Three CD8 + T cell epitopes had been identified from T. gondii proteins, based on their significant recognition by T cells from T. gondii seropositive HLA-A03 individuals [18] . A universal CD4 + T cell epitope, PADRE (AKFVAAWTLKAAA), was linked in sequence with the N-terminal end of each of the three different T. gondii CD8 + T cell epitopes: KSFKDILPK (SAG1 224-232 ), AML-TAFFLR (GRA6 164-172 ), RSFKDLLKK (GRA7 134-142 ). Also, these three epitopes were linked together with three alanines as the linker. The N-terminal end of each resulting CD4-CD8 peptide or polypeptide was extended by a lysine covalently linked to two molecules of the palmitic acid moiety. The lipopeptides (Lp) were named as LpKS9, LpAM9, LpRS9 and LpKS9-AM9-RS9. They are shown in Figure 1 .