Innate immunity to amebic liver abscess is dependent on gamma interferon and nitric oxide in a murine model of disease

Evidence from in vitro studies suggests that gamma interferon (IFN-gamma) a nd nitric oxide (NO) are important in host defense against the protozoan pa rasite Entamoeba histolytica. We used SCID mice with targeted disruption of the IFN-gamma receptor gene and mice with targeted disruption of the gene encoding inducible NO synthase to show that IFN-gamma plays a role in the i nnate immunity to amebic liver abscess seen in SCID mice while NO is requir ed for control of amebic liver abscess in immunocompetent mice.