Persistence of Entamoeba histolytica infection in CBA mice owes to intestinal IL-4 production and inhibition of protective IFN-gamma

Mucosal Immunol. 2008 Mar;1(2):139-46. doi: 10.1038/mi.2007.18. Epub 2008 Jan 9.

Abstract

The mechanisms whereby certain mouse strains develop persistent intestinal infection with Entamoeba histolytica remain unclear. In this work, we characterized the kinetic pattern of cytokine responses during the course of natural infection in CBA mice and showed that intracecal amebic infection led to a rapid and sustained upregulation of Th2 (IL-4, IL-5, IL-13) and Th17 cytokine responses while Th1 cytokines, IL-12p35 and interferon (IFN)-gamma, were suppressed. Depletion of IL-4 cleared infection by 14 days post-challenge, and this clearance correlated with and was mediated by IFN-gamma. The protective role for IFN-gamma was not strain-specific, as 129 background IFN-gammaR knockout mice exhibited a higher infection rate than their wild-type littermates. These studies indicate that IL-4 plays a critical pathogenic role in the persistence of E. histolytica infection through suppression of protective IFN-gamma and provide a possible explanation for why certain humans spontaneously clear amebiasis while others progress to invasive disease.

Publication types

  • Research Support, N.I.H., Extramural
  • Research Support, Non-U.S. Gov't

MeSH terms

  • Animals
  • Dysentery, Amebic / genetics
  • Dysentery, Amebic / immunology*
  • Entamoeba histolytica / immunology*
  • Entamoebiasis / genetics
  • Entamoebiasis / immunology*
  • Humans
  • Interferon-gamma / genetics
  • Interferon-gamma / immunology*
  • Interleukin-12 Subunit p35 / genetics
  • Interleukin-12 Subunit p35 / immunology
  • Interleukin-13 / genetics
  • Interleukin-13 / immunology
  • Interleukin-4 / genetics
  • Interleukin-4 / immunology*
  • Interleukin-5 / genetics
  • Interleukin-5 / immunology
  • Male
  • Mice
  • Mice, Inbred CBA
  • Mice, Knockout
  • Th1 Cells / immunology
  • Th2 Cells / immunology

Substances

  • Il12a protein, mouse
  • Interleukin-12 Subunit p35
  • Interleukin-13
  • Interleukin-5
  • Interleukin-4
  • Interferon-gamma