. Author manuscript; available in PMC: 2022 Sep 1.

Published in final edited form as: Curr Opin Rheumatol. 2021 Sep 1;33(5):371–377. doi: 10.1097/BOR.0000000000000816

Table 1.

IFN signaling by type.

IFN type	Specific IFNs	Receptor	JAK	STAT
Type I IFN	alpha (α), beta (β), epsilon (ε), kappa (κ), omega (ω)	IFNAR1	TYK2	STAT1-STAT2 heterodimer
Type I IFN	alpha (α), beta (β), epsilon (ε), kappa (κ), omega (ω)	IFNAR2	JAK1	STAT1-STAT2 heterodimer
Type II IFN	gamma (γ)	IFNGR1	JAK2	STAT1-STAT1 homodimer
Type II IFN	gamma (γ)	IFNGR2	JAK1	STAT1-STAT1 homodimer
Type III IFN	lambda (λ)	IL10R2	TYK2	STAT1-STAT2 heterodimer
Type III IFN	lambda (λ)	IFNLR1	JAK1	STAT1-STAT2 heterodimer

JAK : Janus kinase, STAT: Signal Transducers and Activators of Transcription

From left to write, when type I, II, or III binds its receptor, its respective Janus kinases (JAKs) activate by phosphorylation. That causes the respective Signal Transducers and Activators of Transcription (STAT) to phosphorylate and dimerize.