Cambridge MPD Parasitology Lecture Notes Parasitology Lecture Notes Cam. Neutralising antibody, e.g. malaria sporozoite, blocks cell receptor for entry into liver cells. Activated macrophages can be effective against many intracellular protozoa, e.g. Leishmania , Toxoplasma , Trypanosoma cruzi . T cells against parasite infected host cells, e.g. Plasmodium infected liver cell.
Helminths present a size problem to immune system, too big to phagocytose.
Hepatosplenic schistosomiasis, anti-egg immune responses initiate hepatic fibrosis. Anaphylactic shock following rupture of hydatid cyst. Parasites need time in host to complete complex development, to sexually reproduce, to ensure vector transmission. Some parasites with carnivore life-cycle need to outlive their hosts. Need to avoid immune elimination.