Resolution of blood-stage malarial infections in CD8+ cell-deficient beta 2-m0/0 mice.
We utilized a definitive model of CD8+ T cell deficiency, the beta 2-microglobulin-deficient (beta 2-m0/0) mouse, to determine whether CD8+ T cells are required in the resolution of blood-stage malaria. In a parallel experiment, C57Bl/6 mice treated with anti-CD8 mAb showed significantly higher levels of parasitemia than untreated C57Bl/6 control mice at several points during the infection. This finding suggests some role for CD8+ cells in containing malaria. However, the beta 2-m0/0 mice, which are genetically blocked from expressing MHC class I or class Ib glycoproteins and therefore have < 2.5% of the normal number of CD8+ T cells, nevertheless resolved infections with three virulence variants of murine Plasmodium. The resolution of Plasmodium chabaudi adami, Plasmodium yoelii yoelii 17X, and Plasmodium chabaudi chabaudi AS infections by beta 2-m0/0 mice in the virtual absence of CD8+ cells demonstrates that these cells are not required to suppress murine malaria and that the suppression mechanism is not MHC class I restricted. The similarity of the time-course for resolution of infection in beta 2-m0/0 and intact control mice with all three subspecies of Plasmodium further supports the lack of a requirement for CD8+ T cells in the suppression of malarial parasitemia.
van der Heyde
H C
HC
Department of Medical Microbiology and Immunology, University of Wisconsin, Madison 53706.
Manning
D D
DD
Roopenian
D C
DC
Weidanz
W P
WP
D000818:Animals; D016827:CD8 Antigens / Q000032:analysis; D007111:Immunity, Cellular; D008212:Lymphocyte Depletion; D008288:Malaria / Q000276:immunology*; D051379:Mice; D016254:Mutagenesis, Insertional; D016788:Plasmodium chabaudi / Q000276:immunology / Q000472:pathogenicity; D010967:Plasmodium yoelii / Q000276:immunology / Q000472:pathogenicity; D013045:Species Specificity; D016176:T-Lymphocyte Subsets / Q000276:immunology*; D001613:beta 2-Microglobulin / Q000172:deficiency*
D016827:CD8 Antigens; D001613:beta 2-Microglobulin