Transduction of CD8+ T cells

For transfections, 293T cells were seeded into 96-mm dishes at a density of 5 × 10⁶ cells 1 day before transfection. Cells were transfected with empty- or FABP1-pMSCV-Ametrine–encoding vector using the CalPhos Mammalian Transfection Kit (Takara). Viral supernatant was harvested after 48 hours by filtration (0.22 μm; Millipore), and 0.5 ml of fresh filtered virus supernatant was transferred to 24-well plates coated with RetroNectin (20 μg/ml; Takara). Naïve CD8⁺ T cells from spleen and lymph nodes from naïve C57BL/6 (CD45.1.2⁺) or Fabp1^−/− (CD45.2⁺) mice were enriched, and 1 × 10⁶ cells were plated in 24-well plates (Thermo Fisher Scientific) precoated with anti-CD3 (clone 2C11) and anti-CD28 (37.51) (5 μg/ml; eBioscience). In vitro activated CD8⁺ T cells were transferred to 24-well plates containing viral supernatant and expanded for a further 3 days in the presence of IL-2 (25 U/ml; PeproTech). Transduction efficacy was determined by Ametrine expression, and 2.5 × 10⁵ transduced WT and Fabp1^−/− cells were mixed 1:1 and transferred intravenously into C57BL/6 (CD45.1⁺) mice.