Figure 5

Induction of KIF20A-specific human CTLs from PBMCs of three HLA-A2-positive healthy donors. (A) KIF20A peptide-reactive CTLs generated from PBMCs of three HLA-A2-positive healthy donors effectively killed T2 cells (HLA-A2⁺, TAP deficient) pulsed with each peptide but not those unpulsed or pulsed with irrelevant and HLA-A2-restricted CTL epitopes of HIV. (B) Human CTLs exhibited cytotoxicity to the KIF20A⁺, HLA-A2⁺ human pancreatic cancer cell line PANC1 and to the colon cancer cell line CaCo-2, but not to KIF20A⁺, HLA-A2⁻ human pancreatic cancer cell line PK9. (C) The cytotoxicity of human CTLs was KIF20A specific. Those CTLs killed SKHep1/KIF20A, but not mock-transfected SKHep1 cells. Representative data are shown. (D) Human CTL responses were inhibited by anti-HLA-class I mAb (W6/32, IgG_2a) but not by anti-HLA-DR mAb (H-DR-1, IgG_2a). The target cells used were PANC-1cell (KIF20A⁺, HLA-A2⁺) and PK9 cell (KIF20A⁺, HLA-A2⁻). (Panels A–D) Representative data from one of the three donors with similar results are shown.