Multiple epitopes of the human ovarian cancer antigen 14C1 recognised by human IgG antibodies: their potential in immunotherapy.

We have defined a novel ovarian cancer-associated membrane antigen, 14C1, using human monoclonal antibodies derived by EBV-transformation of in situ sensitised patients' B-cells. The pattern of recognition of this antigen by these antibodies suggests that at least three epitopes are discernable. These antibodies can be used to promote the in vitro killing of ovarian cancer cells by activated macrophages and cytokines, implying a role for this antigen in the immunotherapy of ovarian malignancies. Evidence is presented that the 14C1 antigen may have some transmembrane signalling function.