Disclosed are immunoconjugates having specificity for CD138 that diminish adhesion of CD138 expressing tumor cells to stroma cells and methods of using the same. This deminished adhesion renders the tumor cells not only susceptible to the immunconjugate, but also to other agents, in particular cytotoxic agents.在此揭露的是對CD138具專一性之免疫綴合物,其會減少表現CD138之腫瘤細胞附著於基質細胞,以及使用該免疫綴合物之方法。此附著力之減少,使得該腫瘤細胞不僅易受該免疫綴合物之影響,且易受其它藥劑之影響,特別是細胞毒性劑。