Cytotoxic T cells recognize a peptide from the circumsporozoite protein on malaria-infected hepatocytes.
Irradiated malaria sporozoites can induce CD8+ T cells that are required for protection against infection. However, the parasite antigens targeted by this immune response are unknown. We have discovered a 16-amino acid epitope from the Plasmodium yoelii circumsporozoite (CS) protein that is recognized by cytotoxic T cells from immune mice. Lymphocytes stimulated with this peptide can kill P. yoelii liver stage parasites in vitro in an MHC-restricted, antigen-specific manner. Thus, epitopes from the CS protein are presented on the surface of infected hepatocytes and can be targets for T cells, even though intact CS protein has not been detected on the surface of the infected hepatocyte. A vaccine that induced CTL to parasite antigens might protect humans against malaria by eliminating liver stage parasites.
Weiss
W R
WR
Infectious Disease Department, Naval Medical Research Institute, Bethesda, Maryland 20814.
Mellouk
S
S
Houghten
R A
RA
Sedegah
M
M
Kumar
S
S
Good
M F
MF
Berzofsky
J A
JA
Miller
L H
LH
Hoffman
S L
SL
D000818:Animals; D000939:Epitopes / Q000032:analysis; D005260:Female; D007114:Immunization; D008099:Liver / Q000276:immunology / Q000469:parasitology*; D008288:Malaria / Q000276:immunology; D051379:Mice; D008807:Mice, Inbred BALB C; D010446:Peptide Fragments / Q000276:immunology*; D010967:Plasmodium yoelii / Q000276:immunology*; D015800:Protozoan Proteins / Q000276:immunology*; D013602:T-Lymphocytes, Cytotoxic / Q000276:immunology*; D014612:Vaccines / Q000276:immunology
D000939:Epitopes; D010446:Peptide Fragments; D015800:Protozoan Proteins; D014612:Vaccines