Intestinal CD103+ dendritic cells are key players in the innate immune control of Cryptosporidium parvum infection in neonatal mice

PLoS Pathog. 2013;9(12):e1003801. doi: 10.1371/journal.ppat.1003801. Epub 2013 Dec 19.

Abstract

Cryptosporidium parvum is a zoonotic protozoan parasite found worldwide, that develops only in the gastrointestinal epithelium and causes profuse diarrhea. Using a mouse model of C. parvum infection, we demonstrated by conditional depletion of CD11c+ cells that these cells are essential for the control of the infection both in neonates and adults. Neonates are highly susceptible to C. parvum but the infection is self-limited, whereas adults are resistant unless immunocompromised. We investigated the contribution of DC to the age-dependent susceptibility to infection. We found that neonates presented a marked deficit in intestinal CD103+ DC during the first weeks of life, before weaning, due to weak production of chemokines by neonatal intestinal epithelial cells (IEC). Increasing the number of intestinal CD103+ DC in neonates by administering FLT3-L significantly reduced susceptibility to the infection. During infections in neonates, the clearance of the parasite was preceded by a rapid recruitment of CD103+ DC mediated by CXCR3-binding chemokines produced by IEC in response to IFNγ. In addition to this key role in CD103+ DC recruitment, IFNγ is known to inhibit intracellular parasite development. We demonstrated that during neonatal infection CD103+ DC produce IL-12 and IFNγ in the lamina propria and the draining lymph nodes. Thus, CD103+DC are key players in the innate immune control of C. parvum infection in the intestinal epithelium. The relative paucity of CD103+ DC in the neonatal intestine contributes to the high susceptibility to intestinal infection.

Publication types

  • Research Support, Non-U.S. Gov't

MeSH terms

  • Age Factors
  • Animals
  • Animals, Newborn
  • Antigens, CD / metabolism*
  • Cattle
  • Child
  • Cryptosporidiosis / immunology*
  • Cryptosporidium parvum / immunology*
  • Dendritic Cells / metabolism
  • Dendritic Cells / physiology*
  • Humans
  • Immunity, Innate*
  • Integrin alpha Chains / metabolism*
  • Intestines / cytology
  • Intestines / immunology*
  • Mice
  • Mice, Inbred C57BL
  • Mice, Knockout

Substances

  • Antigens, CD
  • Integrin alpha Chains
  • alpha E integrins

Grants and funding

This work was supported by INRA (http://www.international.inra.fr/) and by a grant from ICSA, the French Carnot Institute for Animal Health (http://www.ic-sante-animale.org/index.php/fr/). Part of this work was also supported by the EMMA service under the EU contract Grant Agreement Number 227490 of the EC FP7 Capacities Specific Programme (http://www.emmanet.org/projects/emmaservice.php). LL and WG have PhD fellowships from INRA and the Région Centre (http://www.regioncentre.fr/accueil/les-services-en-ligne/la-region-centre-vous-aide/recherche-et-innovation/bourses-doctorales.html). The funders had no role in study design, data collection and analysis, decision to publish, or preparation of the manuscript.