Fecal Microbiota Composition Differs Between Children With β-Cell Autoimmunity and Those Without

  1. Outi Vaarala2
  1. 1Department of Medical Microbiology, University Medical Center Groningen and University of Groningen, Groningen, the Netherlands
  2. 2Immune Response Unit, Department of Vaccination and Immune Protection, National Institute for Health and Welfare, Helsinki, Finland
  3. 3Children’s Hospital, University of Helsinki and Helsinki University Central Hospital, Helsinki, Finland
  4. 4Folkhälsan Research Center, Helsinki, Finland
  5. 5Department of Pediatrics, Tampere University Hospital, Tampere, Finland
  6. 6Immunogenetics Laboratory, University of Turku, Turku, Finland and Department of Clinical Immunology, University of Eastern Finland, Kuopio, Finland
  1. Corresponding author: Outi Vaarala, outi.vaarala{at}thl.fi
  1. M.C.d.G. and K.L. contributed equally to this study.

Abstract

The role of the intestinal microbiota as a regulator of autoimmune diabetes in animal models is well-established, but data on human type 1 diabetes are tentative and based on studies including only a few study subjects. To exclude secondary effects of diabetes and HLA risk genotype on gut microbiota, we compared the intestinal microbiota composition in children with at least two diabetes-associated autoantibodies (n = 18) with autoantibody-negative children matched for age, sex, early feeding history, and HLA risk genotype using pyrosequencing. Principal component analysis indicated that a low abundance of lactate-producing and butyrate-producing species was associated with β-cell autoimmunity. In addition, a dearth of the two most dominant Bifidobacterium species, Bifidobacterium adolescentis and Bifidobacterium pseudocatenulatum, and an increased abundance of the Bacteroides genus were observed in the children with β-cell autoimmunity. We did not find increased fecal calprotectin or IgA as marker of inflammation in children with β-cell autoimmunity. Functional studies related to the observed alterations in the gut microbiome are warranted because the low abundance of bifidobacteria and butyrate-producing species could adversely affect the intestinal epithelial barrier function and inflammation, whereas the apparent importance of the Bacteroides genus in development of type 1 diabetes is insufficiently understood.

  • Received May 2, 2012.
  • Accepted November 2, 2012.

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