Leukocyte adhesion deficiency I

Gene Information


HUGO name: ITGB2


  • CD18
  • LAD
  • LFA-1
  • MF17
  • cell surface adhesion glycoprotein
  • Integrin, beta 2
  • antigen CD18 (p95)
  • lymphocyte function-associated antigen 1
  • macrophage antigen 1 (mac-1) beta subunit)
  • Integrin beta-2 precursor
  • Cell surface adhesion glycoproteins LFA- 1/CR3/p150,95 beta-subunit
  • Complement receptor C3 beta- subunit


Reference sequences

Chromosomal location


Protein Information


Protein function:

Integrin α-l/β-2 is a receptor for ICAM1, ICAM2, ICAM3 and ICAM4. Integrins α-m/β-2 and α-x/β-2 are receptors for the IC3B fragment of the third complement component and for fibrinogen. Integrin α-x/β 2 recognizes the sequence g-p-r in fibrinogen α-chain. Integrin α-m/β-2 recognizes P1 and P2 peptides of fibrinogen gamma chain. Integrin α-m/β-2 is also a receptor for Factor X. Integrin α-d/β 2 is a receptor for ICAM3 and VCAM1.


Heterodimer of an α and a β subunit. β-2 associates with either α-l, α-m, α-x or α-d.

Subcellular location:

Type I membrane protein

Structures (PDB)


Extracellular domain: 23-700

    Cytoplasmic domain: 724-769

      Vwfa-like domain: 124-363

        4 cysteine-rich tandem repeats domain: 449-617


          Expression pattern for human

          Tissue Expression (%) Clones
          thyroid gland 12.92 2:1136
          whole blood 12.01 4:2445
          nasopharynx 11.36 1:646
          smooth muscle 11.34 1:647
          subchondral bone 5.51 1:1332
          lung with fibrosis 4.96 1:1479
          muscle 4.25 13:22471
          B-cells 3.55 8:16533
          blood 3.48 6:12646
          T cells from T cell leukemia 3.06 1:2397

          Animal models



          C. elegans