Fig 1. Schematic of the final model structure, linking the endotoxin concentration-time course (C_ETX) to induction of tumor necrosis factor alpha (C_TNF-α) through a sigmoidal Emax relationship, and to development of tolerance (EC₅₀) through an Emax relationship.

Both time-courses stimulate the induction of interleukin-6 (C_IL-6) with linear relationships to endotoxin and tumor necrosis factor alpha. For parameter description and estimates, see Table 2.