Seroatlas · Human Serome Atlas

ALCAM

CD166 antigen

Also known as: CD166, CD166_HUMAN, MEMD

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

Protein identityUniProt · HPA

UniProt accession
Q13740
Gene
ALCAM
Ensembl
ENSG00000170017
Chromosome
3
Canonical length
583 aa
Protein class
Cancer-related genes, CD markers, Plasma proteins, Predicted membrane proteins, Predicted secreted proteins, Transporters
Subcellular location
Vesicles
Secretome location
Secreted to blood
Quaternary structure
Homodimer

OverviewNCBI Gene

This gene encodes activated leukocyte cell adhesion molecule (ALCAM), also known as CD166 (cluster of differentiation 166), which is a member of a subfamily of immunoglobulin receptors with five immunoglobulin-like domains (VVC2C2C2) in the extracellular domain. This protein binds to T-cell differentiation antigene CD6, and is implicated in the processes of cell adhesion and migration. Multiple alternatively spliced transcript variants encoding different isoforms have been found. [provided by RefSeq, Aug 2011]

Canonical amino-acid sequenceUniProt

583 residues, UniProt reviewed canonical sequence.

>Q13740|ALCAM
     1  MESKGASSCR LLFCLLISAT VFRPGLGWYT VNSAYGDTII IPCRLDVPQN LMFGKWKYEK
    61  PDGSPVFIAF RSSTKKSVQY DDVPEYKDRL NLSENYTLSI SNARISDEKR FVCMLVTEDN
   121  VFEAPTIVKV FKQPSKPEIV SKALFLETEQ LKKLGDCISE DSYPDGNITW YRNGKVLHPL
   181  EGAVVIIFKK EMDPVTQLYT MTSTLEYKTT KADIQMPFTC SVTYYGPSGQ KTIHSEQAVF
   241  DIYYPTEQVT IQVLPPKNAI KEGDNITLKC LGNGNPPPEE FLFYLPGQPE GIRSSNTYTL
   301  TDVRRNATGD YKCSLIDKKS MIASTAITVH YLDLSLNPSG EVTRQIGDAL PVSCTISASR
   361  NATVVWMKDN IRLRSSPSFS SLHYQDAGNY VCETALQEVE GLKKRESLTL IVEGKPQIKM
   421  TKKTDPSGLS KTIICHVEGF PKPAIQWTIT GSGSVINQTE ESPYINGRYY SKIIISPEEN
   481  VTLTCTAENQ LERTVNSLNV SAISIPEHDE ADEISDENRE KVNDQAKLIV GIVVGLLLAA
   541  LVAGVVYWLY MKKSKTASKH VNKDLGNMEE NKKLEENNHK TEA

LocalizationUniProt · AlphaFold · HPA

Whether an antibody against ALCAM 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)
0.36
Highest tissue expression
413 nTPM

Expression across tissuesHPA

Tissue

  • parathyroid gland: 413 nTPM
  • blood vessel: 86 nTPM
  • breast: 76 nTPM
  • lung: 70 nTPM
  • thyroid gland: 58 nTPM
  • spinal cord: 56 nTPM

Single-cell type

  • respiratory secretory cells: 1,808 nCPM
  • endometrial glandular cells: 1,693 nCPM
  • endometrial luminal cells: 1,651 nCPM
  • respiratory deuterosomal cells: 1,650 nCPM
  • conjunctival goblet cells: 1,485 nCPM
  • transitional alveolar cells: 1,377 nCPM

Immune cell

  • myeloid DC: 30 nTPM
  • plasmacytoid DC: 11 nTPM
  • neutrophil: 5.3 nTPM
  • memory B-cell: 4.8 nTPM
  • classical monocyte: 4.7 nTPM
  • eosinophil: 3.5 nTPM

Brain region

  • white matter: 161 nTPM
  • hypothalamus: 137 nTPM
  • midbrain: 105 nTPM
  • pons: 97 nTPM
  • medulla oblongata: 96 nTPM
  • basal ganglia: 87 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)
0.39
gnomAD pLI
0.73
gnomAD missense Z
0.99
DepMap mean gene effect
-0.1
DepMap dependency class
selective

Cancer expressionTCGA

Across TCGA tumor cohorts, this protein is over-expressed in roughly 6% 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 ALCAM 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 ALCAM as an antibody target. Whether an autoantibody or antibody against ALCAM could matter depends on whether native ALCAM is physically reachable, whether the body needs it intact, and whether it acts in a disease-relevant tissue.

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

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