This invention discloses monoclonal antibodies (MAbs) which have little or no signaling activity as monomers become potent anti-tumor agents when they are converted into homoconjugates. The homoconjugates exert anti-growth activity by signaling G0/G1 arrest or apoptosis, depending upon which cell surface molecule they bind. This activity is specific and does not require an Fc portion. These conjugates are potent, anti-tumor agents.
