ICAM-1 Human

ICAM-1 was discovered in the 1980s and identified as a ligand for the β2 integrin lymphocyte function-associated antigen (LFA)-1 (CD11a/CD18) . Structurally, ICAM-1 is characterized by heavy glycosylation and consists of an amino-terminus extracellular domain, a single transmembrane domain, and a carboxy-terminus cytoplasmic domain . The extracellular domain is composed of multiple loops created by disulfide bridges, and the dominant secondary structure is the beta sheet .

ICAM-1 is typically expressed on endothelial cells and cells of the immune system, such as leukocytes . Its expression can be induced by cytokines like interleukin-1 (IL-1) and tumor necrosis factor (TNF) . Upon cytokine stimulation, the concentration of ICAM-1 on cell membranes increases significantly .

ICAM-1 is essential for stabilizing cell-cell interactions and facilitating leukocyte endothelial transmigration . It acts as a ligand for LFA-1, a receptor found on leukocytes, enabling them to bind to endothelial cells and transmigrate into tissues . This process is crucial for the immune response, particularly in inflammation and immune surveillance .

ICAM-1 plays a central role in various inflammatory diseases, including ulcerative colitis and rheumatoid arthritis . It is also implicated in neuroinflammatory conditions such as Parkinson’s disease, where it influences ferroptosis, an iron-dependent form of cell death . The interaction between ICAM-1, glial cells, and T cells is a subject of ongoing research, with potential implications for novel therapeutic interventions .

Human recombinant ICAM-1 is produced using recombinant DNA technology, which involves inserting the ICAM1 gene into a suitable expression system, such as bacteria or mammalian cells. This allows for the large-scale production of ICAM-1 for research and therapeutic purposes. Recombinant ICAM-1 is used in various studies to understand its role in immune responses and to develop potential treatments for inflammatory and neurodegenerative diseases.