Neu^OT-I/OT-II TG mice are tolerant to OVA. C57BL/6 mice (A) or neu^OT-I/OT-II TG mice (C) were immunized twice (day 0 and day 14) intraperitoneally with STxB-OVA (0.25 nmol) or OVA (0.25 nmol) both mixed with αGalCer (1 μg) at day 0. One week later, splenocytes were harvested, semipurified with anti-CD8–coated magnetic beads, and stained with K^b-OVA_257-264 tetramer gated on CD8⁺ T cells or irrelevant K^b-VSV tetramer. (B) Mean tetramer levels in B6 mice immunized with STxB-OVA or OVA. These results are representative of 3 experiments with 4 mice per group. Values of P were calculated by the Mann-Whitney U test.