Immune development in jejunal mucosa after colonization with selected commensal gut bacteria: a study in germ-free pigs

Vet Immunol Immunopathol. 2007 Oct 15;119(3-4):243-53. doi: 10.1016/j.vetimm.2007.05.022. Epub 2007 Jun 19.


The immunological structure of the porcine jejunal lamina propria in germ-free piglets was compared with that of their counterparts associated with two strains of commensal Escherichia coli, A0 34/86 serotype O83:K24:H31 and the O86 E. coli strain, up to 20 days post-colonization. In the antigen-presenting compartment, both dendritic cells (DC) and cells expressing CD163, probably macrophages were investigated. In addition we also assessed the number of CD2+/CD3+ (T) cells. In contrast to some previous reports, we show a total lack of both DC and T cells for germ-free animals in the diffuse lymphoid tissue of villi and crypts of the jejunum. Association with either strain of commensal E. coli had a profound effect on the immune structure and resulted in extensive recruitment of DC to the lamina propria and of T cells to epithelium and lamina propria. The data suggest that the earliest immigrant cells were monocytes, which soon acquired the phenotype of mucosal DC. T cells migrated in at a slightly slower rate. Nevertheless, the response could be extremely rapid: within 3 days of colonization with O83, the magnitude of this response was comparable to that observed 20 days post-colonization.

Publication types

  • Research Support, Non-U.S. Gov't

MeSH terms

  • Animals
  • Antigens, CD / metabolism
  • Antigens, Differentiation, Myelomonocytic / metabolism
  • CD3 Complex / metabolism
  • Escherichia coli / immunology*
  • Escherichia coli / physiology
  • Germ-Free Life*
  • Histocompatibility Antigens
  • Intestinal Mucosa / immunology*
  • Intestinal Mucosa / microbiology*
  • Jejunum / cytology
  • Jejunum / immunology*
  • Jejunum / microbiology*
  • Receptors, Cell Surface / metabolism
  • Receptors, IgG / metabolism
  • Swine / immunology*
  • Swine / microbiology*


  • Antigens, CD
  • Antigens, Differentiation, Myelomonocytic
  • CD163 antigen
  • CD3 Complex
  • Histocompatibility Antigens
  • Receptors, Cell Surface
  • Receptors, IgG