Seroatlas · Human Serome Atlas

IL18BP

Interleukin-18-binding protein

Also known as: I18BP_HUMAN, IL18BPa

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

Protein identityUniProt · HPA

UniProt accession
O95998
Gene
IL18BP
Ensembl
ENSG00000137496
Chromosome
11
Canonical length
194 aa
Protein class
Disease related genes, Human disease related genes, Predicted intracellular proteins, Predicted secreted proteins
Subcellular location
Endoplasmic reticulum
Secretome location
Secreted to blood

OverviewNCBI Gene

The protein encoded by this gene functions as an inhibitor of the proinflammatory cytokine, IL18. It binds IL18, prevents the binding of IL18 to its receptor, and thus inhibits IL18-induced IFN-gamma production, resulting in reduced T-helper type 1 immune responses. This protein is constitutively expressed and secreted in mononuclear cells. Elevated level of this protein is detected in the intestinal tissues of patients with Crohn's disease. Alternatively spliced transcript variants encoding different isoforms have been described for this gene. [provided by RefSeq, Feb 2011]

Canonical amino-acid sequenceUniProt

194 residues, UniProt reviewed canonical sequence.

>O95998|IL18BP
     1  MTMRHNWTPD LSPLWVLLLC AHVVTLLVRA TPVSQTTTAA TASVRSTKDP CPSQPPVFPA
    61  AKQCPALEVT WPEVEVPLNG TLSLSCVACS RFPNFSILYW LGNGSFIEHL PGRLWEGSTS
   121  RERGSTGTQL CKALVLEQLT PALHSTNFSC VLVDPEQVVQ RHVVLAQLWA GLRATLPPTQ
   181  EALPSSHSSP QQQG

LocalizationUniProt · AlphaFold · HPA

Whether an antibody against IL18BP 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)
0.43
Highest tissue expression
44 nTPM

Expression across tissuesHPA

Tissue

  • spleen: 44 nTPM
  • lung: 29 nTPM
  • kidney: 23 nTPM
  • lymph node: 19 nTPM
  • appendix: 19 nTPM
  • adrenal gland: 17 nTPM

Single-cell type

  • cardiomyocytes: 63 nCPM
  • epicardial cells: 39 nCPM
  • macrophages: 22 nCPM
  • adipocytes: 20 nCPM
  • kupffer cells: 17 nCPM
  • vascular endothelial cells: 15 nCPM

Immune cell

  • intermediate monocyte: 68 nTPM
  • non-classical monocyte: 57 nTPM
  • eosinophil: 53 nTPM
  • plasmacytoid DC: 49 nTPM
  • gdT-cell: 49 nTPM
  • total PBMC: 36 nTPM

Brain region

  • pons: 14 nTPM
  • thalamus: 14 nTPM
  • medulla oblongata: 13 nTPM
  • hypothalamus: 13 nTPM
  • cerebral cortex: 12 nTPM
  • midbrain: 11 nTPM

DiseaseUniProt · ClinVar · IEDB · PubMed

Four sources answering four different questions about IL18BP.

Disease | AllUniProt

Conditions IL18BP is implicated in, by any mechanism.

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)
1.82
gnomAD pLI
0
gnomAD missense Z
-0.55
DepMap mean gene effect
-0.08
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 IL18BP as an antibody target. Whether an autoantibody or antibody against IL18BP could matter depends on whether native IL18BP is physically reachable, whether the body needs it intact, and whether it acts in a disease-relevant tissue.

IL18BP is annotated as secreted, so native IL18BP 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 IL18BP as an autoantigen. Seroatlas presents hypothesis context only and does not manufacture a known-serology claim.

Canonical record: https://seroatlas.com/gene/IL18BP. 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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