All Title Author
Keywords Abstract


Autophagy Gene Variant IRGM ?261T Contributes to Protection from Tuberculosis Caused by Mycobacterium tuberculosis but Not by M. africanum Strains

DOI: 10.1371/journal.ppat.1000577

Full-Text   Cite this paper   Add to My Lib

Abstract:

The human immunity-related GTPase M (IRGM) has been shown to be critically involved in regulating autophagy as a means of disposing cytosolic cellular structures and of reducing the growth of intracellular pathogens in vitro. This includes Mycobacterium tuberculosis, which is in agreement with findings indicating that M. tuberculosis translocates from the phagolysosome into the cytosol of infected cells, where it becomes exposed to autophagy. To test whether IRGM plays a role in human infection, we studied IRGM gene variants in 2010 patients with pulmonary tuberculosis (TB) and 2346 unaffected controls. Mycobacterial clades were classified by spoligotyping, IS6110 fingerprinting and genotyping of the pks1/15 deletion. The IRGM genotype ?261TT was negatively associated with TB caused by M. tuberculosis (OR 0.66, CI 0.52–0.84, Pnominal 0.0009, Pcorrected 0.0045) and not with TB caused by M. africanum or M. bovis (OR 0.95, CI 0.70–1.30. P 0.8). Further stratification for mycobacterial clades revealed that the protective effect applied only to M. tuberculosis strains with a damaged pks1/15 gene which is characteristic for the Euro-American (EUAM) subgroup of M. tuberculosis (OR 0.63, CI 0.49–0.81, Pnominal 0.0004, Pcorrected 0.0019). Our results, including those of luciferase reporter gene assays with the IRGM variants ?261C and ?261T, suggest a role for IRGM and autophagy in protection of humans against natural infection with M. tuberculosis EUAM clades. Moreover, they support in vitro findings indicating that TB lineages capable of producing a distinct mycobacterial phenolic glycolipid that occurs exclusively in strains with an intact pks1/15 gene inhibit innate immune responses in which IRGM contributes to the control of autophagy. Finally, they raise the possibility that the increased frequency of the IRGM ?261TT genotype may have contributed to the establishment of M. africanum as a pathogen in the West African population.

References

[1]  Deretic V (2006) Autophagy as an immune defense mechanism. Curr Opin Immunol 18: 375–382.
[2]  Walker S, Chandra P, Manifava M, Axe E, Ktistakis NT (2008) Making autophagosomes: localized synthesis of phosphatidylinositol 3-phosphate holds the clue. Autophagy 4: 1093–1096.
[3]  Gutierrez MG, Master SS, Singh SB, Taylor GA, Colombo MI, et al. (2004) Autophagy is a defense mechanism inhibiting BCG and Mycobacterium tuberculosis survival in infected macrophages. Cell 119: 753–766.
[4]  Singh SB, Davis AS, Taylor GA, Deretic V (2006) Human IRGM induces autophagy to eliminate intracellular mycobacteria. Science 313: 1438–1441.
[5]  Butcher BA, Greene RI, Henry SC, Annecharico KL, Weinberg JB, et al. (2005) p47 GTPases regulate Toxoplasma gondii survival in activated macrophages. Infect Immun 73: 3278–3286.
[6]  Wang Y, Weiss LM, Orlofsky A (2009) Host cell autophagy is induced by Toxoplasma gondii and contributes to parasite growth. J Biol Chem 284: 1694–1701.
[7]  Bekpen C, Hunn JP, Rohde C, Parvanova I, Guethlein L, et al. (2005) The interferon-inducible p47 (IRG) GTPases in vertebrates: loss of the cell autonomous resistance mechanism in the human lineage. Genome Biol 6: R92.
[8]  Bekpen C, Marques-Bonet T, Alkan C, Antonacci F, Leogrande MB, et al. (2009) Death and resurrection of the human IRGM gene. PLoS Genet 5: e1000403. doi:10.1371/journal.pgen.1000403.
[9]  Parkes M, Barrett JC, Prescott NJ, Tremelling M, Anderson CA, et al. (2007) Sequence variants in the autophagy gene IRGM and multiple other replicating loci contribute to Crohn's disease susceptibility. Nat Genet 39: 830–832.
[10]  Massey DC, Parkes M (2007) Genome-wide association scanning highlights two autophagy genes, ATG16L1 and IRGM, as being significantly associated with Crohn's disease. Autophagy 3: 649–651.
[11]  McCarroll SA, Huett A, Kuballa P, Chilewski SD, Landry A, et al. (2008) Deletion polymorphism upstream of IRGM associated with altered IRGM expression and Crohn's disease. Nat Genet 40: 1107–1112.
[12]  Wirth T, Hildebrand F, Allix-Béguec C, W?lbeling F, Kubica T, et al. (2008) Origin, Spread and Demography of the Mycobacterium tuberculosis complex. PLoS Pathogens 4: e1000160. doi:10.1371/journal.ppat.1000160.
[13]  Herb F, Thye T, Niemann S, Browne EN, Chinbuah MA, et al. (2008) ALOX5 variants associated with susceptibility to human pulmonary tuberculosis. Hum Mol Genet 17: 1052–1060.
[14]  Gagneux S, Small PM (2007) Global phylogeography of Mycobacterium tuberculosis and implications for tuberculosis product development. Lancet Infect Dis 7: 328–337.
[15]  Intemann CD, Thye T, Sievertsen J, Owusu-Dabo E, Horstmann RD, et al. (2008) Genotyping of IRGM tetranucleotide promoter oligorepeats by fluorescence resonance energy transfer. BioTechniques 46: 58–60.
[16]  Altman DG, Bland JM (2003) Interaction revisited: the difference between two estimates. BMJ 326: 219.
[17]  Meyer CG, Scarisbrick G, Niemann S, Browne EN, Chinbuah MA, et al. (2008) Pulmonary tuberculosis: virulence of Mycobacterium africanum and relevance in HIV co-infection. Tuberculosis (Edinb) 88: 482–489.
[18]  Smith I (2003) Mycobacterium tuberculosis pathogenesis and molecular determinants of virulence. Clin Microbiol Rev 16: 463–496.
[19]  van der Wel N, Hava D, Houben D, Fluitsma D, van Zon M, et al. (2007) M. tuberculosis and M. leprae translocate from the phagolysosome to the cytosol in myeloid cells. Cell 129: 1287–1298.
[20]  Hagedorn M, Rohde KH, Russell DG, Soldati T (2009) Infection by tubercular mycobacteria is spread by nonlytic ejection from their amoeba hosts. Science 323: 1729–1733.
[21]  Lee BY, Clemens DL, Horwitz MA (2008) The metabolic activity of Mycobacterium tuberculosis, assessed by use of a novel inducible GFP expression system, correlates with its capacity to inhibit phagosomal maturation and acidification in human macrophages. Mol Microbiol 68: 1047–1060.
[22]  Nakagawa I, Amano A, Mizushima N, Yamamoto A, Yamaguchi H, et al. (2004) Autophagy defends cells against invading group A Streptococcus. Science 306: 1037–1040.
[23]  Ogawa M, Yoshimori T, Suzuki T, Sagara H, Mizushima N, et al. (2005) Escape of intracellular Shigella from autophagy. Science 307: 727–731.
[24]  Hayashi S, Okabe-Kado J, Honma Y, Kawajiri K (1995) Expression of Ah receptor (TCDD receptor) during human monocytic differentiation. Carcinogenesis 16: 1403–1409.
[25]  Platzer B, Richter S, Kneidinger D, Waltenberger D, Woisetschl?ger M, Strobl H (2009) Aryl hydrocarbon receptor activation inhibits in vitro differentiation of human monocytes and langerhans dendritic cells. J Immunol 183: 66–74.
[26]  MacMicking JD, Taylor GA, McKinney JD (2003) Immune control of tuberculosis by IFN-gamma-inducible LRG-47. Science 302: 654–659.
[27]  Reed MB, Domenech P, Manca C, Su H, Barczak AK, et al. (2004) A glycolipid of hypervirulent tuberculosis strains that inhibits the innate immune response. Nature 431: 84–87.
[28]  Tsenova L, Ellison E, Harbacheuski R, Moreira AL, Kurepina N, et al. (2005) Virulence of selected Mycobacterium tuberculosis clinical isolates in the rabbit model of meningitis is dependent on phenolic glycolipid produced by the bacilli. J Infect Dis 192: 98–106.
[29]  Sinsimer D, Huet G, Manca C, Tsenova L, Koo MS, et al. (2008) The phenolic glycolipid of Mycobacterium tuberculosis differentially modulates the early host cytokine response but does not in itself confer hypervirulence. Infect Immun 76: 3027–3036.
[30]  Thye T, Browne EN, Chinbuah MA, Gyapong J, Osei I, et al. (2006) No associations of human pulmonary tuberculosis with Sp110 variants. J Med Genet 43: e32.
[31]  Kamerbeek J, Schouls L, Kolk A, van Agterveld M, van Soolingen D, et al. (1997) Simultaneous detection and strain differentiation of Mycobacterium tuberculosis for diagnosis and epidemiology. J Clin Microbiol 35: 907–914.
[32]  van Embden JD, Cave MD, Crawford JT, Dale JW, Eisenach KD, et al. (1993) Strain identification of Mycobacterium tuberculosis by DNA fingerprinting: recommendations for a standardized methodology. J Clin Microbiol 31: 406–409.
[33]  Niemann S, Kubica T, Bange FC, Adjei O, Browne EN, et al. (2004) The species Mycobacterium africanum in the light of new molecular markers. J Clin Microbiol 42: 3958–3962.
[34]  Allix-Béguec C, Harmsen D, Weniger T, Supply P, Niemann S (2008) Evaluation and strategy for use of MIRU-VNTRplus, a multifunctional database for online analysis of genotyping data and phylogenetic identification of Mycobacterium tuberculosis complex isolates. J Clin Microbiol 46: 2692–2699.

Full-Text

comments powered by Disqus