CD44 Antibody

Background

CD44 was designed, produced, and validated as part of the Joy Cappel Young Investigator Award (JCYIA). CD44 is a receptor for hyaluronic acid (HA), an integral component of the extracellular matrix. CD44 mediates cell-cell and cell-matrix interactions through its affinity for HA, and can also interact with ligands such as osteopontin, collagens, and matrix metalloproteinases (MMPs). The multiple protein isoforms are encoded by a single gene by alternative splicing and are further modified by a range of post-translational modifications. CD44 function is controlled by these posttranslational modifications. The major physiological role of CD44 is to maintain organ and tissue structure via cell-cell and cell-matrix adhesion, but certain variant isoforms can also mediate lymphocyte activation and homing, and the presentation of chemical factors and hormones. CD44 participates in a wide variety of cellular functions including lymphocyte activation, recirculation and homing, hematopoiesis, and tumor metastasis. CD44 is a multi-structural and multi-functional cell surface molecule involved in cell proliferation, cell differentiation, cell migration, angiogenesis, presentation of cytokines, chemokines, and growth factors to the corresponding receptors, and docking of proteases at the cell membrane, as well as in signaling for cell survival. All these biological properties are essential to the physiological activities of normal cells, but they are also associated with the pathologic activities of cancer cells. CD44, particularly its variants, may be useful as a diagnostic or prognostic marker of malignancy and, in at least some human cancers, it may be a potential target for cancer therapy.