A rapid and simple method of purification of Toxoplasma gondii trophozoites originating from tissue culture for use in the indirect immunofluorescent antibody test.

A simple and convenient purification method for Toxoplasma trophozoites from tissue culture cells by density centrifugation is described. Separation of cells treated with formaldehyde is achieved by means of a Percoll solution with a density of 1.056 g/ml permitting removal of more than 99% of the cells and cell debris from the tissue culture. Thus highly purified trophozoites of Toxoplasma gondii raised in tissue cultures become available for serological tests, particularly for the indirect immunofluorescent antibody test.