Vcam1 Protein is an important component in the neurobiology of neurodegenerative diseases. This page provides detailed information about its structure, function, and role in disease processes.
Vascular Cell Adhesion Molecule 1 (VCAM1) is a 739-amino acid type I transmembrane glycoprotein that serves as a critical mediator of leukocyte adhesion and migration across the vascular endothelium. It plays a crucial role in neuroinflammation and blood-brain barrier (BBB) dysfunction in neurodegenerative diseases. VCAM1 is predominantly expressed on activated endothelial cells and is dramatically upregulated by proinflammatory cytokines.
| Attribute |
Value |
| Protein Name |
Vascular Cell Adhesion Molecule 1 |
| Gene Symbol |
VCAM1 |
| Protein Length |
739 amino acids |
| Molecular Weight |
~81 kDa (unglycosylated); 100-110 kDa (glycosylated) |
| UniProt ID |
P19320 |
| PDB Structures |
1ASJ, 1BCZ, 1DC4, 1KV2 |
| Cellular Location |
Plasma membrane (type I transmembrane) |
| Protein Family |
Immunoglobulin superfamily (IgSF) |
¶ Domain Structure
VCAM1 contains distinct structural domains:
¶ Extracellular Domain (20-698 aa)
- Ig-like domain D1 (20-109 aa): N-terminal domain containing the primary integrin binding site
- Ig-like domain D2 (110-201 aa): Contributes to ligand binding
- Ig-like domain D3 (202-292 aa): Provides structural framework
- Ig-like domain D4 (293-387 aa): Flexible linker region
- Ig-like domain D5 (388-480 aa): D4-D5 linker
- Ig-like domain D6 (481-576 aa): Supports domain organization
- Ig-like domain D7 (577-698 aa): C-terminal extracellular domain
¶ Transmembrane Domain (699-723 aa)
- Single α-helical membrane-spanning segment
- Contains a cysteine residue important for dimerization
- Short cytoplasmic domain
- Contains motifs for protein trafficking and localization
VCAM1 binds primarily to the integrin α4β1 (VLA-4) and α4β7:
| Integrin |
Alternative Name |
Dissociation Constant (Kd) |
Expression |
| ITGA4/ITGB1 |
VLA-4 |
~30 nM |
Lymphocytes, monocytes, eosinophils |
| ITGA4/ITGB7 |
α4β7 |
~100 nM |
Gut-homing lymphocytes |
The D1 Ig-like domain contains the primary binding site for VLA-4, involving metal ion-dependent adhesion sites (MIDAS).
- Leukocyte adhesion: Mediates firm adhesion of circulating leukocytes to activated endothelium
- Transendothelial migration: Facilitates diapedesis across the blood-brain barrier
- Cell survival: VCAM1-VLA-4 interaction provides pro-survival signals through PI3K/Akt pathway
- Angiogenesis: Supports new blood vessel formation in inflammation
VCAM1 is extensively N-glycosylated at multiple asparagine residues:
- N-glycosylation is essential for proper protein folding
- Critical for ligand binding affinity
- Affects receptor interactions
- Shedding: Metalloproteinases can cleave the extracellular domain
- Soluble VCAM1 (sVCAM1): Released form used as inflammatory biomarker
Key structural studies reveal:
- 1ASJ: VCAM1 D1-D4 domains
- 1BCZ: VCAM1 D1 with VLA-4
- 1DC4: VCAM1 D1-D7 complete ectodomain
- 1KV2: VCAM1-VLA-4 complex
¶ Domain Organization
The seven Ig-like domains are arranged in a linear fashion with flexible interdomain linkers, allowing simultaneous engagement of multiple ligands and receptors.
VCAM1 contributes significantly to AD pathogenesis:
- BBB dysfunction: Elevated expression on brain endothelial cells disrupts the blood-brain barrier
- Immune cell infiltration: Mediates peripheral immune cell trafficking into the brain
- Cerebral amyloid angiopathy (CAA): Associated with vascular amyloid deposits
- Neurovascular coupling: Dysregulation affects cerebral blood flow regulation
- Pericyte function: Affects pericyte coverage and BBB integrity
In PD, VCAM1 mediates neuroinflammation:
- Substantia nigra: Increased expression in dopaminergic regions
- Microglial activation: Facilitates recruitment of peripheral macrophages
- BBB permeability: Contributes to blood-brain barrier breakdown
- Disease progression: Levels correlate with Hoehn and Yahr stage
VCAM1 is central to MS pathogenesis:
- Leukocyte trafficking: Essential for T cell migration across the BBB
- Lesion formation: High expression in active demyelinating lesions
- Clinical therapy: Natalizumab blocks VLA-4, preventing VCAM1-mediated adhesion
¶ Stroke and Ischemic Injury
VCAM1 mediates post-ischemic inflammation:
- Early upregulation: Rapidly induced after cerebral ischemia
- Reperfusion injury: Mediates secondary inflammatory damage
- Therapeutic potential: Blocking VCAM1 reduces infarct size in animal models
- Angiogenesis: Involved in post-stroke blood vessel repair
VCAM1 is elevated in ALS:
- Motor cortex: Increased expression in motor cortex blood vessels
- Spinal cord: Mediates inflammatory cell infiltration
- Disease progression: Correlates with rate of functional decline
¶ Expression and Regulation
- Endothelial cells: High expression at cell junctions, especially after activation
- Smooth muscle cells: Inducible in pathological states
- Astrocytes: Induced in reactive astrocytes
- Macrophages/monocytes: Express VCAM1 in inflamed tissues
- Epithelial cells: Variable, inducible expression
- NF-κB: Primary transcriptional regulator
- AP-1: Cooperates with NF-κB for maximal induction
- Cytokines: TNF-α, IL-1β, IFN-γ strongly induce expression
- Shear stress: Mechanical forces modulate expression
- Oxidized lipids: Increase expression in atherosclerosis
| Strategy |
Agent |
Development Status |
Clinical Context |
| VLA-4 Antagonists |
Natalizumab |
Approved (MS) |
Blocks α4 integrin; prevents VCAM1 binding |
| VLA-4 Antagonists |
Firategrast |
Clinical trials |
Oral small molecule antagonist |
| VLA-4 Antagonists |
Vedolizumab |
Approved (IBD) |
Gut-specific; not for CNS diseases |
| Blocking Antibodies |
Anti-VCAM1 antibodies |
Preclinical |
Shown to reduce immune cell infiltration |
| Small Molecules |
VCAM1-VLA-4 inhibitors |
Discovery phase |
High-throughput screening |
| Gene Therapy |
siRNA targeting VCAM1 |
Preclinical |
AAV-delivered silencing |
¶ Diagnostic and Prognostic Value
- Soluble VCAM1 (sVCAM1): Elevated in AD, PD, MS, stroke
- Blood/CSF correlation: Indicates CNS vs peripheral inflammation
- Disease staging: Higher levels correlate with advanced disease
- Treatment monitoring: Changes reflect therapeutic response
- VCAM1 imaging: PET ligands for visualizing neuroinflammation
- Single-cell analysis: VCAM1 expression in distinct immune populations
- Organoid models: BBB models incorporating VCAM1 for drug testing
The study of Vcam1 Protein has evolved significantly over the past decades. Research in this area has revealed important insights into the underlying mechanisms of neurodegeneration and continues to drive therapeutic development.
Historical context and key discoveries in this field have shaped our current understanding and will continue to guide future research directions.