Serum from Entamoeba histolytica-infected gerbils selectively suppresses T cell proliferation by inhibiting interleukin-2 production

J Infect Dis. 1999 Jun;179(6):1495-501. doi: 10.1086/314781.


Suppression of T and B cell responses during invasive amebiasis may be serum mediated. The mechanism of serum-mediated suppression of spleen cell lymphoproliferation from gerbils with amebic liver abscess was examined. Compared with uninfected gerbil serum (10%), serum samples collected at days 10, 30, and 60, but not at day 20 after infection, augmented both concanavalin A (Con A; T cell mitogen)- and lipopolysaccharide (LPS; B cell mitogen)-induced proliferation of homologous spleen cells. Only day 20 serum (>5%) inhibited Con A- but not LPS-induced proliferation of spleen cells from uninfected gerbils. The suppressive mechanism was independent of nitric oxide and prostaglandin but involved reduced interleukin (IL)-2 production. Addition of exogenous IL-2 reversed the suppressive effect of day 20 serum on Con A-stimulated proliferation. These results identify a mechanism whereby serum may contribute to transient suppression of T cell responses during Entamoeba histolytica infections.

Publication types

  • Research Support, Non-U.S. Gov't

MeSH terms

  • Animals
  • Concanavalin A / pharmacology
  • Gerbillinae
  • Immune Tolerance*
  • Interleukin-2 / biosynthesis*
  • Interleukin-2 / pharmacology
  • Liver Abscess, Amebic / blood*
  • Liver Abscess, Amebic / immunology*
  • Lymphocyte Activation
  • Spleen / cytology
  • Spleen / immunology
  • T-Lymphocytes / immunology*


  • Interleukin-2
  • Concanavalin A