SURVIVAL STRATEGIES OF ENTAMOEBA-HISTOLYTICA - MODULATION OF CELL-MEDIATED IMMUNE-RESPONSES

Tissue invasion and disease associated with the protozoan Entamoeba hi stolytica has long been connected with suppression of host cellular im munity. Dampening of the host's defences may facilitate survival of am oebae in extraintestinal sites and development of the characteristic a moebic abscesses. In recent years, several studies have begun to clari fy, at the cellular level, the specific effects E. histolytica has on immune cell accessory and effector cell functions. Here, Darren Campbe ll and Kris Chadee discuss the parasite's multiple modulatory effects on macrophages and T cells and how this manipulation of immune defence s may enable the parasite to remain viable in the host. They suggest t he putative amoebic molecules involved and potential modulation by the cytokines: interleukins IL-4 and IL-10 and transforming growth factor -beta.