Cultivation of Toxoplasma in Embryonated Egg. An Antigen Derived from Choriolallantoic Membrane

Summary Inoculation of embryonated eggs with toxoplasma resulted in a generalized parasitic disease of this host with a fatal termination. The agent could be maintained by serial passage of embryo brain. Chorioallantoic membranes from infected eggs contained a stable, specific soluble antigen which fixed complement with toxoplasma immune animal serum. Human sera from both proven and suspected cases of toxoplasmosis which were known to contain neutralizing antibody against the parasite also fixed complement with chorioallantoic membrane antigen.