This product is comprised of an anti-CD33 monoclonal antibody (Lintuzumab) labeled with iFluor 647. iFluor 647 is a far-red-fluorescent dye and it's excitation/emission is 650/665 nm.
CD33 or Siglec-3 is a transmembrane receptor expressed on cells of myeloid lineage. It is usually considered myeloid-specific, but it can also be found on some lymphoid cells. It binds sialic acids, therefore is a member of the SIGLEC family of lectins.