Infection of the crab Pachygrapsus marmoratus with the rhizocephalan barnacle Sacculina carcini results in melanization of larvae in thoracic ganglia (Kuris et al., 2007) Antibody/factor that activates complement in serum of the non-host Raja radiata kills the tapeworm Acanthobothrium quadripartitum whereas larvae survive in serum of the normal host, Raja naevus (McVicar and Fletcher, 1970) Destruction of cercariae of avian schistosomes in the skin of mammals associated with a mixed Th1/Th2 lymphocyte cytokine response followed by more polarized Th2 response upon repeated exposures (Horak and Kolarova, 2005) Encapsulation of hymenopteran parasitoids by hemocytes of non-permissive insect hosts (Schmidt et al., 2001) Lysis of the trypanosome Trypanosoma brucei brucei by apolipoprotein L-1 in serum of humans who are refractory to this subspecies (Wheeler, 2010) .