Seroatlas · Human Serome Atlas

CD6

T-cell differentiation antigen CD6

Also known as: CD6_HUMAN, Tp120

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

Protein identityUniProt · HPA

UniProt accession
P30203
Gene
CD6
Ensembl
ENSG00000013725
Chromosome
11
Canonical length
668 aa
Protein class
CD markers, Predicted membrane proteins, Predicted secreted proteins
Secretome location
Secreted to blood

OverviewNCBI Gene

This gene encodes a protein found on the outer membrane of T-lymphocytes as well as some other immune cells. The encoded protein contains three scavenger receptor cysteine-rich (SRCR) domains and a binding site for an activated leukocyte cell adhesion molecule. The gene product is important for continuation of T cell activation. This gene may be associated with susceptibility to multiple sclerosis (PMID: 19525953, 21849685). Multiple transcript variants encoding different isoforms have been found for this gene. [provided by RefSeq, Dec 2011]

Canonical amino-acid sequenceUniProt

668 residues, UniProt reviewed canonical sequence.

>P30203|CD6
     1  MWLFFGITGL LTAALSGHPS PAPPDQLNTS SAESELWEPG ERLPVRLTNG SSSCSGTVEV
    61  RLEASWEPAC GALWDSRAAE AVCRALGCGG AEAASQLAPP TPELPPPPAA GNTSVAANAT
   121  LAGAPALLCS GAEWRLCEVV EHACRSDGRR ARVTCAENRA LRLVDGGGAC AGRVEMLEHG
   181  EWGSVCDDTW DLEDAHVVCR QLGCGWAVQA LPGLHFTPGR GPIHRDQVNC SGAEAYLWDC
   241  PGLPGQHYCG HKEDAGAVCS EHQSWRLTGG ADRCEGQVEV HFRGVWNTVC DSEWYPSEAK
   301  VLCQSLGCGT AVERPKGLPH SLSGRMYYSC NGEELTLSNC SWRFNNSNLC SQSLAARVLC
   361  SASRSLHNLS TPEVPASVQT VTIESSVTVK IENKESRELM LLIPSIVLGI LLLGSLIFIA
   421  FILLRIKGKY ALPVMVNHQH LPTTIPAGSN SYQPVPITIP KEVFMLPIQV QAPPPEDSDS
   481  GSDSDYEHYD FSAQPPVALT TFYNSQRHRV TDEEVQQSRF QMPPLEEGLE ELHASHIPTA
   541  NPGHCITDPP SLGPQYHPRS NSESSTSSGE DYCNSPKSKL PPWNPQVFSS ERSSFLEQPP
   601  NLELAGTQPA FSAGPPADDS SSTSSGEWYQ NFQPPPQPPS EEQFGCPGSP SPQPDSTDND
   661  DYDDISAA

LocalizationUniProt · AlphaFold · HPA

Whether an antibody against CD6 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)
0.49
Highest tissue expression
40 nTPM

Expression across tissuesHPA

Tissue

  • lymph node: 40 nTPM
  • thymus: 37 nTPM
  • tonsil: 27 nTPM
  • appendix: 21 nTPM
  • spleen: 17 nTPM
  • small intestine: 13 nTPM

Single-cell type

  • t-cells: 197 nCPM
  • nk-cells: 27 nCPM
  • megakaryocytes: 19 nCPM
  • pancreatic acinar cells: 16 nCPM
  • thymocytes: 13 nCPM
  • retinal horizontal cells: 12 nCPM

Immune cell

  • memory CD4 T-cell: 52 nTPM
  • memory CD8 T-cell: 48 nTPM
  • naive CD4 T-cell: 35 nTPM
  • gdT-cell: 28 nTPM
  • T-reg: 26 nTPM
  • naive CD8 T-cell: 25 nTPM

Brain region

  • hypothalamus: 5.6 nTPM
  • midbrain: 4.7 nTPM
  • pons: 3.9 nTPM
  • basal ganglia: 3.5 nTPM
  • medulla oblongata: 3.5 nTPM
  • cerebral cortex: 2.6 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)
0.66
gnomAD pLI
0
gnomAD missense Z
1.91
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

InteractionsUniProt · HPA

Protein binding partners of CD6 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 CD6 as an antibody target. Whether an autoantibody or antibody against CD6 could matter depends on whether native CD6 is physically reachable, whether the body needs it intact, and whether it acts in a disease-relevant tissue.

CD6 is annotated at the cell surface, where native CD6 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 CD6 as an autoantigen. Seroatlas presents hypothesis context only and does not manufacture a known-serology claim.

Canonical record: https://seroatlas.com/gene/CD6. 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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