CD8A and obesity disorder: Additionally, leptin-driven adiposity in mouse models of obesity promotes STAT3-facilitated FAO in intra-tumoral CD8+ T cells at the expense of glycolytic capability [28]; although this FAO shift is crucial for the formation of memory CD8+ T cells [29], the activation process is already compromised by diminished glycolysis, resulting in redundancy as FAO cannot sustain the energetic needs required for effector functions.