Figure 1.

Representation of the distinct receptor systems employed by type I, type II and type III IFNs for signal transduction. Ligand engagement of these receptors initiates a signaling cascade that utilizes the receptor‐associated JAK kinases for receptor phosphorylation and subsequent STAT activation. ⁷ STATs activated following type I and type III IFN receptor engagement can drive expression of genes with either ISRE or GAS elements in their promoters, whereas signaling via the type II IFN receptor complex almost exclusively drives the expression of genes with GAS promoters elements. ²⁷