Seroatlas · Human Serome Atlas

IL27

Interleukin-27 subunit alpha

Also known as: IL-27, IL-27A, IL27A, IL27A_HUMAN, IL27p28, IL30, MGC71873, p28

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

Protein identityUniProt · HPA

UniProt accession
Q8NEV9
Gene
IL27
Ensembl
ENSG00000197272
Chromosome
16
Canonical length
243 aa
Protein class
Predicted intracellular proteins, Predicted secreted proteins
Secretome location
Secreted to blood

OverviewNCBI Gene

The protein encoded by this gene is one of the subunits of a heterodimeric cytokine complex. This protein is related to interleukin 12A (IL12A). It interacts with Epstein-Barr virus induced gene 3 (EBI3), a protein similar to interleukin 12B (IL12B), and forms a complex that has been shown to drive rapid expansion of naive but not memory CD4(+) T cells. The complex is also found to synergize strongly with interleukin 12 to trigger interferon gamma (IFNG) production of naive CD4(+) T cells. The biological effects of this cytokine are mediated by the class I cytokine receptor (WSX1/TCRR). [provided by RefSeq, Jul 2008]

Canonical amino-acid sequenceUniProt

243 residues, UniProt reviewed canonical sequence.

>Q8NEV9|IL27
     1  MGQTAGDLGW RLSLLLLPLL LVQAGVWGFP RPPGRPQLSL QELRREFTVS LHLARKLLSE
    61  VRGQAHRFAE SHLPGVNLYL LPLGEQLPDV SLTFQAWRRL SDPERLCFIS TTLQPFHALL
   121  GGLGTQGRWT NMERMQLWAM RLDLRDLQRH LRFQVLAAGF NLPEEEEEEE EEEEEERKGL
   181  LPGALGSALQ GPAQVSWPQL LSTYRLLHSL ELVLSRAVRE LLLLSKAGHS VWPLGFPTLS
   241  PQP

LocalizationUniProt · AlphaFold · HPA

Whether an antibody against IL27 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)
0.38
Highest tissue expression
26 nTPM

Expression across tissuesHPA

Tissue

  • liver: 26 nTPM
  • spleen: 1.6 nTPM
  • appendix: 1.1 nTPM
  • bone marrow: 0.8 nTPM
  • placenta: 0.6 nTPM
  • testis: 0.6 nTPM

Single-cell type

  • syncytiotrophoblasts: 34 nCPM
  • hepatocytes: 25 nCPM
  • neutrophils: 12 nCPM
  • migrating cytotrophoblasts: 5 nCPM
  • breast lactating cells: 3.8 nCPM
  • extravillous trophoblasts: 3.6 nCPM

Immune cell

  • intermediate monocyte: 3.8 nTPM
  • classical monocyte: 3.6 nTPM
  • neutrophil: 2.1 nTPM
  • NK-cell: 1.5 nTPM
  • total PBMC: 1 nTPM
  • eosinophil: 0.8 nTPM

Brain region

  • thalamus: 1.7 nTPM
  • medulla oblongata: 1.3 nTPM
  • cerebral cortex: 1.2 nTPM
  • midbrain: 1.1 nTPM
  • cerebellum: 1 nTPM
  • hippocampal formation: 1 nTPM

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)
0.51
gnomAD pLI
0.78
gnomAD missense Z
1.08
DepMap mean gene effect
-0.04
DepMap dependency class
selective

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 IL27 as an antibody target. Whether an autoantibody or antibody against IL27 could matter depends on whether native IL27 is physically reachable, whether the body needs it intact, and whether it acts in a disease-relevant tissue.

IL27 is annotated as secreted, so native IL27 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 IL27 as an autoantigen. Seroatlas presents hypothesis context only and does not manufacture a known-serology claim.

Canonical record: https://seroatlas.com/gene/IL27. 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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