Immunological and pathological studies in mice resistance to murine malaria

Abstract

Immunoblotting and immunofluorescent techniques were used to study immunological reaction between antibody in sera of experimental mice during acute infection and after recovery from P. berghei and P. chabaudi infections. Malarial parasite antigens of schizont infected erythorcytes were sonicated and solubilized in the presence of dithiothreitol before electropeparation on sodium dodecyl sulphate polyacrylamide gel. After electrotransfer to nitrocellulose paper, the separated protein components were reacted with individual serum of experimental mouse. Sera from P. berghei-chloroquin cured mice and P. chabaudi self-recovered mice showed several prominent reacting bands of polypeptides of P. berghei and P. chabaudi infected erythrocytes on immunnoblots respectively. For P.berghei chloroguin cured mice, their sara reacted with polypeptides in the range of molecular weights 73-180 Kd, whereas sora from P.chabaudi self-recovered mice showed reaction with polypeptides in the ranfe of less than 29 Kd-180 Kd. Particularly, the polypeptide with molecular weight 73 Kd was consistently reacted with immune sera from recovered mice. Whereas normal mouse sers showed no reaction with any polypeptides of P. berghei and P. chabaudi infected erythrocytes. The immune sera from recovered mice also did not reacted with protein components of normal mouse erythrocytes. This may indicate that immune sera of recovered mice contained antibodies direct against malaria derived antigens. By indirect immunofluorescent antibody technique, the antibody level was low at the early phase of infection and higher at recovery phsed. There were no significant alterations in livers, kidneys and spleens of recovered mice, except the mononuclear cells infilitation in the interstitial area fo kidney, periportal area of liver and hypertrophy and hyperplasia of white pulp with increasing plasma cell in red pulp of spleen Whereas macrophages containing malarial pigments as small graunles were observed during the patent infection in liver, kidney and spleen and larger forms during recovery phase. These findings may suggest that the elimination of malaria parasites was conferrred by both cellular and humoral immune responses.