Abstract
Tryporaastogotes of three strains of Trypanosoma cruzi were isolated from the blood of infected mice employing lymphoprep for separation of the red blood cells and a column of DEAE cellulose for removal of white cells and platelets. An average recovery of 45 to 5 8 percent of actively motile, infective organisms, free of contaminating blood cells was obtained. Protein and carbohydrate assays of the separated organisms revealed significant differences between the Tulahuen, a reticulotropic strain, and the House 510 and House 11, two myotropic strains of this parasitic species. The present procedure should provide sufficient parasites for physiological and biochemical studies; it has also served to indicate particular strain characteristics which may aid in a taxonomic classification of these organisms.