IL-2 signaling pathway (WP49)

IL-2 is a multifunctional cytokine with pleiotropic effects on several cells of the immune system. IL-2 was originally discovered as a T cell growth factor, but it was also found to have actions related to B cell proliferation, and cytolytic activity of natural killer cells. IL-2 also activates lymphokine activated killer cells. In contrast to its proliferative effects, IL-2 also has potent activity in a process known as activation-induced cell death. More recently, IL-2 was shown to promote tolerance through its effects on regulatory T cell development. IL-2 clinically has anti-cancer effects as well as utility in supporting T cell numbers in HIV/AIDS. There are three classes of IL-2 receptors, binding IL-2 with low, intermediate, or high-affinity. The low affinity receptor (IL-2Rα alone) is not functional; signaling by IL-2 involves either the high affinity hetero-trimeric receptor containing IL-2Rα, IL-2Rβ and the common cytokine receptor gamma chain (originally named IL-2Rγ and now generally denoted as γc) or the intermediate affinity heterodimeric receptor composed of IL-2Rβ and γc. IL-2 stimulation induces the activation of the Janus family tyrosine kinases JAK1 and JAK3, which associate with IL-2Rβ and γc, respectively. These kinases in turn phosphorylate IL-2Rβ and induce tyrosine phosphorylation of STATs (signal transducers and activators of transcription) and various other downstream targets. The downstream signaling pathways activated by IL-2 also involves mitogen-activated protein kinase and phosphoinositide 3-kinase signaling modules, leading to both mitogenic and anti-apoptotic signals. Please access this pathway at [ NetSlim] database. NetPath is a collaborative project between PandeyLab at Johns Hopkins University ( and the Institute of Bioinformatics ( If you use this pathway, please cite the NetPath website until the pathway is published.
last edited


A.Pandey, MaintBot, Khanspers, Mkutmon, MartijnVanIersel, AlexanderPico, NetPath, Christine Chichester, Fehrhart, Egonw, and Eweitz

Cited In


Homo sapiens



Pathway Ontology: Interleukin mediated signaling pathway interleukin-2 signaling pathway


Label Type Compact Identifier
STAT5B Protein ncbigene:6777
STAT3 Protein ncbigene:6774
STAT1 Protein ncbigene:6772
MAPK1 Protein ncbigene:5594
STAT1 Protein ncbigene:6772
AKT1 Protein ncbigene:207
CBL Protein ncbigene:867
GAB2 Protein ncbigene:9846
MAP2K2 Protein ncbigene:5605
SHC1 Protein ncbigene:6464
FYN Protein ncbigene:2534
IL2 Protein ncbigene:3558
CRKL Protein ncbigene:1399
LCK Protein ncbigene:3932
STAT5B Protein ncbigene:6777
IL2RG Protein ncbigene:3561
IL2RA GeneProduct ensembl:ENSG00000134460
RPS6 Protein ncbigene:6194
CCND2 Rna ncbigene:894
MYC Rna ncbigene:4609
FOS Rna ncbigene:2353
JUN Rna ncbigene:3725
BCL2 Rna ncbigene:596
IL2RA Protein ensembl:ENSG00000134460
STAT1 Protein ncbigene:6772
MTOR Protein ncbigene:4137
SOS1 Protein ncbigene:6654
RAF1 Protein ncbigene:5894
MAP2K1 Protein ncbigene:5604
IL2RB Protein ncbigene:3560
STAT3 Protein ncbigene:6774
STAT1 Protein ncbigene:6772
CISH Protein ncbigene:1154
FOXO3A Protein ncbigene:2309
STAT1 Protein ncbigene:6772
GRB2 Protein ncbigene:2885
JAK3 Protein ncbigene:3718
MAPK3 Protein ncbigene:5595
STAT3 Protein ncbigene:6774
PTK2B Protein ncbigene:2185
PTPN11 Protein ncbigene:5781
RPS6KB1 Protein ncbigene:6198
RPS6KB2 Protein ncbigene:6199
JAK1 Protein ncbigene:3716
STAT5A Protein ncbigene:6776
SYK Protein ncbigene:6850
STAT5A Protein ncbigene:6776
STAT5A Protein ncbigene:6776
NMI Protein ncbigene:9111
SOCS3 Protein ncbigene:9021
PIK3R1 Protein ncbigene:5295
STAT3 Protein ncbigene:6774
STAT3 Protein ncbigene:6774
HRAS GeneProduct ensembl:ENSG00000174775


  1. Kandasamy K, Mohan SS, Raju R, Keerthikumar S, Kumar GSS, Venugopal AK, et al. NetPath: a public resource of curated signal transduction pathways. Genome Biol. 2010 Jan 12;11(1):R3. PubMed Europe PMC Scholia