Seroatlas · Human Serome Atlas

IL6

Interleukin-6

Also known as: BSF2, HGF, HSF, IFNB2, IL-6, IL6_HUMAN

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

Protein identityUniProt · HPA

UniProt accession
P05231
Gene
IL6
Ensembl
ENSG00000136244
Chromosome
7
Canonical length
212 aa
Protein class
Cancer-related genes, Candidate cardiovascular disease genes, Disease related genes, FDA approved drug targets, Human disease related genes, Plasma proteins, Predicted intracellular proteins, Predicted membrane proteins, Predicted secreted proteins
Subcellular location
Vesicles
Secretome location
Secreted to blood

OverviewNCBI Gene

This gene encodes a cytokine that functions in inflammation and the maturation of B cells. In addition, the encoded protein has been shown to be an endogenous pyrogen capable of inducing fever in people with autoimmune diseases or infections. The protein is primarily produced at sites of acute and chronic inflammation, where it is secreted into the serum and induces a transcriptional inflammatory response through interleukin 6 receptor, alpha. The functioning of this gene is implicated in a wide variety of inflammation-associated disease states, including suspectibility to diabetes mellitus and systemic juvenile rheumatoid arthritis. Elevated levels of the encoded protein have been found in virus infections, including COVID-19 (disease caused by SARS-CoV-2). [provided by RefSeq, Aug 2020]

Canonical amino-acid sequenceUniProt

212 residues, UniProt reviewed canonical sequence.

>P05231|IL6
     1  MNSFSTSAFG PVAFSLGLLL VLPAAFPAPV PPGEDSKDVA APHRQPLTSS ERIDKQIRYI
    61  LDGISALRKE TCNKSNMCES SKEALAENNL NLPKMAEKDG CFQSGFNEET CLVKIITGLL
   121  EFEVYLEYLQ NRFESSEEQA RAVQMSTKVL IQFLQKKAKN LDAITTPDPT TNASLLTKLQ
   181  AQNQWLQDMT THLILRSFKE FLQSSLRALR QM

LocalizationUniProt · AlphaFold · HPA

Whether an antibody against IL6 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
256 nTPM

Expression across tissuesHPA

Tissue

  • urinary bladder: 256 nTPM
  • adipose tissue: 188 nTPM
  • lung: 141 nTPM
  • heart muscle: 51 nTPM
  • bone marrow: 43 nTPM
  • blood vessel: 42 nTPM

Single-cell type

  • endometrial luminal cells: 716 nCPM
  • vascular smooth muscle cells: 566 nCPM
  • vascular endothelial cells: 222 nCPM
  • pericytes: 203 nCPM
  • fibroblasts: 152 nCPM
  • decidual stromal cells: 92 nCPM

Immune cell

  • naive B-cell: 5.2 nTPM
  • memory B-cell: 4.1 nTPM
  • total PBMC: 0.1 nTPM
  • basophil: 0 nTPM
  • classical monocyte: 0 nTPM
  • eosinophil: 0 nTPM

Brain region

  • choroid plexus: 15 nTPM
  • cerebral cortex: 5.2 nTPM
  • pons: 3.8 nTPM
  • thalamus: 2.9 nTPM
  • white matter: 2.1 nTPM
  • medulla oblongata: 2 nTPM

DiseaseUniProt · ClinVar · IEDB · PubMed

Four sources answering four different questions about IL6.

Disease | AllUniProt

Conditions IL6 is implicated in, by any mechanism.

  • Rheumatoid arthritis systemic juvenile (RASJ) MIM:604302

Disease | AutoantibodyPubMed

Conditions in which antibodies against IL6 are reported. Each links to that disease's full target list.

ReferencesPubMed · IEDB

Publications for IL6 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

105 publications

Show 20 more of 105 total

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)
0.75
gnomAD pLI
0.32
gnomAD missense Z
0
DepMap mean gene effect
0.01
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

InteractionsUniProt · HPA

Protein binding partners of IL6 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 IL6 as an antibody target. Whether an autoantibody or antibody against IL6 could matter depends on whether native IL6 is physically reachable, whether the body needs it intact, and whether it acts in a disease-relevant tissue.

IL6 is annotated as secreted, so native IL6 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.

Source-annotated serology context

The source annotations explicitly mention antibody, autoantibody, autoantigen, or autoimmune context. This is biological context, not study-specific reactivity.

  • In addition, the encoded protein has been shown to be an endogenous pyrogen capable of inducing fever in people with autoimmune diseases or infections.

Canonical record: https://seroatlas.com/gene/IL6. 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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