CHARACTERIZATION OF HEMOZOIN FROM LIVER AND SPLEEN OF MICE INFECTED WITH PLASMODIUM-YOELLI, A RODENT MALARIA PARASITE

A non-enzymatic protocol for the purification of hemozoin, the malaria pigment, accumulated in the liver and spleen of mice infected with Plasmodium yoelii has been developed. The procedure, including repeated extraction with 2.5% SDS followed by washings with methanol, chloroform and bicarbonate buffer, completely removes the non-hemozoin heme and other non-covalently adhered biomolecules. The purified hemozoin contains 94-98% ferriprotoporphyrin IX as quantitated by spectral analysis. A parasitemia-dependent accumulation of hemozoin was demonstrated which was more marked in the liver than in the spleen. Though, major fraction of the pigment was recovered in 1,000 g particulate fraction, a significant quantity of hemozoin was associated with other membrane fractions. Elemental composition, Fourier Transformed Infrared spectroscopy, and FAB mass analysis established molecular characteristics of hemozoin isolated from the tissues as the polymer of heme, similar to that characterized earlier from the food vacuoles of malaria parasite.