Extended Data Figure 4.

Lipid-laden hepatocytes release linoleic acid and induce CD4⁺ T lymphocyte death via apoptosis.

a, Representative contour plots of ex vivo 7AAD/Annexin V staining of intrahepatic CD4⁺ T lymphocytes from MYC-ON mice fed with MCD or CTR. b, Representative phase-contrast images of primary hepatocytes from MYC-ON mice after MCD or CTR treatment. c-e, Isolated primary hepatocytes from MYC-ON mice on MCD or CTR were cocultured with isolated CD4⁺ T lymphocytes or splenocytes. Cell death levels were measured by flow cytometry. Mean ± SEM; n=4, one-way or two-way ANOVA. f, g, BODIPY 493/503 staining of CD4⁺ T lymphocytes in liver, spleen or blood from MYC-ON mice with MCD or CTR. Mean ± SEM; n=4, *p<0.05, two-way ANOVA. h,i, Identification of free fatty acids in hepatocyte conditioned medium by GC/MS. Mean ± SEM; n=3, *p<0.05, two-way ANOVA. j, Anti-CD3/28 beads-activated splenocytes were treated with different free fatty acids, and cell death level in CD4⁺ or CD8⁺ T lymphocytes were determined. Mean ± SEM; n=4, *p<0.05, two-way ANOVA. k-m, Dose-response curve and time course of linoleic acid-induced cell death in CD4⁺ or CD8⁺ T lymphocytes. n, caspase3/7 activity in CD4⁺ lymphocytes after linoleic acid treatment. Mean ± SEM; n=9, *p<0.05, Student’s t test. o, Dose-response curve of H₂O₂-induced cell death in CD4⁺ or CD8⁺ T lymphocytes. p, Uptake of linoleic acid by CD4⁺ and CD8⁺ T lymphocytes after incubation with 50 μM linoleic acid for 2 hrs. Mean ± SEM; n=6, *p<0.05. two-way ANOVA.