MTOR and viral infectious disease: Downstream glucose capture, mTOR is a major sensor of environmental cues including immune signals and nutrient availability, and is also a major orchestrator of the glycolytic-lipogenic switch required for cell growth and proliferation; not only mTOR inhibition enhances iTreg differentiation (49, 50), but also mice carrying T cell-restricted mTOR deficiency show impaired T helper cell expansion, with enhanced Treg induction, in vitro and in vivo, in a model of viral infection (51).