The present invention concerns methods and compositions for forming anti-
cancer vaccine complexes. In preferred embodiments, the anti-
cancer vaccine complex comprises an
antibody moiety that binds to dendritic cells, such as an anti-CD74
antibody or
antigen-binding fragment thereof, attached to an AD (anchoring domain)
moiety and a xenoantigen, such as CD20, attached to a DDD (dimerization and docking domain)
moiety, wherein two copies of the DDD moiety form a
dimer that binds to the AD moiety, resulting in the formation of the vaccine complex. The anti-
cancer vaccine complex is capable of inducing an immune response against xenoantigen expressing cancer cells, such as CD138negCD20+ MM stem cells, and inducing
apoptosis of and inhibiting the growth of or eliminating the cancer cells.