CD166. also known as Activated Leukocyte Cell Adhesion Molecule (ALCAM), is a transmembrane glycoprotein belonging to the immunoglobulin superfamily. It plays critical roles in cell-cell adhesion, immune response modulation, and cellular signaling. Structurally, CD166 contains five extracellular immunoglobulin-like domains, a transmembrane region, and a cytoplasmic tail. It mediates both homophilic (CD166-CD166) and heterophilic (CD166-CD6) interactions, facilitating processes like T-cell activation, neuronal development, and cancer cell migration.
CD166 antibodies are essential tools for studying its expression and function. In research, these antibodies are used in techniques such as flow cytometry, immunohistochemistry, and Western blotting to detect CD166 in tissues or cells. Elevated CD166 expression is linked to various cancers, including breast, colon, and melanoma, where it often correlates with tumor progression, metastasis, and cancer stem cell activity. Conversely, in some contexts, CD166 may act as a tumor suppressor, highlighting its context-dependent roles.
Clinically, CD166 antibodies hold diagnostic and therapeutic potential. They serve as biomarkers for cancer prognosis and are explored in targeted therapies, such as antibody-drug conjugates or immune checkpoint modulation. Additionally, CD166's involvement in autoimmune diseases and transplant rejection has spurred interest in blocking its interactions with CD6 to regulate immune responses. Both monoclonal and polyclonal CD166 antibodies are commercially available, with specificity and applications varying by clone and epitope recognition. Ongoing research aims to clarify its dual roles and optimize therapeutic strategies leveraging CD166 targeting.