Day 7 allogeneic T cells increase FA oxidation ex vivo and in vivo. (A) T cells were purified by magnetic separation from naïve donors or day 7 allogeneic recipients (GVHD), incubated with 3H-palmitate for 6 hours (unstimulated), and supernatants assayed for production of 3H2O as detailed in Methods. Analysis was performed in triplicate with pooled samples and represent >3 independent experiments. Stimulated samples were incubated with 3H-palmitate for 16 hours on anti-CD3, anti-CD28–coated plates. (B) Glutamate labeled in the 4,5 position with 13C (M2 glutamate) was compared with total 13C-labeled glutamate as described in Methods. *P = .02, ***P < .005.