Figure 3. L-Lactate Depletes Post-GAPDH Glycolytic Intermediates.

(A and B) Tconvs were co-stimulated with CD3ε/CD28 mAb-coated beads and cultured in low-glucose medium (30 mg × dL⁻¹) ± 20 mM NaCl or Na L-lactate, with either 0.5 μM ionomycin, 1 μM of the GAPDH inhibitor (GAPDHi) heptelidic acid, or vehicle controls. After 3 days, proliferation was analyzed via CFSE dilution. (A) shows representative and (B) quantitative data pooled from three independent experiments (paired one-way ANOVA).

(C) Lactate inhibits GAPDH and PGDH, although oxalate blocks pyruvate kinase.

(D and E) Tconvs were co-stimulated with CD3ε/CD28 mAb-coated beads and cultured in low-glucose medium (30 mg × dL⁻¹) in serine/glycine-free media ± 20 mM NaCl or Na L-lactate, with either 0.4 mM serine or 1 mM Na oxalate or vehicle controls. After 3 days, proliferation was analyzed via CFSE dilution. (D) shows representative and (E) quantitative data pooled from four independent experiments (paired one-way ANOVA). *p < 0.05, **p < 0.01, and ***p < 0.001. Error bars indicate SEM.