CD117 is a transmembrane, tyrosine kinase growth factor receptor also known as c-Kit and mast/stem cell factor receptor (SCFR). It binds the c-Kit ligand (also known as steel factor, stem cell factor, and mast cell growth factor). CD117 is expressed on hematopoietic stem cells (including multipotent hematopoietic stem cells, progenitors committed to myeloid and/or erythroid lineages, and T and B cell precursors), mast cells, and acute myeloid leukemia cells. CD117 plays an essential role in the regulation of cell survival and proliferation, hematopoiesis, stem cell maintenance, gametogenesis, mast cell development, migration and function, and in melanogenesis.
Anti-CD117-SAP is a bonded toxin between a biotinylated rat monoclonal CD117 antibody and the secondary conjugate Streptavidin-ZAP containing the ribosome-inactivating protein, saporin. Anti-CD117-SAP specifically eliminates cells that express CD117 in mice.