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Allele-specific induction of IL-1β expression by C/EBPβ and PU.1 contributes to increased tuberculosis susceptibility.

Zhang G, Zhou B, Li S, Yue J, Yang H, Wen Y, Zhan S, Wang W, Liao M, Zhang M, Zeng G, Feng CG, Sassetti CM, Chen X - PLoS Pathog. (2014)

Bottom Line: Mycobacterium tuberculosis infection is associated with a spectrum of clinical outcomes, from long-term latent infection to different manifestations of progressive disease.Thus, the ultimate contribution of individual inflammatory pathways to the outcome of M. tuberculosis infection remains ambiguous.In this study, we identified a naturally-occurring polymorphism in the human IL1B promoter region, which alters the association of the C/EBPβ and PU.1 transcription factors and controls Mtb-induced IL-1β production.

View Article: PubMed Central - PubMed

Affiliation: Guangdong Key Lab of Emerging Infectious Diseases, Guangdong Medical College, Shenzhen, China; Shenzhen Key Lab of Infection and Immunity, Shenzhen Third People's Hospital, Guangdong Medical College, Shenzhen, China.

ABSTRACT
Mycobacterium tuberculosis infection is associated with a spectrum of clinical outcomes, from long-term latent infection to different manifestations of progressive disease. Pro-inflammatory pathways, such as those controlled by IL-1β, have the contrasting potential both to prevent disease by restricting bacterial replication, and to promote disease by inflicting tissue damage. Thus, the ultimate contribution of individual inflammatory pathways to the outcome of M. tuberculosis infection remains ambiguous. In this study, we identified a naturally-occurring polymorphism in the human IL1B promoter region, which alters the association of the C/EBPβ and PU.1 transcription factors and controls Mtb-induced IL-1β production. The high-IL-1β expressing genotype was associated with the development of active tuberculosis, the severity of pulmonary disease and poor treatment outcome in TB patients. Higher IL-1β expression did not suppress the activity of IFN-γ-producing T cells, but instead correlated with neutrophil accumulation in the lung. These observations support a specific role for IL-1β and granulocytic inflammation as a driver of TB disease progression in humans, and suggest novel strategies for the prevention and treatment of tuberculosis.

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Allele-specific effects of rs1143627 are mediated through PU.1 and C/EBPβ.(A) IL1B promoter luciferase reporter plasmids carrying rs1143627 T or C allele were transfected into HeLa cells, with or without co-transfecting PU.1- or C/EBPβ-expressing plasmids. Luciferase activities of HeLa cells were determined and normalized to Renillla luciferase activities. (B) HeLa cells cotransfected with the T-allele IL1B promoter luciferase reporter plasmids, PU.1- and C/EBP-β- expressing plasmids were infected with PU.1, C/EBPβ, or control siRNA-carrying lentiviral vector constructs. Luciferase activities of HeLa cells were determined and normalized to Renillla luciferase activities. Differences between groups were compared with the ANOVA/Newman-Keuls multiple comparison test. (C) Western-blotting assay shows the expression of PU.1 or C/EBPβ after transfection or siRNA knockdown using monoclonal antibodies against PU.1 and C/EBPβ. **, p<0.01, ***, p<0.001.
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ppat-1004426-g006: Allele-specific effects of rs1143627 are mediated through PU.1 and C/EBPβ.(A) IL1B promoter luciferase reporter plasmids carrying rs1143627 T or C allele were transfected into HeLa cells, with or without co-transfecting PU.1- or C/EBPβ-expressing plasmids. Luciferase activities of HeLa cells were determined and normalized to Renillla luciferase activities. (B) HeLa cells cotransfected with the T-allele IL1B promoter luciferase reporter plasmids, PU.1- and C/EBP-β- expressing plasmids were infected with PU.1, C/EBPβ, or control siRNA-carrying lentiviral vector constructs. Luciferase activities of HeLa cells were determined and normalized to Renillla luciferase activities. Differences between groups were compared with the ANOVA/Newman-Keuls multiple comparison test. (C) Western-blotting assay shows the expression of PU.1 or C/EBPβ after transfection or siRNA knockdown using monoclonal antibodies against PU.1 and C/EBPβ. **, p<0.01, ***, p<0.001.

Mentions: To assess the role of PU.1 and C/EBPβ in Mtb-induced IL1B transcription, we investigated whether ectopic PU.1 and C/EBPβ expression affects IL1B promoter activity in HeLa cells. As shown in Fig. 6A, transfection of a reporter plasmid containing a 1371 bp fragment of the human IL1B promoter (−1292 to +79) produced very low luciferase levels. However, cotransfection of the IL1B promoter plasmid with PU.1 or C/EBPβ expression plasmids significantly enhanced luciferase levels, and cotransfection of all three plasmids further increased promoter activity (Fig. 6A). Expression levels of PU.1 and C/EBPβ were similar when transfected either individually or in combination (Fig. 6C).


Allele-specific induction of IL-1β expression by C/EBPβ and PU.1 contributes to increased tuberculosis susceptibility.

Zhang G, Zhou B, Li S, Yue J, Yang H, Wen Y, Zhan S, Wang W, Liao M, Zhang M, Zeng G, Feng CG, Sassetti CM, Chen X - PLoS Pathog. (2014)

Allele-specific effects of rs1143627 are mediated through PU.1 and C/EBPβ.(A) IL1B promoter luciferase reporter plasmids carrying rs1143627 T or C allele were transfected into HeLa cells, with or without co-transfecting PU.1- or C/EBPβ-expressing plasmids. Luciferase activities of HeLa cells were determined and normalized to Renillla luciferase activities. (B) HeLa cells cotransfected with the T-allele IL1B promoter luciferase reporter plasmids, PU.1- and C/EBP-β- expressing plasmids were infected with PU.1, C/EBPβ, or control siRNA-carrying lentiviral vector constructs. Luciferase activities of HeLa cells were determined and normalized to Renillla luciferase activities. Differences between groups were compared with the ANOVA/Newman-Keuls multiple comparison test. (C) Western-blotting assay shows the expression of PU.1 or C/EBPβ after transfection or siRNA knockdown using monoclonal antibodies against PU.1 and C/EBPβ. **, p<0.01, ***, p<0.001.
© Copyright Policy
Related In: Results  -  Collection

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Show All Figures
getmorefigures.php?uid=PMC4199770&req=5

ppat-1004426-g006: Allele-specific effects of rs1143627 are mediated through PU.1 and C/EBPβ.(A) IL1B promoter luciferase reporter plasmids carrying rs1143627 T or C allele were transfected into HeLa cells, with or without co-transfecting PU.1- or C/EBPβ-expressing plasmids. Luciferase activities of HeLa cells were determined and normalized to Renillla luciferase activities. (B) HeLa cells cotransfected with the T-allele IL1B promoter luciferase reporter plasmids, PU.1- and C/EBP-β- expressing plasmids were infected with PU.1, C/EBPβ, or control siRNA-carrying lentiviral vector constructs. Luciferase activities of HeLa cells were determined and normalized to Renillla luciferase activities. Differences between groups were compared with the ANOVA/Newman-Keuls multiple comparison test. (C) Western-blotting assay shows the expression of PU.1 or C/EBPβ after transfection or siRNA knockdown using monoclonal antibodies against PU.1 and C/EBPβ. **, p<0.01, ***, p<0.001.
Mentions: To assess the role of PU.1 and C/EBPβ in Mtb-induced IL1B transcription, we investigated whether ectopic PU.1 and C/EBPβ expression affects IL1B promoter activity in HeLa cells. As shown in Fig. 6A, transfection of a reporter plasmid containing a 1371 bp fragment of the human IL1B promoter (−1292 to +79) produced very low luciferase levels. However, cotransfection of the IL1B promoter plasmid with PU.1 or C/EBPβ expression plasmids significantly enhanced luciferase levels, and cotransfection of all three plasmids further increased promoter activity (Fig. 6A). Expression levels of PU.1 and C/EBPβ were similar when transfected either individually or in combination (Fig. 6C).

Bottom Line: Mycobacterium tuberculosis infection is associated with a spectrum of clinical outcomes, from long-term latent infection to different manifestations of progressive disease.Thus, the ultimate contribution of individual inflammatory pathways to the outcome of M. tuberculosis infection remains ambiguous.In this study, we identified a naturally-occurring polymorphism in the human IL1B promoter region, which alters the association of the C/EBPβ and PU.1 transcription factors and controls Mtb-induced IL-1β production.

View Article: PubMed Central - PubMed

Affiliation: Guangdong Key Lab of Emerging Infectious Diseases, Guangdong Medical College, Shenzhen, China; Shenzhen Key Lab of Infection and Immunity, Shenzhen Third People's Hospital, Guangdong Medical College, Shenzhen, China.

ABSTRACT
Mycobacterium tuberculosis infection is associated with a spectrum of clinical outcomes, from long-term latent infection to different manifestations of progressive disease. Pro-inflammatory pathways, such as those controlled by IL-1β, have the contrasting potential both to prevent disease by restricting bacterial replication, and to promote disease by inflicting tissue damage. Thus, the ultimate contribution of individual inflammatory pathways to the outcome of M. tuberculosis infection remains ambiguous. In this study, we identified a naturally-occurring polymorphism in the human IL1B promoter region, which alters the association of the C/EBPβ and PU.1 transcription factors and controls Mtb-induced IL-1β production. The high-IL-1β expressing genotype was associated with the development of active tuberculosis, the severity of pulmonary disease and poor treatment outcome in TB patients. Higher IL-1β expression did not suppress the activity of IFN-γ-producing T cells, but instead correlated with neutrophil accumulation in the lung. These observations support a specific role for IL-1β and granulocytic inflammation as a driver of TB disease progression in humans, and suggest novel strategies for the prevention and treatment of tuberculosis.

Show MeSH
Related in: MedlinePlus