karolinska Institutet, Department of Microbiology, Tumor and Cell Biology (MTC), Stockholm, Sweden
| | - Abraham Aseffa
- Armauer Hansen Research Institute (AHRI), Addis Ababa, Ethiopia
| | - Jan Andersson
- Karolinska Institutet, Center for Infectious Medicine (CIM), F59, Department of Medicine, Karolinska University Hospital Huddinge, Stockholm, Sweden; Karolinska University Hospital Huddinge, Department of Medicine, Division of Infectious Diseases, Stockholm, Sweden
| | - Mattias Svensson
- Karolinska Institutet, Center for Infectious Medicine (CIM), F59, Department of Medicine, Karolinska University Hospital Huddinge, Stockholm, Sweden
| | - Susanna Brighenti
- Karolinska Institutet, Center for Infectious Medicine (CIM), F59, Department of Medicine, Karolinska University Hospital Huddinge, Stockholm, Sweden.
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12
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Nolan A, Condos R, Huie ML, Dawson R, Dheda K, Bateman E, Rom WN, Weiden MD. Elevated IP-10 and IL-6 from bronchoalveolar lavage cells are biomarkers of non-cavitary tuberculosis. Int J Tuberc Lung Dis 2014; 17:922-7. [PMID: 23743311 DOI: 10.5588/ijtld.12.0610] [Citation(s) in RCA: 21] [Impact Index Per Article: 2.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/31/2022] Open
Abstract
BACKGROUND Active TB disease can destroy lung parenchyma leading to cavities. Immune responses that predispose or protect individuals from lung damage during TB are poorly defined. OBJECTIVE To sample lung immune cells and assay bronchoalveolar lavage (BAL) cell cytokine production. DESIGN Enrolled subjects (n = 73) had bilateral infiltrates and underwent BAL. RESULTS All had sputum culture demonstrating Mycobacterium tuberculosis and 22/73 (30%) had cavities on their chest radiograph. Those with cavities at presentation had a higher percentage of polymorphonuclear neutrophils (PMN) in BAL as well as lower inducible protein (IP) 10 (P < 0.01) and interleukin (IL) 6 (P = 0.013) in BAL cell supernatants compared to those without cavities. There was no correlation between cavities and other BAL or serum cytokines. IP-10 was negatively associated with BAL PMN. IP-10 and IL-6 expression above median reduces the odds of cavities by 79% and 78% in logistic regression models. IP-10 and IL-6 clustered with interferon-gamma and tumour necrosis factor-alpha in a principal component analysis, while IL-4 clustered with PMN. CONCLUSION Increasing IP-10 and IL-6 production by BAL cells is associated with non-cavitary TB in patients who present with radiographically advanced TB. IP-10 and IL-6 may reflect an effective T-helper 1 immune control pathway for TB, attenuating tuberculous lung destruction.
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Affiliation(s)
- A Nolan
- Division of Pulmonary, Critical Care, and Sleep Medicine, New York University School of Medicine, New York, NY 10016, USA
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13
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Dalmia N, Ramsay AJ. Prime-boost approaches to tuberculosis vaccine development. Expert Rev Vaccines 2013; 11:1221-33. [PMID: 23176655 DOI: 10.1586/erv.12.94] [Citation(s) in RCA: 39] [Impact Index Per Article: 3.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/21/2023]
Abstract
Four individuals die from active TB disease each minute, while at least 2 billion are latently infected and at risk for disease reactivation. BCG, the only licensed TB vaccine, is effective in preventing childhood forms of TB; however its poor efficacy in adults, emerging drug-resistant TB strains and tedious chemotherapy regimes, warrant the development of novel prophylactic measures. Designing safe and effective vaccines against TB will require novel approaches on several levels, including the administration of rationally selected mycobacterial antigens in efficient delivery vehicles via optimal immunization routes. Given the primary site of disease manifestation in the lungs, development of mucosal immunization strategies to generate protective immune responses both locally, and in the circulation, may be important for effective TB prophylaxis. This review focuses on prime-boost immunization strategies currently under investigation and highlights the potential of mucosal delivery and rational vaccine design based on systems biology.
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Affiliation(s)
- Neha Dalmia
- Department of Microbiology, Immunology, and Parasitology, Louisiana State University Health Sciences Center, 1901 Perdido Street, New Orleans, LA 70112, USA
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Nolan A, Fajardo E, Huie ML, Condos R, Pooran A, Dawson R, Dheda K, Bateman E, Rom WN, Weiden MD. Increased production of IL-4 and IL-12p40 from bronchoalveolar lavage cells are biomarkers of Mycobacterium tuberculosis in the sputum. PLoS One 2013; 8:e59461. [PMID: 23527200 PMCID: PMC3603887 DOI: 10.1371/journal.pone.0059461] [Citation(s) in RCA: 15] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/13/2012] [Accepted: 02/18/2013] [Indexed: 12/20/2022] Open
Abstract
BACKGROUND Tuberculosis (TB) causes 1.45 million deaths annually world wide, the majority of which occur in the developing world. Active TB disease represents immune failure to control latent infection from airborne spread. Acid-fast bacillus (AFB) seen on sputum smear is a biomarker for contagiousness. METHODS We enrolled 73 tuberculosis patients with extensive infiltrates into a research study using bronchoalveolar lavage (BAL) to sample lung immune cells and assay BAL cell cytokine production. All patients had sputum culture demonstrating Mycobacterium tuberculosis and 59/73 (81%) had AFB identified by microscopy of the sputum. Compared with smear negative patients, smear positive patients at presentation had a higher proportion with smoking history, a higher proportion with temperature >38.5(0) C, higher BAL cells/ml, lower percent lymphocytes in BAL, higher IL-4 and IL-12p40 in BAL cell supernatants. There was no correlation between AFB smear and other BAL or serum cytokines. Increasing IL-4 was associated with BAL PMN and negatively associated with BAL lymphocytes. Each 10-fold increase in BAL IL-4 and IL-12p40 increased the odds of AFB smear positivity by 7.4 and 2.2-fold, respectively, in a multi-variable logistic model. CONCLUSION Increasing IL-4 and IL-12p40 production by BAL cells are biomarkers for AFB in sputum of patients who present with radiographically advanced TB. They likely reflect less effective immune control of pathways for controlling TB, leading to patients with increased infectiousness.
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Affiliation(s)
- Anna Nolan
- Division of Pulmonary, Critical Care, and Sleep Medicine, New York University School of Medicine, New York, New York, United States of America
| | - Elaine Fajardo
- Division of Pulmonary, Critical Care, and Sleep Medicine, New York University School of Medicine, New York, New York, United States of America
| | - Maryann L. Huie
- Division of Pulmonary, Critical Care, and Sleep Medicine, New York University School of Medicine, New York, New York, United States of America
| | - Rany Condos
- Division of Pulmonary, Critical Care, and Sleep Medicine, New York University School of Medicine, New York, New York, United States of America
| | - Anil Pooran
- Lung Infection and Immunity Unit, CTBRI, Division of Pulmonology, Department of Medicine, University of Cape Town and Groote Schuur Hospital, Cape Town, South Africa
| | - Rodney Dawson
- Lung Infection and Immunity Unit, CTBRI, Division of Pulmonology, Department of Medicine, University of Cape Town and Groote Schuur Hospital, Cape Town, South Africa
| | - Keertan Dheda
- Lung Infection and Immunity Unit, CTBRI, Division of Pulmonology, Department of Medicine, University of Cape Town and Groote Schuur Hospital, Cape Town, South Africa
| | - Eric Bateman
- Lung Infection and Immunity Unit, CTBRI, Division of Pulmonology, Department of Medicine, University of Cape Town and Groote Schuur Hospital, Cape Town, South Africa
| | - William N. Rom
- Division of Pulmonary, Critical Care, and Sleep Medicine, New York University School of Medicine, New York, New York, United States of America
| | - Michael D. Weiden
- Division of Pulmonary, Critical Care, and Sleep Medicine, New York University School of Medicine, New York, New York, United States of America
- * E-mail:
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Luzina IG, Keegan AD, Heller NM, Rook GAW, Shea-Donohue T, Atamas SP. Regulation of inflammation by interleukin-4: a review of "alternatives". J Leukoc Biol 2012; 92:753-64. [PMID: 22782966 DOI: 10.1189/jlb.0412214] [Citation(s) in RCA: 242] [Impact Index Per Article: 20.2] [Reference Citation Analysis] [Abstract] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/15/2022] Open
Abstract
Studies of IL-4 have revealed a wealth of information on the diverse roles of this cytokine in homeostatic regulation and disease pathogenesis. Recent data suggest that instead of simple linear regulatory pathways, IL-4 drives regulation that is full of alternatives. In addition to the well-known dichotomous regulation of Th cell differentiation by IL-4, this cytokine is engaged in several other alternative pathways. Its own production involves alternative mRNA splicing, yielding at least two functional isoforms: full-length IL-4, encoded by the IL-4 gene exons 1-4, and IL-4δ2, encoded by exons 1, 3, and 4. The functional effects of these two isoforms are in some ways similar but in other ways quite distinct. When binding to the surface of target cells, IL-4 may differentially engage two different types of receptors. By acting on macrophages, a cell type critically involved in inflammation, IL-4 induces the so-called alternative macrophage activation. In this review, recent advances in understanding these three IL-4-related branch points--alternative splicing of IL-4, differential receptor engagement by IL-4, and differential regulation of macrophage activation by IL-4--are summarized in light of their contributions to inflammation.
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Affiliation(s)
- Irina G Luzina
- University of Maryland School of Medicine, Baltimore, MD 21201, USA
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16
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Hamzaoui K, Abid H, Berraies A, Ammar J, Hamzaoui A. NOD2 is highly expressed in Behçet disease with pulmonary manifestations. JOURNAL OF INFLAMMATION-LONDON 2012; 9:3. [PMID: 22330585 PMCID: PMC3310749 DOI: 10.1186/1476-9255-9-3] [Citation(s) in RCA: 21] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 04/11/2011] [Accepted: 02/13/2012] [Indexed: 01/28/2023]
Abstract
Background Excessive Th1 cells and TLRs functions are involved in the pathogenesis of Behcet's disease (BD) in response to bacterial antigens. NOD2, an intracellular pathogen recognition sensor, modulates innate defence to muropeptides derived from various bacterial species. To further define a role for NOD2 in BD, we analysed NOD2 transcriptional responses in BAL-MNC from BD patients with pulmonary manifestations. Methods We analysed NOD1, NOD2, T-bet and TLRs mRNA expression with real-time polymerase chain-reaction in BAL cells obtained from 23 BD patients with pulmonary manifestations and their matched controls. Results We found that NOD2 mRNA expression was highly up-regulated in BAL cells from BD and sarcoidosis patients compared to healthy control group (P = 0.001). In BD patients, significant correlation was found between NOD2 and T-bet mRNA expression (r = 0.602; P = 0.0009). In BAL from BD patients, NOD2 and T-bet mRNA expression were significantly correlated with BAL-lymphocytes (r = 0.485, P = 0.010; r = 0684, P = 0.0001 respectively). NOD2 in BD was also correlated with TLR 2(r = 0.444; P = 0.021) and TLR 4 (r = 0.574; P = 0.001) mRNA expression. Conclusion Our results indicate that BAL-MNC from BD patients expressed NOD2 as a result of lung inflammation. TLRs and NOD2 synergize for the induction of proinflammatory cytokines. BAL inflammatory cells showed an increased Th1 situation as indicated by increased T-bet mRNA expression.
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Affiliation(s)
- Kamel Hamzaoui
- Division of Histology and Immunology, Department of Basic Sciences, Medicine School of Tunis, Tunis El Manar University, 15 Rue Djebel Lakdar, 1007 Tunis, Tunisia.
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Luzina IG, Lockatell V, Lavania S, Pickering EM, Kang PH, Bashkatova YN, Andreev SM, Atamas SP. Natural production and functional effects of alternatively spliced interleukin-4 protein in asthma. Cytokine 2012; 58:20-6. [PMID: 22249152 DOI: 10.1016/j.cyto.2011.12.017] [Citation(s) in RCA: 16] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/29/2011] [Revised: 11/13/2011] [Accepted: 12/22/2011] [Indexed: 11/29/2022]
Abstract
We have previously described an alternatively spliced isoform of IL-4 mRNA that omits exon 2 and is termed IL-4δ2. However, the natural production of IL-4δ2 protein and its association with disease have not been previously assessed due to unavailability of an antibody that interacts with IL-4δ2 without cross-reactivity with full length IL-4. We used a unique monoclonal antibody (mAb) that reacts with IL-4δ2, but not with IL-4, and observed that IL-4δ2 is naturally produced by T cells from patients with asthma, but not from healthy controls. The kinetics of IL-4δ2 and IL-4 production by phorbol myristate acetate (PMA)/ionomycin-activated cells differed, with IL-4δ2 increasing at 48-72h and IL-4 peaking at 24h. The steady-state levels of IL-4δ2 mRNA varied significantly among the donors and were discordant with the corresponding protein levels, suggesting post-transcriptional regulation of protein production. Polarized Th1 or Th2 lymphocytes were not a major source of IL-4δ2. Stimulation of cultured T lymphocytes with IL-4δ2 caused elevated production of IFN-γ, IL-10, IL-6, MCP-1, and TNF-α, with notable differences between patients and controls in the production of IFN-γ, IL-10, and IL-6. Thus, IL-4δ2 is natively produced not only as mRNA but also as a protein by cells other than Th1 or Th2. It is regulated post-transcriptionally, is associated with allergic asthma, and regulates production of other cytokines by primary T lymphocytes. Alternatively spliced interleukin-4 may be a new biomarker, a pathophysiological player, and possibly a molecular target for future therapies in asthma.
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Affiliation(s)
- Irina G Luzina
- Department of Medicine, University of Maryland School of Medicine, Baltimore, MD 21201, USA
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John SH, Kenneth J, Gandhe AS. Host biomarkers of clinical relevance in tuberculosis: review of gene and protein expression studies. Biomarkers 2011; 17:1-8. [DOI: 10.3109/1354750x.2011.628048] [Citation(s) in RCA: 24] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/13/2022]
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Hussain R, Talat N, Ansari A, Shahid F, Hasan Z, Dawood G. Endogenously activated interleukin-4 differentiates disease progressors and non-progressors in tuberculosis susceptible families: a 2-year biomarkers follow-up study. J Clin Immunol 2011; 31:913-23. [PMID: 21755390 DOI: 10.1007/s10875-011-9566-y] [Citation(s) in RCA: 13] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/22/2011] [Accepted: 06/29/2011] [Indexed: 01/09/2023]
Abstract
OBJECTIVE Dynamic cytokine profiles from endogenously activated T cells in transit from lymph node to the infected sites via the blood compartment after recent exposure to Mycobacterium tuberculosis may differentiate disease progressors from non-disease progressors in a BCG-vaccinated population. METHODS Household contacts (N = 107) from families with (six families) or without (14 families) secondary cases were assessed for Types 1 and 2 cytokines serially in plasma of whole blood cultures without exogenous stimulation. "ARMS" PCR was carried out for detection of single nucleotide polymorphism T/A in IFN-γ +874. RESULTS In the absence of IFN-γ expansion, raised IL-4 at 6 months was associated with disease progression in TB-susceptible families. Resistant families on the other hand showed overrepresentation of IFN-γ +874 A allele and expansion of IFN-γ secreting cells at 6 months followed by contraction at 12 months. CONCLUSION Six months may be an important checkpoint for biomarker assessment in high-risk individuals post-exposure.
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Affiliation(s)
- Rabia Hussain
- Department of Pathology and Microbiology, Aga Khan University, Stadium Road, P.O. Box 3500, Karachi, 74800, Pakistan.
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Increased (6 exon) interleukin-7 production after M. tuberculosis infection and soluble interleukin-7 receptor expression in lung tissue. Genes Immun 2011; 12:513-22. [PMID: 21677672 DOI: 10.1038/gene.2011.29] [Citation(s) in RCA: 17] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/14/2022]
Abstract
Interleukin-7 (IL-7) and the IL-7 receptor (IL-7R) have been shown to be alternatively spliced in infectious diseases. We tested IL-7 and IL-7R splicing in a tuberculosis (TB)-vaccine/Mycobacterium tuberculosis (Mtb)-challenge model in non-human primates (NHPs). Differential IL-7 splicing was detected in peripheral blood mononuclear cells (PBMCs) from 15/15 NHPs showing 6 different IL-7 spliced isoforms. This pattern did not change after infection with virulent Mtb. We demonstrated increased IL-7 (6 exon) and IL-17 protein production in lung tissue along with concomitant decreased transforming growth factor-β (TGF-β) from NHPs (vaccinated with a recombinant BCG (rBCG)) who showed increased survival after Mtb challenge. IL-7 increased IL-17 and interferon-γ (IFN-γ) gene and protein expression in PBMCs. Mtb-infected NHPs showed differential IL-7R splicing associated with the anatomical location and tissue origin, that is, in lung tissue, hilus, axillary lymph nodes (LNs) and spleen. Differential splicing of the IL-7R was typical for healthy (non-Mtb infected) and for Mtb-infected lung tissue with a dominant expression of soluble IL-7R (sIL-7R) receptor lacking exon 6 (9:1 ratio of sIL-7R/cell-bound IL-7R). Differential ratios of cell-bound vs sIL-7R could be observed in hilus and axillary LNs from Mtb-infected NHPs with an inversed ratio of 1:9 (sIL-7R/cell-bound IL-7R) in spleen and PBMCs. Soluble IL-7R is exclusively present in lung tissue.
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Luzina IG, Lockatell V, Todd NW, Highsmith K, Keegan AD, Hasday JD, Atamas SP. Alternatively spliced variants of interleukin-4 promote inflammation differentially. J Leukoc Biol 2011; 89:763-70. [PMID: 21285395 DOI: 10.1189/jlb.0510271] [Citation(s) in RCA: 20] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/24/2022] Open
Abstract
IL-4δ2 is a natural splice variant of IL-4 that lacks the region encoded by the second exon. Numerous reports have suggested that the expression levels of IL-4δ2 change in various diseases, especially those with pulmonary involvement, but the in vivo effects of this splice variant have never been studied. Replication-deficient, AdV-mediated gene delivery of mIL-4δ2 to mouse lungs in vivo was used, and the effects compared with similar adenoviral delivery of mIL-4 or with infection with a noncoding NULL viral construct. Overexpression of IL-4δ2 or IL-4 caused pulmonary infiltration by T and B lymphocytes, whereas in contrast to IL-4, IL-4δ2 did not induce eosinophilia or goblet cell hyperplasia. Microarray analysis of global gene expression revealed that IL-4δ2 and IL-4 had differential effects on gene expression. These splice variants also differentially regulated pulmonary levels of the cytokines TNF-α, eotaxin, IL-1α, IFN-γ, and MCP-1, whereas both tended to increase total lung collagen modestly. Pulmonary infiltration by lymphocytes in response to overexpression of IL-4δ2 was attenuated but not abrogated completely by germline deficiency of IL-4Rα or STAT6, whereas deficiency of endogenous IL-4 had no effect. Thus, IL-4δ2 promotes lymphocytic inflammation in vivo (although differentially from IL-4, in part), and the effects of IL-4δ2 are not mediated by endogenous IL-4. Differential targeting of IL-4δ2 and IL-4 may therefore be considered in developing future therapeutic agents.
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Affiliation(s)
- Irina G Luzina
- Department of Medicine, University of Maryland School of Medicine, Baltimore, Maryland 21201, USA
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CCL2, CCL18 and sIL-4R in renal, meningeal and pulmonary TB; a 2 year study of patients and contacts. Tuberculosis (Edinb) 2011; 91:140-5. [PMID: 21251883 DOI: 10.1016/j.tube.2010.12.008] [Citation(s) in RCA: 14] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/20/2010] [Revised: 12/23/2010] [Accepted: 12/28/2010] [Indexed: 01/09/2023]
Abstract
The role of Th2 cytokines and Th2-associated chemokines in tuberculosis (TB) remains controversial, though in Mexico a polymorphism causing increased production of CCL2 is a risk factor. We studied levels of the Th2-associated chemokines CCL2 and CCL18, circulating soluble IL-4 receptors (sIL-4R), IL-4 and the inhibitory splice variant of IL-4 (IL-4δ2) in a cohort of patients with pulmonary TB and their healthy contacts. These were followed for 2 years during which time 10 contacts developed pulmonary TB. Results were compared with measurements made in renal and meningeal TB, and in disease controls with bacterial pneumonias or Dengue fever that have large Th2 components. In these disease controls both chemokines were significantly raised. They were also very significantly raised in all forms of TB, irrespective of age or disease site. Levels of CCL18 were raised least in meningeal TB, and most in pulmonary patients with long histories, when levels were similar to those in disease controls. Levels of CCL2, although also raised in all three forms of TB, were negatively correlated with CCL18. We found that levels of sIL-4R were strikingly reduced in all forms of TB, particularly meningeal. Contacts who progressed could not be distinguished from contacts who remained healthy at 2 years in terms of IL-4, sIL-4R, CCL2 or CCL18. However contacts had raised expression of IL-4δ2 as previously found. These results indicate vigorous and previously unrecorded activity within the Th2 axis, and further investigation is warranted.
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Luzina IG, Lockatell V, Todd NW, Keegan AD, Hasday JD, Atamas SP. Splice isoforms of human interleukin-4 are functionally active in mice in vivo. Immunology 2011; 132:385-93. [PMID: 21219317 DOI: 10.1111/j.1365-2567.2010.03393.x] [Citation(s) in RCA: 20] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/02/2023] Open
Abstract
Interleukin-4 (IL-4) acts on cultured cells in a species-specific fashion, although several reports have suggested that human (h) IL-4 may be functionally active in rodents in vivo. The latter finding, if true, would not only offer possibilities for pre-clinical testing of novel hIL-4-targeting therapies in animals, but also suggests new opportunities for mechanistic studies of IL-4 and its receptors. Conventional IL-4 is encoded by four exons, whereas its poorly studied alternatively spliced isoform is encoded by exons 1, 3 and 4 (IL-4δ2). Replication-deficient adenovirus-mediated gene delivery of hIL-4 isoforms (hIL-4 or hIL-4δ2) to mouse lungs caused similar pulmonary infiltration of T and B lymphocytes, but not eosinophils. There were significant differences in the changes of pulmonary cytokine milieu induced by hIL-4 compared with hIL-4δ2, with hIL-4δ2 inducing higher levels of pro-inflammatory (tumour necrosis factor-α, IL-1, and monocyte chemotactic protein-1) and T helper type 1 (IL-12 and interferon-γ) cytokines. There was no elevation in endogenous mouse (m) IL-4 or mIL-4δ2 mRNAs, and germ-line deficiency of mIL-4 did not affect the degree of pulmonary infiltration. When combined with an ovalbumin model of asthma, hIL-4δ2 stimulated a greater accumulation of lymphocytes than did hIL-4. Pulmonary infiltration of lymphocytes induced by expression of hIL-4 or hIL-4δ2 was attenuated, but not completely abrogated, by germ-line deficiency of mIL-4Rα or murine signal transducer and activator of transcription 6, suggesting that these signalling molecules mediate the in vivo effects of hIL-4 isoforms in mice. These findings suggest that splice isoforms of human IL-4 are functionally active in vivo in mice, and partially share the effects of the corresponding species-specific isoforms.
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Affiliation(s)
- Irina G Luzina
- Department of Medicine, University of Maryland School of Medicine, Baltimore, MD 21201, USA.
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Cloning of guinea pig IL-4: reduced IL-4 mRNA after vaccination or Mycobacterium tuberculosis infection. Tuberculosis (Edinb) 2010; 91:47-56. [PMID: 21167782 DOI: 10.1016/j.tube.2010.11.006] [Citation(s) in RCA: 14] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/09/2010] [Revised: 10/27/2010] [Accepted: 11/16/2010] [Indexed: 01/19/2023]
Abstract
Interleukin-4 (IL-4), a pleiotropic cytokine produced by T-helper type 2 (Th2) cells, is involved in promoting humoral immune responses, allergic reactions and asthma. Previous studies suggested an important role for IL-4 in susceptibility to pulmonary tuberculosis; however, the role of IL-4 has not been studied in the guinea pig, a highly relevant model for this disease. In the present study, we cloned a cDNA for guinea pig IL-4 and examined, for the first time, mRNA expression by real-time RT-PCR in cultured guinea pig cells. High levels of IL-4 mRNA expression were detected in spleen T cells of naïve animals after in vitro stimulation with PMA plus ionomycin for 4-24 h. The expression of IL-4 mRNA was low in spleen and lymph node cells immunized with ovalbumin (OVA) plus Complete Freund's Adjuvant (CFA) in response to OVA (Th1), but significantly higher in the guinea pigs immunized with OVA plus alum (Th2). BCG vaccination reduced the expression of IL-4 mRNA in both spleen and lung digest cells compared to naïve guinea pigs, while levels of IFN-γ were similar in both groups. Furthermore, lung cells from Mycobacterium tuberculosis-infected guinea pigs stimulated in vitro with PPD or MPT64 showed low levels of IL-4 mRNA expression. Thus, BCG vaccination or M. tuberculosis infection modulates IL-4 mRNA expression in the guinea pig. Cloning of guinea pig IL-4 will allow us to address the role of IL-4 in vaccine-induced resistance to pulmonary TB in a highly relevant animal model.
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Schwander S, Dheda K. Human lung immunity against Mycobacterium tuberculosis: insights into pathogenesis and protection. Am J Respir Crit Care Med 2010; 183:696-707. [PMID: 21075901 DOI: 10.1164/rccm.201006-0963pp] [Citation(s) in RCA: 75] [Impact Index Per Article: 5.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/28/2022] Open
Abstract
The study of human pulmonary immunity against Mycobacterium tuberculosis (M.tb) provides a unique window into the biological interactions between the human host and M.tb within the broncho-alveolar microenvironment, the site of natural infection. Studies of bronchoalveolar cells (BACs) and lung tissue evaluate innate, adaptive, and regulatory immune mechanisms that collectively contribute to immunological protection or its failure. In aerogenically M.tb-exposed healthy persons lung immune responses reflect early host pathogen interactions that may contribute to sterilization, the development of latent M.tb infection, or progression to active disease. Studies in these persons may allow the identification of biomarkers of protective immunity before the initiation of inflammatory and disease-associated immunopathological changes. In healthy close contacts of patients with tuberculosis (TB) and during active pulmonary TB, immune responses are compartmentalized to the lungs and characterized by an exuberant helper T-cell type 1 response, which as suggested by recent evidence is counteracted by local suppressive immune mechanisms. Here we discuss how exploring human lung immunity may provide insights into disease progression and mechanisms of failure of immunological protection at the site of the initial host-pathogen interaction. These findings may also aid in the identification of new biomarkers of protective immunity that are urgently needed for the development of new and the improvement of current TB vaccines, adjuvant immunotherapies, and diagnostic technologies. To facilitate further work in this area, methodological and procedural approaches for bronchoalveolar lavage studies and their limitations are also discussed.
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Affiliation(s)
- Stephan Schwander
- Department of Environmental and Occupational Health, UMDNJ-School of Public Health, 683 Hoes Lane West, Room 305, Piscataway, NJ 08854, USA.
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Möller M, Nebel A, van Helden PD, Schreiber S, Hoal EG. Analysis of eight genes modulating interferon gamma and human genetic susceptibility to tuberculosis: a case-control association study. BMC Infect Dis 2010; 10:154. [PMID: 20525402 PMCID: PMC2891757 DOI: 10.1186/1471-2334-10-154] [Citation(s) in RCA: 26] [Impact Index Per Article: 1.9] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/05/2010] [Accepted: 06/07/2010] [Indexed: 12/03/2022] Open
Abstract
Background Interferon gamma is a major macrophage-activating cytokine during infection with Mycobacterium tuberculosis, the causative pathogen of tuberculosis, and its role has been well established in animal models and in humans. This cytokine is produced by activated T helper 1 cells, which can best deal with intracellular pathogens such as M. tuberculosis. Based on the hypothesis that genes which regulate interferon gamma may influence tuberculosis susceptibility, we investigated polymorphisms in eight candidate genes. Methods Fifty-four polymorphisms in eight candidate genes were genotyped in over 800 tuberculosis cases and healthy controls in a population-based case-control association study in a South African population. Genotyping methods used included the SNPlex Genotyping System™, capillary electrophoresis of fluorescently labelled PCR products, TaqMan® SNP genotyping assays or the amplification mutation refraction system. Single polymorphisms as well as haplotypes of the variants were tested for association with TB using statistical analyses. Results A haplotype in interleukin 12B was nominally associated with tuberculosis (p = 0.02), but after permutation testing, done to assess the significance for the entire analysis, this was not globally significant. In addition a novel allele was found for the interleukin 12B D5S2941 microsatellite. Conclusions This study highlights the importance of using larger sample sizes when attempting validation of previously reported genetic associations. Initial studies may be false positives or may propose a stronger genetic effect than subsequently found to be the case.
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Affiliation(s)
- Marlo Möller
- Molecular Biology and Human Genetics, MRC Centre for Molecular and Cellular Biology, Faculty of Health Sciences, PO Box 19063, Stellenbosch University, Tygerberg 7505, South Africa.
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Wallis RS, Pai M, Menzies D, Doherty TM, Walzl G, Perkins MD, Zumla A. Biomarkers and diagnostics for tuberculosis: progress, needs, and translation into practice. Lancet 2010; 375:1920-37. [PMID: 20488517 DOI: 10.1016/s0140-6736(10)60359-5] [Citation(s) in RCA: 302] [Impact Index Per Article: 21.6] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 11/20/2022]
Abstract
Human infection with Mycobacterium tuberculosis can progress to active disease, be contained as latent infection, or be eradicated by the host response. Tuberculosis diagnostics classify a patient into one of these categories. These are not fixed distinct states, but rather are continua along which patients can move, and are affected by HIV infection, immunosuppressive therapies, antituberculosis treatments, and other poorly understood factors. Tuberculosis biomarkers-host or pathogen-specific-provide prognostic information, either for individual patients or study cohorts, about these outcomes. Tuberculosis case detection remains difficult, partly because of inaccurate diagnostic methods. Investments have yielded some progress in development of new diagnostics, although the existing pipeline is limited for tests for sputum-smear-negative cases, childhood tuberculosis, and accurate prediction of reactivation of latent tuberculosis. Despite new, sensitive, automated molecular platforms for detection of tuberculosis and drug resistance, a simple, inexpensive point-of-care test is still not available. The effect of any new tests will depend on the method and extent of their introduction, the strength of the laboratories, and the degree to which access to appropriate therapy follows access to diagnosis. Translation of scientific progress in biomarkers and diagnostics into clinical and public health programmes is possible-with political commitment, increased funding, and engagement of all stakeholders.
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Redelman-Sidi G, Sepkowitz KA, Huang CK, Park S, Stiles J, Eagan J, Perlin DS, Pamer EG, Kamboj M. 2009 H1N1 influenza infection in cancer patients and hematopoietic stem cell transplant recipients. J Infect 2010; 60:257-63. [PMID: 20138188 DOI: 10.1016/j.jinf.2010.01.009] [Citation(s) in RCA: 77] [Impact Index Per Article: 5.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/15/2009] [Revised: 01/26/2010] [Accepted: 01/28/2010] [Indexed: 01/01/2023]
Abstract
OBJECTIVES Although usually mild, 2009 H1N1 Influenza has caused up to 6000 deaths in the US. To determine outcome in patients with cancer and/or hematopoietic stem cell transplant (HSCT), we reviewed our recent experience at Memorial Sloan-Kettering Cancer Center (MSKCC). METHODS During the initial NYC outbreak (May 19-June 30, 2009), all respiratory samples at MSKCC were tested for 2009 H1N1 influenza by DFA, culture, and RT-PCR. Medical records were reviewed for all cases. RESULTS During the 6-week period, 45(11%) of 394 tested patients were diagnosed with 2009 H1N1 Influenza. These included 29(17%) of 167 patients with hematologic conditions compared to 16(7%) of 226 with solid tumors (P < 0.01). 21(22%) of 96 tested HSCT recipients were positive. Cough (93%) and fever (91%) were common. Of 29 patients who were radiographically assessed, 8(27%) had lower airway disease. 17(37%) were hospitalized. None required mechanical ventilation. No deaths were attributed to influenza. All treated patients tolerated antiviral medication. CONCLUSIONS 2009 H1N1 Influenza caused mild symptoms in most patients with cancer and/or HSCT. None died or required mechanical ventilation. Immunosuppression from cancer or its treatment including HSCT may not be a substantial risk for poor outcome, however further studies are needed to validate our results.
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Al-Attiyah RJ, Mustafa AS. Mycobacterial antigen-induced T helper type 1 (Th1) and Th2 reactivity of peripheral blood mononuclear cells from diabetic and non-diabetic tuberculosis patients and Mycobacterium bovis bacilli Calmette-Guérin (BCG)-vaccinated healthy subjects. Clin Exp Immunol 2009; 158:64-73. [PMID: 19737232 DOI: 10.1111/j.1365-2249.2009.04000.x] [Citation(s) in RCA: 48] [Impact Index Per Article: 3.2] [Reference Citation Analysis] [Abstract] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/15/2023] Open
Abstract
Patients with diabetes mellitus are more susceptible to tuberculosis (TB), and the clinical conditions of diabetic TB patients deteriorate faster than non-diabetic TB patients, but the immunological basis for this phenomenon is not understood clearly. Given the role of cell-mediated immunity (CMI) in providing protection against TB, we investigated whether CMI responses in diabetic TB patients are compromised. Peripheral blood mononuclear cells (PBMC) obtained from diabetic TB patients, non-diabetic TB patients and Mycobacterium bovis bacilli Calmette-Guérin (BCG)-vaccinated healthy subjects were cultured in the presence of complex mycobacterial antigens and pools of M. tuberculosis regions of difference (RD)1, RD4, RD6 and RD10 peptides. The PBMC were assessed for antigen-induced cell proliferation and secretion of T helper 1 (Th1) [interferon (IFN)-gamma, interleukin (IL)-2, tumour necrosis factor (TNF)-beta], and Th2 (IL-4, IL-5, IL-10) cytokines as CMI parameters. All the complex mycobacterial antigens and RD1(pool) stimulated strong proliferation of PBMC of all groups, except moderate responses to RD1(pool) in healthy subjects. In response to complex mycobacterial antigens, both IFN-gamma and TNF-beta were secreted by PBMC of all groups whereas diabetic TB patients secreted IL-10 with concentrations higher than the other two groups. Furthermore, in response to RD peptides, IFN-gamma and IL-10 were secreted by PBMC of diabetic TB patients only. The analyses of data in relation to relative cytokine concentrations showed that diabetic TB patients had lower Th1 : Th2 cytokines ratios, and a higher Th2 bias. The results demonstrate a shift towards Th2 bias in diabetic TB patients which may explain, at least in part, a faster deterioration in their clinical conditions.
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Affiliation(s)
- R J Al-Attiyah
- Department of Microbiology, Kuwait University, Safat, Kuwait.
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Kalsdorf B, Scriba TJ, Wood K, Day CL, Dheda K, Dawson R, Hanekom WA, Lange C, Wilkinson RJ. HIV-1 infection impairs the bronchoalveolar T-cell response to mycobacteria. Am J Respir Crit Care Med 2009; 180:1262-70. [PMID: 19797156 DOI: 10.1164/rccm.200907-1011oc] [Citation(s) in RCA: 120] [Impact Index Per Article: 8.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/12/2023] Open
Abstract
RATIONALE The risk of developing active tuberculosis in persons with latent Mycobacterium tuberculosis infection is substantially increased shortly after HIV-1 seroconversion. Immune responses in the lung are important to restrict the growth of M. tuberculosis to prevent the development of disease. OBJECTIVES To investigate innate and adaptive immune responses to M. tuberculosis in bronchoalveolar lavage from HIV-1-infected persons without active tuberculosis. METHODS Peripheral blood was drawn and bronchoalveolar lavage (BAL) performed on healthy, HIV-1-uninfected (n = 21) and HIV-1-infected (n = 15) adults. Growth of M. tuberculosis was assessed in monocytes and alveolar macrophages. Cytokine expression by mycobacteria-specific CD4 and CD8 T cells was measured by intracellular cytokine staining or IFN-gamma ELISpot. MEASUREMENTS AND MAIN RESULTS Mycobacterial growth in monocytes or alveolar macrophages from HIV-1-infected and -uninfected persons did not differ. Total CD4 T-cell frequencies in BAL were lower in HIV-1-infected than in HIV-1-uninfected persons (P < 0.001). Mycobacteria (bacillus Calmette-Guérin)-specific CD4 T-cell responses in BAL were severely impaired: Frequencies of cells expressing IFN-gamma or tumor necrosis factor (TNF)-alpha, as well as polyfunctional cells, expressing IFN-gamma, TNF-alpha, and IL-2 together, were lower in HIV-1-infected persons than in uninfected controls (P < 0.01 for all). CONCLUSIONS In addition to a total CD4 T-cell deficit, the function of mycobacteria-specific CD4 T cells is significantly impaired in the lung of HIV-1-infected persons, which may account for the HIV-1-associated elevated risk for developing tuberculosis.
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Affiliation(s)
- Barbara Kalsdorf
- Clinical Infectious Diseases Research Initiative, University of Cape Town, Observatory, South Africa
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31
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Rook GAW, Hernández-Pando R, Zumla A. Tuberculosis Due to High-Dose Challenge in Partially Immune Individuals: A Problem for Vaccination? J Infect Dis 2009; 199:613-8. [DOI: 10.1086/596654] [Citation(s) in RCA: 23] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/30/2023] Open
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Biomarkers for tuberculosis disease activity, cure, and relapse. THE LANCET. INFECTIOUS DISEASES 2009; 9:162-72. [DOI: 10.1016/s1473-3099(09)70042-8] [Citation(s) in RCA: 125] [Impact Index Per Article: 8.3] [Reference Citation Analysis] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 11/23/2022]
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Pleural tuberculosis in patients with early HIV infection is associated with increased TNF-alpha expression and necrosis in granulomas. PLoS One 2009; 4:e4228. [PMID: 19156215 PMCID: PMC2626629 DOI: 10.1371/journal.pone.0004228] [Citation(s) in RCA: 35] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/20/2008] [Accepted: 11/23/2008] [Indexed: 11/20/2022] Open
Abstract
Although granulomas may be an essential host response against persistent antigens, they are also associated with immunopathology. We investigated whether HIV co-infection affects histopathological appearance and cytokine profiles of pleural granulomas in patients with active pleural tuberculosis (TB). Granulomas were investigated in pleural biopsies from HIV positive and negative TB pleuritis patients. Granulomas were characterised as necrotic or non-necrotic, graded histologically and investigated for the mRNA expression of IL-12, IFN-gamma, TNF-alpha and IL-4 by in situ hybridisation. In all TB patients a mixed Th1/Th2 profile was noted. Necrotic granulomas were more evident in HIV positive patients with a clear association between TNF-alpha and necrosis. This study demonstrates immune dysregulation which may include TNF-alpha-mediated immunopathology at the site of disease in HIV infected pleural TB patients.
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Herrera MT, Torres M, Nevels D, Perez-Redondo CN, Ellner JJ, Sada E, Schwander SK. Compartmentalized bronchoalveolar IFN-gamma and IL-12 response in human pulmonary tuberculosis. Tuberculosis (Edinb) 2008; 89:38-47. [PMID: 18848499 DOI: 10.1016/j.tube.2008.08.002] [Citation(s) in RCA: 28] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/18/2008] [Revised: 06/12/2008] [Accepted: 08/18/2008] [Indexed: 01/13/2023]
Abstract
Human tuberculosis (TB) principally involves the lungs, where local immunity impacts on the load of Mycobacterium tuberculosis (M.tb). Because concomitants of local Th1 immunity are still under-explored in humans, we characterized immune responses in bronchoalveolar cells (BACs) and systemically in peripheral blood mononuclear cells (PBMCs) in persons with active pulmonary TB and in healthy community controls. PPD- and live M.tb-induced IFN-gamma-production were observed in CD4(+), CD8(+), gammadeltaTCR(+), and CD56(+) alveolar T cell subpopulations and NK cells (CD3(-)CD56(+)). IFN-gamma-producing CD4(+) T cells (mostly CD45RO(+)) were more abundant (p<0.05). M.tb-induced IL-12p70, but interestingly also IL-4, was increased (p<0.05) in BACs from TB patients. Constitutive expression of IL-12Rbeta1 and IL-12Rbeta2 mRNA in BACs and PBMCs and IFN-gammaR1 in BACs was similar in both study groups. Data were normalized to account for differences in proportions of alveolar T cells and macrophages in the study groups. IFN-gamma-production and its induction by IL-12R engagement occur virtually unimpaired in the bronchoalveolar spaces of patients with pulmonary TB. The reasons for the apparent failure to control M. tuberculosis growth during active pulmonary TB disease is unknown but could be the expression of locally acting immunosuppressive mechanisms that subvert the antimycobacterial effects of IFN-gamma.
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Affiliation(s)
- Maria Teresa Herrera
- Departamento de Microbiologia, Instituto Nacional de Enfermedades Respiratorias, Mexico City, Mexico
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35
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Abstract
Tuberculosis is still a leading cause of death in low-income and middle-income countries, especially those of sub-Saharan Africa where tuberculosis is an epidemic because of the increased susceptibility conferred by HIV infection. The effectiveness of the Bacille Calmette Guérin (BCG) vaccine is partial, and that of treatment of latent tuberculosis is unclear in high-incidence settings. The routine diagnostic methods that are used in many parts of the world are still very similar to those used 100 years ago. Multidrug treatment, within the context of structured, directly observed therapy, is a cost-effective control strategy. Nevertheless, the duration of treatment needed reduces its effectiveness, as does the emergence of multidrug-resistant and extensively drug-resistant disease; the latter has recently become widespread. The rapid expansion of basic, clinical, and operational research, in addition to increasing knowledge of tuberculosis, is providing new diagnostic, treatment, and preventive measures. The challenge is to apply these advances to the populations most at risk. The development of a comprehensive worldwide plan to stop tuberculosis might facilitate this process by coordinating the work of health agencies. However, massive effort, political will, and resources are needed for this plan to succeed.
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Affiliation(s)
- Gary Maartens
- Division of Clinical Pharmacology, Department of Medicine, Faculty of Health Sciences, University of Cape Town Medical School, Cape Town, South Africa.
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36
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Lala S, Dheda K, Chang JS, Huggett JF, Kim LU, Johnson MA, Rook GAW, Keshav S, Zumla A. The pathogen recognition sensor, NOD2, is variably expressed in patients with pulmonary tuberculosis. BMC Infect Dis 2007; 7:96. [PMID: 17705850 PMCID: PMC2018706 DOI: 10.1186/1471-2334-7-96] [Citation(s) in RCA: 11] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/27/2007] [Accepted: 08/16/2007] [Indexed: 11/21/2022] Open
Abstract
Background NOD2, an intracellular pathogen recognition sensor, modulates innate defences to muropeptides derived from various bacterial species, including Mycobacterium tuberculosis (MTB). Experimentally, NOD2 attenuates two key putative mycobactericidal mechanisms. TNF-α synthesis is markedly reduced in MTB-antigen stimulated-mononuclear cells expressing mutant NOD2 proteins. NOD2 agonists also induce resistance to apoptosis, and may thus facilitate the survival of MTB in infected macrophages. To further define a role for NOD2 in disease pathogenesis, we analysed NOD2 transcriptional responses in pulmonary leucocytes and mononuclear cells harvested from patients with pulmonary tuberculosis (PTB). Methods We analysed NOD2 mRNA expression by real-time polymerase chain-reaction in alveolar lavage cells obtained from 15 patients with pulmonary tuberculosis and their matched controls. We compared NOD2 transcriptional responses, in peripheral leucocytes, before and after anti-tuberculous treatment in 10 patients. In vitro, we measured NOD2 mRNA levels in MTB-antigen stimulated-mononuclear cells. Results No significant differences in NOD2 transcriptional responses were detected in patients and controls. In some patients, however, NOD2 expression was markedly increased and correlated with toll-like-receptor 2 and 4 expression. In whole blood, NOD2 mRNA levels increased significantly after completion of anti-tuberculosis treatment. NOD2 expression levels did not change significantly in mononuclear cells stimulated with mycobacterial antigens in vitro. Conclusion There are no characteristic NOD2 transcriptional responses in PTB. Nonetheless, the increased levels of NOD2 expression in some patients with severe tuberculosis, and the increases in expression levels within peripheral leucocytes following treatment merit further studies in selected patient and control populations.
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Affiliation(s)
- Sanjay Lala
- Centre for Gastroenterology, Royal Free and University College Medical School & Royal Free Hospital NHS Trust, London, UK
| | - Keertan Dheda
- Centre for Infectious Diseases and International Health, Royal Free Hospital NHS Trust, London, UK
- Lung Infection and Immunity Unit, Department of Medicine, Division of Pulmonology, University of Cape Town, South Africa
| | - Jung-Su Chang
- Centre for Infectious Diseases and International Health, Royal Free Hospital NHS Trust, London, UK
| | - Jim F Huggett
- Centre for Infectious Diseases and International Health, Royal Free Hospital NHS Trust, London, UK
| | - Louise U Kim
- Centre for Infectious Diseases and International Health, Royal Free Hospital NHS Trust, London, UK
| | - Margaret A Johnson
- Dept. of Thoracic and HIV Medicine, Royal Free Hospital NHS Trust, London, UK
| | - Graham AW Rook
- Centre for Infectious Diseases and International Health, Royal Free Hospital NHS Trust, London, UK
| | - Satish Keshav
- Centre for Gastroenterology, Royal Free and University College Medical School & Royal Free Hospital NHS Trust, London, UK
| | - Alimuddin Zumla
- Centre for Infectious Diseases and International Health, Royal Free Hospital NHS Trust, London, UK
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Wu HP, Wu CL, Yu CC, Liu YC, Chuang DY. Efficiency of interleukin-4 expression in patients with tuberculosis and nontubercular pneumonia. Hum Immunol 2007; 68:832-8. [PMID: 17961771 DOI: 10.1016/j.humimm.2007.07.003] [Citation(s) in RCA: 8] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/03/2007] [Revised: 07/12/2007] [Accepted: 07/16/2007] [Indexed: 11/28/2022]
Abstract
In the early stage of Mycobacterium tuberculosis infection, macrophages, in cooperation with interferon-gamma, a Th1 effector, are the first line of defense. Interleukin (IL)-4, a Th2 effector, is known to downregulate interferon-gamma. It is believed that the expression levels of IL-4 and its splicing variant-IL-4delta2 might be associated with Mycobacterium tuberculosis infection and chest radiographic patterns. The IL-4 and IL-4delta2 expressions in stimulated peripheral blood mononuclear cells of 76 tuberculosis patients, 48 pneumonic patients. and 36 healthy control subjects were evaluated by nested reverse transcriptase-polymerase chain reaction, and the expression of glyceraldehydes-3-phosphate dehydrogenase was used as an internal reference. The results showed that IL-4 mRNA expression was significantly decreased in patients with tuberculosis and nontubercular pneumonia compared with that in controls. The IL-4delta2 mRNA expression was positively correlated with IL-4 mRNA expression in all cases. The ratio of IL-4delta2 to IL-4 mRNA expression in tubercular patients with a cavity on chest radiography was significantly lower than that in patients without a chest cavity. In conclusion, the ratio of IL-4delta2 to IL-4 mRNA expression may play a key role in disease severity for patients with pulmonary tuberculosis. From our observations, the IL-4 mRNA expression efficiency was attenuated in patients with pulmonary infection, either tuberculosis or pneumonia.
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Affiliation(s)
- Huang-Pin Wu
- Division of Pulmonary Medicine, Department of Internal Medicine, Chang Gung Memorial Hospital, Keelung, Taiwan, Republic of China
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Djoba Siawaya JF, Ruhwald M, Eugen-Olsen J, Walzl G. Correlates for disease progression and prognosis during concurrent HIV/TB infection. Int J Infect Dis 2007; 11:289-99. [PMID: 17446108 DOI: 10.1016/j.ijid.2007.02.001] [Citation(s) in RCA: 46] [Impact Index Per Article: 2.7] [Reference Citation Analysis] [Abstract] [MESH Headings] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/09/2006] [Revised: 11/09/2006] [Accepted: 02/01/2007] [Indexed: 12/11/2022] Open
Abstract
Mycobacterium tuberculosis (Mtb) and the human immunodeficiency virus (HIV) are both life-threatening pathogens in their own right, but their synergic effects on the immune system during co-infection markedly enhance their effect on the host. This review focuses on the bidirectional interaction between HIV and Mtb and discusses the relevance of sputum smear examination, CD4+ counts, viral load at baseline and after initiation of anti-retroviral therapy, as well as additional existing and new potential immune correlates of disease progression and prognosis. These markers include beta2-microglobulin, neopterin, tumor necrosis factor receptor II (TNFRII), CD8+/CD38+, soluble urokinase plasminogen activator receptor (suPAR) and CXCL10 (or IP-10).
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Affiliation(s)
- Joel Fleury Djoba Siawaya
- Immunology Unit, Department of Biomedical Sciences, DST/NRF Center of Excellence in Biomedical TB Research, Faculty of Health Sciences, University of Stellenbosch, PO Box 19063, Tygerberg 7505, South Africa.
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The stability of mRNA encoding IL-4 is increased in pulmonary tuberculosis, while stability of mRNA encoding the antagonistic splice variant, IL-4delta2, is not. Tuberculosis (Edinb) 2006; 87:237-41. [PMID: 17196882 DOI: 10.1016/j.tube.2006.11.001] [Citation(s) in RCA: 15] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/24/2006] [Revised: 10/19/2006] [Accepted: 11/01/2006] [Indexed: 10/23/2022]
Abstract
The prototype Th2 cytokine IL-4, and its competitive antagonist IL-4delta2, may be important determinants of outcome in human tuberculosis (TB). However, there are no data on how gene expression of these cytokines is regulated. To evaluate this the stability of IL-4 and IL-4delta2 mRNA after the addition of actinomycin-D, was evaluated in whole blood from subjects with pulmonary TB and uninfected healthy volunteers. The Th2/Th1 (IL-4/IFN-gamma) mRNA ratio in unstimulated cells in whole blood was significantly greater in TB subjects than in controls (p<0.05). The mRNA half-life of the agonist (IL-4), but not the antagonist (IL-4delta2), was significantly prolonged in subjects with TB compared to healthy volunteers ( approximately 5-fold, p=0.0016), and the IL-4/IL-4delta2 ratio was higher in TB patients compared to controls (p<0.05). The differential stability of the Th2 agonist, IL-4, compared to the antagonist IL-4delta2, represents a hitherto undescribed post-transcriptional regulatory mechanism that may modulate the polarisation of Th1/Th2 responses in human TB.
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Lee S, Watson MW, Clark B, Flexman JP, Cheng W, French MAH, Price P. Hepatitis C virus genotype and HIV coinfection affect cytokine mRNA levels in unstimulated PBMC but do not shift the T1/T2 balance. Immunol Cell Biol 2006; 84:390-5. [PMID: 16834574 DOI: 10.1111/j.1440-1711.2006.01451.x] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/13/2023]
Abstract
Rapid progression of hepatitis C virus (HCV) disease in patients with HIV/HCV may reflect different cytokine responses and be influenced by HCV genotype. This is addressed by a study of patients with HIV/HCV coinfection and infection with HCV genotype 2 or 3 (2/3). They are compared with coinfected patients infected with genotype 1 and HCV monoinfected patients matched for HCV genotype. IFN-gamma, IL-10, IL-4 and IL-4delta2 mRNA were quantified by real-time PCR in unstimulated PBMC and after in vitro stimulation with HCV core or nonstructural 3/4A antigen. In unstimulated PBMC, levels of IFN-gamma and IL-4 mRNA were lowest in HIV/HCV genotype 1 patients, intermediate in HIV/HCV genotype 2/3 patients and highest in HCV genotype 2/3 patients. Neither HCV genotype nor HIV affected levels of IL-10 mRNA in unstimulated PBMC or IFN-gamma, IL-4 and IL-10 mRNA in PBMC stimulated with HCV antigens. Levels of IL-4 and IL-4delta2 mRNA correlated in mitogen-stimulated PBMC from all patient groups but both were low in HIV/HCV genotype 1 patients. Serum soluble CD30 levels (a putative marker of a T2 cytokine environment) did not differ between patient groups. The data do not suggest a shift in the T1/T2 balance driven by HIV coinfection or HCV genotype but either may affect IL-4 bioavailability.
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Affiliation(s)
- Silvia Lee
- Department of Clinical Immunology and Biochemical Genetics, Royal Perth Hospital, Perth, Western Australia, Australia.
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Price P, Keane NM, Lee S, Lim AFY, McKinnon EJ, French MA. A T2 cytokine environment may not limit T1 responses in human immunodeficiency virus patients with a favourable response to antiretroviral therapy. Immunology 2006; 119:74-82. [PMID: 16792698 PMCID: PMC1782334 DOI: 10.1111/j.1365-2567.2006.02407.x] [Citation(s) in RCA: 11] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/16/2006] [Revised: 04/26/2006] [Accepted: 04/27/2006] [Indexed: 12/31/2022] Open
Abstract
Low-level production of interferon-gamma (IFN-gamma) marks human immunodeficiency virus (HIV)-induced immunodeficiency and has been ascribed to a bias towards T2 cytokines. This was investigated in two cross-sectional studies of HIV patients who were immunodeficient when they began antiretroviral therapy (ART) and had stable increases in CD4 T-cell counts. Blood leucocytes were assessed unstimulated or after stimulation with cytomegalovirus (CMV), anti-CD3 or mitogen. IFN-gamma and interleukin (IL)-5 responses were initially assessed by enzyme-linked immunosorbent spot-forming cell assay (ELISPOT) and enzyme-linked immunosorbent assay (ELISA). We then adopted a sensitive reverse transcription-polymerase chain reaction (RT-PCR) system to assess IFN-gamma, IL-5, IL-4 and IL-4delta2 (an inhibitory splice variant of IL-4) mRNA. The results were correlated with putative serological markers of a T1 [lymphocyte activation gene-3 (LAG-3), CD26] or a T2 [CD30, immunoglobulin E (IgE)] cytokine environment. IL-5 production and IgE levels were elevated in patients. IgE levels did not correlate with IFN-gamma, but showed an inverse correlation with IL-5 released in culture (P = 0.05). The levels of IL-4, IFN-gamma, IL-5 and IL-4delta2 mRNA were correlated after anti-CD3 stimulation, where IL-5 was the best predictor of IFN-gamma mRNA (P = 0.006). Weak positive correlations were evident between CD30 and cytokine mRNA levels, whilst IgE correlated inversely with IL-4, IL-4delta2, IL-5 and IFN-gamma mRNA levels. These analyses provide no evidence for an inverse relationship between T1 and T2 cytokine responses in HIV patients, but suggest that the elevation of IgE marks low cytokine responses.
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Affiliation(s)
- Patricia Price
- School of Surgery and Pathology, University of Western Australia, Australia.
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Expression of IL-4 mRNA in peripheral blood mononuclear cells from normal donors in relation to expression of TLR2. Immunol Lett 2006; 106:194-7. [PMID: 16919700 DOI: 10.1016/j.imlet.2006.06.001] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/06/2006] [Revised: 06/01/2006] [Accepted: 06/06/2006] [Indexed: 11/22/2022]
Abstract
When IL-4 mRNA was distinguished from mRNA encoding its antagonist, the splice variant IL-4delta2, it was found to correlate directly with expression of TLR2 in fresh peripheral blood mononuclear cells (PBMCs) from normal donors (p=0.0013). Similarly IL-4 mRNA was high when TLR2 mRNA was abundant compared to levels of mRNA encoding its heterodimerisation partners TLR1 (p=0.0007) or TLR6 (p=0.0007). IL-4delta2 tended to show the reverse effect; IL-4delta2 mRNA was high when TLR2 was low relative to TLR1 (p=0.001). When subpopulations of the PBMCs were examined these relationships were found to be restricted to the CD3+ cells. The CD3+ cell population from 5 of 10 donors had detectable TLR2 mRNA. When levels of TLR1, IL-4 and IFN-gamma mRNA were assayed in the TLR2(low) and TLR2(high) CD3+ cells, it was found that IL-4 mRNA was restricted to the TLR2(high) T cells (p=0.007) while TLR1 was higher in the TLR2(low) T cells (p=0.015). IFN-gamma was also somewhat increased in the TLR2(low) (ns). None of these correlations with TLR mRNA expression levels were found in similar samples from tuberculosis patients, or when similar analyses were performed with data for IL-10 mRNA in cells from the same donors. We conclude that in T cell populations from normal donors, expression of IL-4 (but not of its antagonist, IL-4delta2, or of IL-10) is associated with high TLR2 and low TLR1.
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Demissie A, Wassie L, Abebe M, Aseffa A, Rook G, Zumla A, Andersen P, Doherty TM. The 6-kilodalton early secreted antigenic target-responsive, asymptomatic contacts of tuberculosis patients express elevated levels of interleukin-4 and reduced levels of gamma interferon. Infect Immun 2006; 74:2817-22. [PMID: 16622219 PMCID: PMC1459691 DOI: 10.1128/iai.74.5.2817-2822.2006] [Citation(s) in RCA: 33] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/20/2022] Open
Abstract
It is well known that the majority of healthy individuals exposed to Mycobacterium tuberculosis do not become clinically ill. We have previously shown that in recently exposed healthy contacts of tuberculosis (TB) patients, a strong immune response to the M. tuberculosis 6-kDa early secreted antigenic target (ESAT-6) virulence factor correlated with a higher risk of subsequent disease, although the mechanism was unclear at that time. Inspired by recent reports that elevated expression of interleukin-4 (IL-4) in health care workers exposed to M. tuberculosis also correlated with a higher risk of their subsequently developing disease, we examined expression of IL-4, its competitive antagonist IL-4delta2, and gamma interferon (IFN-gamma) in healthy household contacts of TB patients from Ethiopia. We then compared cytokine expression to their recognition of ESAT-6 (which is largely restricted to members of the tuberculosis complex and which serves as a reliable marker of infection) or to Ag85A (an antigen that is conserved among the mycobacteria and serves as a nonspecific control). Our study shows that in these recently exposed individuals, there is a correlation between a strong response to ESAT-6 and elevated expression of IL-4. Further, elevated expression of IL-4 is associated with lower expression of its antagonistic splice variant IL-4delta2 and with the Th1 cytokine IFN-gamma, suggesting that in these at-risk individuals, immunity is skewed away from a protective Th1 response, even before the development of clinical symptoms.
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Chang JS, Huggett JF, Dheda K, Kim LU, Zumla A, Rook GAW. Myobacterium tuberculosis induces selective up-regulation of TLRs in the mononuclear leukocytes of patients with active pulmonary tuberculosis. THE JOURNAL OF IMMUNOLOGY 2006; 176:3010-8. [PMID: 16493059 DOI: 10.4049/jimmunol.176.5.3010] [Citation(s) in RCA: 40] [Impact Index Per Article: 2.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 12/19/2022]
Abstract
Human and mouse studies indicate that TLRs are important in mycobacterial infections. We investigated TLR gene expression in fresh unstimulated blood and bronchoalveolar lavage from patients with pulmonary tuberculosis using a well-validated, real-time PCR. A human splice variant of TLR1, designated hsTLR1, was found in all donors tested. hsTLR1 mRNA lacks exon 2, which is a 77-bp region of the 5'-untranslated region, but contains the same coding sequence as TLR1. Compared with the matched controls, whole blood from patients had increased levels of mRNA encoding TLR2 (p = 0.0006), TLR1 (p = 0.004), hsTLR1 (p = 0.0003), TLR6 (p < 0.0001), and TLR4 (p = 0.0002). By contrast, expression of these TLRs was not increased in bronchoalveolar lavage. An increased level of hsTLR1 mRNA was found in both CD3- (p = 0.0078) and CD4+ cells (p = 0.028), resulting in an increased ratio of hsTLR1 mRNA to TLR1 and to TLR6 mRNA. An in vitro study in THP1 cells suggested that this relative increase in hsTLR1 might be attributable to a direct effect of mycobacterial components because it could be mimicked by mycobacterial preparations in the absence of IFN-gamma or T cells and by the TLR1/2 agonist Pam3CysK4. Half-life studies using blood from patients with pulmonary tuberculosis and THP1 cells exposed to Myobacterium tuberculosis in vitro showed p38 MAPK-independent stabilization of mRNAs encoding hsTLR1 and TLR1. We conclude that M. tuberculosis exerts direct effects on patterns of TLR expression, partly via changes in mRNA half-life. The significance of these changes in the pathogenesis of disease deserves further investigation.
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Affiliation(s)
- Jung-Su Chang
- Centre for Infectious Diseases and International Health, Royal Free and University College Medical School, London, United Kingdom
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Affiliation(s)
- Wing Wai Yew
- Grantham Hospital Tuberculosis and Chest Unit, 125 Wong Chuk Hang Road, Hong Kong, China.
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Affiliation(s)
- T Mark Doherty
- Department of Infectious Disease Immunology, Statens Serum Institute, Copenhagen, Denmark
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Rook GAW, Dheda K, Zumla A. Immune systems in developed and developing countries; implications for the design of vaccines that will work where BCG does not. Tuberculosis (Edinb) 2006; 86:152-62. [PMID: 16510309 DOI: 10.1016/j.tube.2006.01.018] [Citation(s) in RCA: 33] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/25/2005] [Accepted: 01/20/2006] [Indexed: 12/26/2022]
Abstract
New vaccine candidates for tuberculosis are beginning to enter clinical trials. In this review we discuss issues surrounding the design of these candidates, and the way they were screened in animal models. First, screening vaccines for their ability to attenuate inevitably fatal tuberculosis in immunologically naïve mice might be leading to the selection of inappropriate candidates. We need to screen vaccines for their ability to stop the development of progressive disease, since this is what they must achieve in man. A solution to this problem is proposed. Secondly, we point out that some mouse models of tuberculosis in laboratories in developing countries, where exposure to environmental mycobacteria is large, mimic neglected aspects of human disease more closely than do low-dose infections in hyper-susceptible immunologically naïve mice in the USA or Europe. We need to think more about geographical differences in immunological experience, and these mouse models can help us. Thirdly, we conclude that in developing countries where BCG fails this is not because there is too little Th1 response, but rather because the Th1 response is rendered ineffective and immunopathological by other subversive mechanisms, including IL-4 responses and inappropriate regulatory T cell function. Therefore, we suggest that vaccines that will work in those countries might need to have immunoregulatory properties that can switch off pre-existing subversive mechanisms, and block their development in the future. The development of such vaccines, that might work where BCG does not, will require a greater understanding of the roles of the many types of regulatory T cell in tuberculosis.
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Affiliation(s)
- Graham A W Rook
- Centre for Infectious Diseases and International Health, Windeyer Institute for Medical Sciences, University College London, UK.
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Rook GAW, Dheda K, Zumla A. Immune responses to tuberculosis in developing countries: implications for new vaccines. Nat Rev Immunol 2005; 5:661-7. [PMID: 16056257 DOI: 10.1038/nri1666] [Citation(s) in RCA: 116] [Impact Index Per Article: 6.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/09/2022]
Abstract
Tuberculosis is out of control in developing countries, where it is killing millions of people every year. In these areas, the present vaccine - Mycobacterium bovis bacillus Calmette-Guérin (BCG) - is failing. Progressive tuberculosis occurs because the potentially protective T helper 1 (T(H)1)-cell response is converted to an immunopathological response that fails to eliminate the bacteria. Here, we discuss the data indicating that the problem in developing countries is not a lack of adequate T(H)1-cell responses but, instead, an exaggerated tendency to switch to immunopathological responses. We propose that a successful vaccine needs to block this immunopathology, because it is not the quantity of T(H)1-cell activity that matters but, rather, its context.
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Affiliation(s)
- Graham A W Rook
- Centre for Infectious Diseases and International Health, Windeyer Institute for Medical Sciences, University College London, London W1T 4JF, UK.
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