Seroatlas · Human Serome Atlas

ICAM3

Intercellular adhesion molecule 3

Also known as: CD50, CDW50, ICAM-R, ICAM3_HUMAN

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

Protein identityUniProt · HPA

UniProt accession
P32942
Gene
ICAM3
Ensembl
ENSG00000076662
Chromosome
19
Canonical length
547 aa
Protein class
CD markers, Plasma proteins, Predicted membrane proteins
Subcellular location
Nucleoplasm,Nuclear membrane,Mitochondria

OverviewNCBI Gene

The protein encoded by this gene is a member of the intercellular adhesion molecule (ICAM) family. All ICAM proteins are type I transmembrane glycoproteins, contain 2-9 immunoglobulin-like C2-type domains, and bind to the leukocyte adhesion LFA-1 protein. This protein is constitutively and abundantly expressed by all leucocytes and may be the most important ligand for LFA-1 in the initiation of the immune response. It functions not only as an adhesion molecule, but also as a potent signalling molecule. Alternative splicing results in multiple transcript variants encoding different isoforms. [provided by RefSeq, Feb 2016]

Canonical amino-acid sequenceUniProt

547 residues, UniProt reviewed canonical sequence.

>P32942|ICAM3
     1  MATMVPSVLW PRACWTLLVC CLLTPGVQGQ EFLLRVEPQN PVLSAGGSLF VNCSTDCPSS
    61  EKIALETSLS KELVASGMGW AAFNLSNVTG NSRILCSVYC NGSQITGSSN ITVYRLPERV
   121  ELAPLPPWQP VGQNFTLRCQ VEDGSPRTSL TVVLLRWEEE LSRQPAVEEP AEVTATVLAS
   181  RDDHGAPFSC RTELDMQPQG LGLFVNTSAP RQLRTFVLPV TPPRLVAPRF LEVETSWPVD
   241  CTLDGLFPAS EAQVYLALGD QMLNATVMNH GDTLTATATA TARADQEGAR EIVCNVTLGG
   301  ERREARENLT VFSFLGPIVN LSEPTAHEGS TVTVSCMAGA RVQVTLDGVP AAAPGQPAQL
   361  QLNATESDDG RSFFCSATLE VDGEFLHRNS SVQLRVLYGP KIDRATCPQH LKWKDKTRHV
   421  LQCQARGNPY PELRCLKEGS SREVPVGIPF FVNVTHNGTY QCQASSSRGK YTLVVVMDIE
   481  AGSSHFVPVF VAVLLTLGVV TIVLALMYVF REHQRSGSYH VREESTYLPL TSMQPTEAMG
   541  EEPSRAE

LocalizationUniProt · AlphaFold · HPA

Whether an antibody against ICAM3 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)
0.35
Highest tissue expression
167 nTPM

Expression across tissuesHPA

Tissue

  • bone marrow: 167 nTPM
  • spleen: 89 nTPM
  • lymph node: 73 nTPM
  • appendix: 48 nTPM
  • thymus: 44 nTPM
  • tonsil: 42 nTPM

Single-cell type

  • neutrophils: 596 nCPM
  • neutrophil progenitors: 223 nCPM
  • plasma cells: 212 nCPM
  • hepatocytes: 198 nCPM
  • nk-cells: 123 nCPM
  • t-cells: 120 nCPM

Immune cell

  • neutrophil: 1,773 nTPM
  • eosinophil: 807 nTPM
  • total PBMC: 583 nTPM
  • MAIT T-cell: 414 nTPM
  • T-reg: 402 nTPM
  • non-classical monocyte: 391 nTPM

Brain region

  • cerebral cortex: 6.7 nTPM
  • thalamus: 5.9 nTPM
  • spinal cord: 5.3 nTPM
  • medulla oblongata: 4.2 nTPM
  • midbrain: 4 nTPM
  • hypothalamus: 3.8 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)
1.92
gnomAD pLI
0
gnomAD missense Z
0.3
DepMap mean gene effect
-0.06
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 ICAM3 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 ICAM3 as an antibody target. Whether an autoantibody or antibody against ICAM3 could matter depends on whether native ICAM3 is physically reachable, whether the body needs it intact, and whether it acts in a disease-relevant tissue.

ICAM3 is annotated at the cell surface, where native ICAM3 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 ICAM3 as an autoantigen. Seroatlas presents hypothesis context only and does not manufacture a known-serology claim.

Canonical record: https://seroatlas.com/gene/ICAM3. 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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