Seroatlas · Human Serome Atlas

IL15

Interleukin-15

Also known as: IL-15, IL15_HUMAN, MGC9721

Cross-references: UniProt · Ensembl · Human Protein Atlas · GeneCards · NCBI Gene

Protein identityUniProt · HPA

UniProt accession
P40933
Gene
IL15
Ensembl
ENSG00000164136
Chromosome
4
Canonical length
162 aa
Protein class
Cancer-related genes, Predicted intracellular proteins, Predicted secreted proteins
Subcellular location
Nucleoplasm,Nuclear speckles
Secretome location
Secreted to blood

OverviewNCBI Gene

The protein encoded by this gene is a cytokine that regulates T and natural killer cell activation and proliferation. This cytokine and interleukine 2 share many biological activities. They are found to bind common hematopoietin receptor subunits, and may compete for the same receptor, and thus negatively regulate each other's activity. The number of CD8+ memory cells is shown to be controlled by a balance between this cytokine and IL2. This cytokine induces the activation of JAK kinases, as well as the phosphorylation and activation of transcription activators STAT3, STAT5, and STAT6. Studies of the mouse counterpart suggested that this cytokine may increase the expression of apoptosis inhibitor BCL2L1/BCL-x(L), possibly through the transcription activation activity of STAT6, and thus prevent apoptosis. Alternatively spliced transcript variants of this gene have been reported. [provided by RefSeq, Feb 2011]

Canonical amino-acid sequenceUniProt

162 residues, UniProt reviewed canonical sequence.

>P40933|IL15
     1  MRISKPHLRS ISIQCYLCLL LNSHFLTEAG IHVFILGCFS AGLPKTEANW VNVISDLKKI
    61  EDLIQSMHID ATLYTESDVH PSCKVTAMKC FLLELQVISL ESGDASIHDT VENLIILANN
   121  SLSSNGNVTE SGCKECEELE EKNIKEFLQS FVHIVQMFIN TS

LocalizationUniProt · AlphaFold · HPA

Whether an antibody against IL15 can act on the native protein depends on physical access: surface and secreted proteins are reachable by circulating antibodies, intracellular proteins usually are not.

Antibody reachability
Secreted
Secreted
Yes
Transmembrane segments
0
Mean surface accessibility (rSASA)
0.37
Highest tissue expression
13 nTPM

Expression across tissuesHPA

Tissue

  • thyroid gland: 13 nTPM
  • spleen: 13 nTPM
  • lymph node: 9.1 nTPM
  • small intestine: 8.4 nTPM
  • skeletal muscle: 8.1 nTPM
  • blood vessel: 7.7 nTPM

Single-cell type

  • decidual stromal cells: 567 nCPM
  • endometrial stromal cells: 381 nCPM
  • cdc: 150 nCPM
  • epicardial cells: 148 nCPM
  • monocytes: 85 nCPM
  • kupffer cells: 81 nCPM

Immune cell

  • non-classical monocyte: 17 nTPM
  • classical monocyte: 16 nTPM
  • intermediate monocyte: 15 nTPM
  • basophil: 10 nTPM
  • total PBMC: 6.1 nTPM
  • myeloid DC: 5.5 nTPM

Brain region

  • medulla oblongata: 6.3 nTPM
  • cerebellum: 5.8 nTPM
  • cerebral cortex: 5.7 nTPM
  • white matter: 5.5 nTPM
  • pons: 5.3 nTPM
  • thalamus: 5.1 nTPM

ReferencesPubMed · IEDB

Publications for IL15 from three distinct lines of evidence, kept separate because they answer different questions: whether antibodies are directed at the protein, whether a B-cell epitope has been mapped on it, and whether a T-cell epitope has. Each is labelled with its source.

Reference: AutoantibodyPubMed

2 publications

Sources: PubMed — antigen-level antibody evidence from a custom retrieval. Records matching a controlled set of autoantibody terms (the MeSH descriptors Autoantibodies and Autoantigens, with title and abstract term variants) were obtained through NCBI E-utilities, and their titles and abstracts parsed for constructions that direct an antibody at a named protein rather than for co-occurrence. Captured names were resolved against UniProt nomenclature and each antigen adjudicated individually against the source text. Bibliographic records from PubMed and MeSH, U.S. National Library of Medicine; citation metrics from NIH iCite (Hutchins et al., PLoS Biology 2016). Titles link to PubMed; abstracts are not reproduced here. The NLM does not endorse this analysis.

Genetic constraint and essentialitygnomAD · DepMap

Does the body need this protein intact? Low LOEUF or a strong DepMap dependency means loss or blockade of the protein is likely to be felt.

gnomAD LOEUF (loss-of-function intolerance)
0.57
gnomAD pLI
0.71
gnomAD missense Z
0.07
DepMap mean gene effect
0.07
DepMap dependency class
none

Cancer expressionTCGA

Across TCGA tumor cohorts, this protein is over-expressed in roughly 4% of surveyed tumor types (aggregate summary; per-cohort expression, alteration, and survival load in the interactive view).

OntologyGO

Biological processes

Molecular functions

Cellular components

Protein domainsUniProt · Pfam · InterPro

KeywordsUniProt

Antibody and autoantibody relevanceSeroatlas analysis

Seroatlas reads IL15 as an antibody target. Whether an autoantibody or antibody against IL15 could matter depends on whether native IL15 is physically reachable, whether the body needs it intact, and whether it acts in a disease-relevant tissue.

IL15 is annotated as secreted, so native IL15 circulates and is directly accessible to antibodies. Secreted and cell-surface proteins are the autoantibody targets most likely to act like drugs, blocking or depleting the native protein.

Annotation status

The present source text does not explicitly label IL15 as an autoantigen. Seroatlas presents hypothesis context only and does not manufacture a known-serology claim.

Canonical record: https://seroatlas.com/gene/IL15. Study-independent annotations aggregated from UniProt, Human Protein Atlas, PubMed, IEDB, Pfam, InterPro, Gene Ontology, AlphaFold, gnomAD, DepMap, ClinVar, TCGA. Catalog release seroatlas-reviewed-human-uniprot-20260313.

Seroatlas is the reference for exploring autoantibody and antibody serology at the human-protein level: the autoreactome and human serome, multiplex serology (HuProt, HuScan, VirScan, PhIP-Seq).

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