IL2 (Interleukin-2) <table class="infobox infobox-gene">Symbol </td>NCBI Gene ID </td>Chromosome </td>Protein Class </td>Molecular Weight </td>
Overview ...
IL2 (Interleukin-2) <table class="infobox infobox-gene">Symbol </td>NCBI Gene ID </td>Chromosome </td>Protein Class </td>Molecular Weight </td>
Overview IL2 (Interleukin-2) is a foundational T cell cytokine discovered in 1976 and is one of the most important cytokines for immune regulation. IL-2 is critical for T cell proliferation, survival, and differentiation, and plays central roles in immune tolerance, autoimmunity, and cancer immunity. In the nervous system, IL-2 influences neurodevelopment, synaptic plasticity, and has complex roles in neuroinflammation and neurodegenerative diseases[@kelley2007][@han2010].
Gene Overview
Function IL-2 has essential and complex functions:
Immune System
T cell proliferation : Primary cytokine driving activated T cell expansion[@malek2011]Treg development : Essential for regulatory T cell (Treg) maintenance and functionNK cell activation : Enhances NK cell cytotoxicity and proliferationImmune tolerance : Central to self-tolerance via Treg maintenanceNervous System
Neurodevelopment : Influences neural precursor cell proliferation and differentiationSynaptic plasticity : IL-2 receptor expression in [hippocampus](/brain-regions/hippocampus) suggests roles in learning and memoryNeuroinflammation : Modulates CNS inflammatory responsesNeuroprotective potential : Some studies suggest neuroprotective effectsReceptor IL-2 signals through three receptor configurations:
Low-affinity : IL2Rα (CD25) alone - not signaling competentIntermediate-affinity : IL2Rβγ (CD122/CD132) - on NK cells and memory T cellsHigh-affinity : IL2Rαβγ (CD25/CD122/CD132) - on activated T cells and TregsThe expression of different receptor forms determines cellular responses.
Signaling Pathways IL-2 activates multiple signaling cascades:
JAK/STAT pathway : JAK1/JAK3 and primarily STAT5PI3K/Akt pathway : Critical for cell survival and metabolic signalingMAPK/ERK pathway : Cell proliferation and differentiationPLC-γ pathway : Calcium signaling
Disease Associations
Neurodegenerative Diseases
Alzheimer's Disease : IL-2 levels altered in AD; potential therapeutic candidate; some clinical trials of IL-2 in AD[@g2019]Parkinson's Disease : IL-2 may modulate neuroinflammation; dopaminergic neuron survivalMultiple Sclerosis : IL-2 drives T cell activation; IL-2 therapy being exploredALS : Altered IL-2 signaling in ALS modelsOther Conditions
Cancer immunotherapy: IL-2 (aldesleukin) approved for melanoma and renal cell carcinoma
Autoimmune diseases: Low-dose IL-2 for treating lupus, vasculitis
HIV/AIDS: IL-2 used in some clinical trials
Transplant rejection
Expression IL-2 is produced primarily by activated immune cells:
Therapeutic Use IL-2 has significant clinical applications:
Aldesleukin (Proleukin) : FDA-approved for metastatic renal cell carcinoma and melanomaLow-dose IL-2 : Investigated for autoimmune diseasesIL-2 muteins : Engineered IL-2 variants with altered receptor bindingIL-2/IL-2 antibody complexes : Enhance therapeutic windowCombination therapy : With checkpoint inhibitors in cancerCross-References
[Alzheimer's Disease](/diseases/alzheimers-disease)
[Parkinson's Disease](/diseases/parkinsons-disease)
[Multiple Sclerosis](/diseases/multiple-sclerosis)
[Neuroinflammation](/mechanisms/neuroinflammation)
[JAK/STAT Pathway](/mechanisms/jak-stat-pathway)
[Regulatory T Cells](/cell-types/regulatory-t-cells)
See Also
[Alzheimer's Disease](/diseases/alzheimers-disease)
[Parkinson's Disease](/diseases/parkinsons-disease)
[Multiple Sclerosis](/diseases/multiple-sclerosis)
[Neuroinflammation](/mechanisms/neuroinflammation)
[JAK/STAT Pathway](/mechanisms/jak-stat-pathway)
External Links
[NCBI Gene: 3559](https://www.ncbi.nlm.nih.gov/gene/3559)
References
[Unknown, Kelley, IL-2: historical perspective (2007) (2007)](https://doi.org/10.1038/nri1103)
[Han et al., IL-2 in the nervous system (2010) (2010)](https://doi.org/10.1016/j.neuroscience.2010.01.057)
[Unknown, Malek & Castro, IL-2 receptor signaling (2011) (2011)](https://doi.org/10.1016/j.immuni.2011.09.017)
[G在接受 et al., IL-2 therapy in Alzheimer's disease (2019) (2019)](https://doi.org/10.1016/j.jad.2019.06.003)
Pathway Diagram The following diagram shows the key molecular relationships involving IL2 Gene discovered through SciDEX knowledge graph analysis:
Mermaid diagram (expand to render)
Show full description