PLASMODIUM BERGHEI-INFECTION IN ISOGENIC F1(C57BI X DBA)-MICE .2. ANTIBODIES AND ANTIGENS IN SERUM

Abstract

Using the fluorescent antibody technique [FAT], it was possible to demonstrate antibodies in the sera of F1(C57B1 .times. DBA)-mice during the 1st wk of infection with P. berghei, strain K 173. These antibodies reached high titers during the 2nd and 3rd wk, but the animals died from the infection. Coincidently with the FAT-antibodies, plasmodial antigens were found in the sera of infected mice. The numbers of these antigens increased during the infection. Finally, up to 7 could be precipitated by using a double diffusion technique in cellulose acetate membranes. Since antibodies directed against these antigens were only found in immune animals, they must be different from the antibodies measured in the FAT. Comparison of the antigens found in the sera of infected animals with antigens prepared by physical desintegration of parasite material showed that in the sera, antigens appeared which were not demonstrated in the plasmodial extracts. If parasitic material was phagocytized by macrophages in cell cultures, antigens which were not found in the plasmodial extracts also appeared in the culture supernatant. Similar antigens were found if isolated parasites were allowed to degrade without the action of phagocytic cells.