Seroatlas · Human Serome Atlas

IL18RAP

Interleukin-18 receptor accessory protein

Also known as: AcPL, CD218b, I18RA_HUMAN

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

Protein identityUniProt · HPA

UniProt accession
O95256
Gene
IL18RAP
Ensembl
ENSG00000115607
Chromosome
2
Canonical length
599 aa
Protein class
CD markers, Enzymes, Predicted intracellular proteins, Predicted membrane proteins

OverviewNCBI Gene

The protein encoded by this gene is an accessory subunit of the heterodimeric receptor for interleukin 18 (IL18), a proinflammatory cytokine involved in inducing cell-mediated immunity. This protein enhances the IL18-binding activity of the IL18 receptor and plays a role in signaling by IL18. Mutations in this gene are associated with Crohn's disease and inflammatory bowel disease, and susceptibility to celiac disease and leprosy. Alternatively spliced transcript variants of this gene have been described, but their full-length nature is not known. [provided by RefSeq, Feb 2014]

Canonical amino-acid sequenceUniProt

599 residues, UniProt reviewed canonical sequence.

>O95256|IL18RAP
     1  MLCLGWIFLW LVAGERIKGF NISGCSTKKL LWTYSTRSEE EFVLFCDLPE PQKSHFCHRN
    61  RLSPKQVPEH LPFMGSNDLS DVQWYQQPSN GDPLEDIRKS YPHIIQDKCT LHFLTPGVNN
   121  SGSYICRPKM IKSPYDVACC VKMILEVKPQ TNASCEYSAS HKQDLLLGST GSISCPSLSC
   181  QSDAQSPAVT WYKNGKLLSV ERSNRIVVDE VYDYHQGTYV CDYTQSDTVS SWTVRAVVQV
   241  RTIVGDTKLK PDILDPVEDT LEVELGKPLT ISCKARFGFE RVFNPVIKWY IKDSDLEWEV
   301  SVPEAKSIKS TLKDEIIERN IILEKVTQRD LRRKFVCFVQ NSIGNTTQSV QLKEKRGVVL
   361  LYILLGTIGT LVAVLAASAL LYRHWIEIVL LYRTYQSKDQ TLGDKKDFDA FVSYAKWSSF
   421  PSEATSSLSE EHLALSLFPD VLENKYGYSL CLLERDVAPG GVYAEDIVSI IKRSRRGIFI
   481  LSPNYVNGPS IFELQAAVNL ALDDQTLKLI LIKFCYFQEP ESLPHLVKKA LRVLPTVTWR
   541  GLKSVPPNSR FWAKMRYHMP VKNSQGFTWN QLRITSRIFQ WKGLSRTETT GRSSQPKEW

LocalizationUniProt · AlphaFold · HPA

Whether an antibody against IL18RAP 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
Cell surface
Secreted
No
Transmembrane segments
1
Mean surface accessibility (rSASA)
0.37
Highest tissue expression
102 nTPM

Expression across tissuesHPA

Tissue

  • bone marrow: 102 nTPM
  • appendix: 12 nTPM
  • spleen: 11 nTPM
  • adipose tissue: 6.7 nTPM
  • small intestine: 3.5 nTPM
  • lung: 3.2 nTPM

Single-cell type

  • neutrophils: 912 nCPM
  • neutrophil progenitors: 295 nCPM
  • nk-cells: 101 nCPM
  • t-cells: 36 nCPM
  • innate lymphoid cells: 34 nCPM
  • mast cells: 14 nCPM

Immune cell

  • NK-cell: 121 nTPM
  • neutrophil: 70 nTPM
  • MAIT T-cell: 68 nTPM
  • gdT-cell: 48 nTPM
  • eosinophil: 20 nTPM
  • memory CD8 T-cell: 13 nTPM

Brain region

  • cerebral cortex: 2.2 nTPM
  • pons: 1 nTPM
  • choroid plexus: 0.9 nTPM
  • thalamus: 0.9 nTPM
  • spinal cord: 0.7 nTPM
  • medulla oblongata: 0.5 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)
0.58
gnomAD pLI
0
gnomAD missense Z
0.7
DepMap mean gene effect
-0.03
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

InteractionsUniProt · HPA

Protein binding partners of IL18RAP in the human serome: UniProt-annotated complex subunits plus reported interactors. Each links to its own Seroatlas record.

Antibody and autoantibody relevanceSeroatlas analysis

Seroatlas reads IL18RAP as an antibody target. Whether an autoantibody or antibody against IL18RAP could matter depends on whether native IL18RAP is physically reachable, whether the body needs it intact, and whether it acts in a disease-relevant tissue.

IL18RAP is annotated at the cell surface, where native IL18RAP is exposed to circulating antibodies and is a prime autoantibody target that could block, deplete, or overstimulate it.

Annotation status

The present source text does not explicitly label IL18RAP as an autoantigen. Seroatlas presents hypothesis context only and does not manufacture a known-serology claim.

Canonical record: https://seroatlas.com/gene/IL18RAP. 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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