A novel human monoclonal antibody against cervical cancer: its immunoreactivity with normal tube and ovary and with ovarian tumor tissue.

1-1-2D, a novel human monoclonal antibody (MAb) raised against cervical cancer, was examined for its immunohistochemical reactivity with ovarian cancer. Six of 10 ovarian cancer cell lines showed positive staining, while 3 of 5 cervical cancer cell lines were positive. Among tumor tissues, 15 of 18 (83%) ovarian serous cystadenocarcinomas and 10 of 12 (83%) ovarian clear cell adenocarcinomas were positive. We also performed immunohistochemical staining of the same cancer specimens with OC 125 and compared their reactivity. The frequency of positivity was similar, but the reactivity of the two MAbs was different. 1-1-2D stained the apical surface of the glandular epithelial cells and secretory products of the gland. On the other hand, OC 125 stained the cytoplasm as well as the plasma membrane of the glandular epithelial cells. These results suggest that 1-1-2D MAb recognizes a different antigen from that recognized by OC 125.