Table 1. Differential equation variables and initial values.

Parameter	Definition	Initial Value	Reference
Intermediate affinity IL-15R variables
Ntot	total NK cell number	25,000	[23]
Vm	cell culture media volume	200 µL
Rs	free surface IL-15Rβγ	800	[14]
Re	endosomal free IL-15Rβγ	0
Cs	surface IL-15/IL-15Rβγ complex	0
Ce	endosomal IL-15/IL-15Rβγ complex	0
L	media intermediate affinity ligand concentration	variable, mole/L
Le	endosomal intermediate affinity ligand concentration	0 mole/L
High affinity IL-15R variables
Cs′	surface IL-15/IL-15Rαβγ complex	0
Ce′	endosomal IL-15/IL-15Rαβγ complex	0
Λs	surface high affinity ligand	0
Λe	endosomal high affinity ligand	0

Model state variables were used to analyze IL-15R binding, trafficking, and synthesis. The high affinity binding model introduces additional variables as a result of the inclusion IL-15Rα.