T cell reactivity of defined peptides from a major Plasmodium falciparum vaccine candidate: the Pf155/RESA antigen.
Several immunodominant B-cell epitopes of the P. falciparum antigen blood stage Pf155/RESA, a major vaccine candidate antigen, are located in the molecular regions containing amino acid repeats. We started to map Pf155/RESA for T cell reactive epitopes. For this purpose, short synthetic peptides corresponding to the 3'- and 5' repeat regions of the molecule as well as to non-repeated sequences outside these regions were prepared. T cells from P. falciparum primed donors from two highly endemic areas of Africa were tested for their responsiveness to the peptides by thymidine incorporation and/or interferon gamma (IFN-gamma) release. There was a considerable variation in the response to the different peptides. However, the strongest and most frequent responses were seen with a few peptides from the 3'- and 5'-repeat regions. Thus, the immunodominant B cell epitope regions of Pf155/RESA, contain several T cell epitopes. Since the repeat regions are known to be conserved in different P. falciparum strains, the T cell epitopes reported here may be suitable constituents of a P. falciparum subunit vaccine.
Troye-Blomberg
M
M
Department of Immunology, University of Stockholm, Sweden.
Kabilan
L
L
Riley
E M
EM
Ortlund
J
J
Andersson
G
G
Perlmann
H
H
Olerup
O
O
Högh
B
B
Petersen
E
E
Snow
R W
RW
D000818:Animals; D000953:Antigens, Protozoan / Q000032:analysis / Q000276:immunology*; D006801:Humans; D007108:Immune Tolerance; D010446:Peptide Fragments / Q000276:immunology; D010963:Plasmodium falciparum / Q000276:immunology*; D013601:T-Lymphocytes / Q000276:immunology*; D014614:Vaccines, Synthetic / Q000276:immunology
D000953:Antigens, Protozoan; D010446:Peptide Fragments; D014614:Vaccines, Synthetic