Irie R F, Giuliano A E, Morton D L
J Natl Cancer Inst. 1979 Aug;63(2):367-73.
Oncofetal antigen (OFA) has been defined with the use of human natural antibodies as a membrane antigen of human cancer cells that cross-reacts with human fetal brain tissues. The immunogen that elicits the antibody is unknown. The present study was undertaken to examine the immunogenicity of the OFA found on tumor cells. Postoperative melanoma patients were immunized with OFA-positive melanoma cells. Anti-OFA reactivities in the immunized sera were titrated by the immune adherence assay with the use of a known OFA-positive cultured melanoma cell line, M14, as target cell. Alloantibodies were excluded by absorption with lymphoblastoid cells autologous to M14. Anti-OFA antibody then was identified by absorption with fetal brain. In 6 months of immunization, 19 of 23 patients produced increased anti-OFA antibodies. The peak titers ranged from 1:16 to 1:2,048. Sera from 18 patients who were not immunized also were tested for 6 months postoperatively, and none had significant increases in antibody titers. The increase of anti-OFA antibody titer in response to the immunization with OFA-positive tumor cells suggests the immunogenic capability of tumor-related OFA in man.
癌胚抗原（OFA）已被定义为一种人类癌细胞的膜抗原，它可与人类胎儿脑组织发生交叉反应，其检测使用的是人类天然抗体。引发该抗体的免疫原尚不清楚。本研究旨在检测肿瘤细胞上发现的OFA的免疫原性。对黑色素瘤术后患者用OFA阳性的黑色素瘤细胞进行免疫。使用已知的OFA阳性培养黑色素瘤细胞系M14作为靶细胞，通过免疫黏附试验滴定免疫血清中的抗OFA反应性。通过用与M14自体的淋巴母细胞进行吸收来排除同种抗体。然后通过用胎儿脑进行吸收来鉴定抗OFA抗体。在免疫的6个月内，23例患者中有19例产生了升高的抗OFA抗体。峰值滴度范围为1:16至1:2048。对18例未免疫患者的血清也在术后6个月进行了检测，无一例抗体滴度有显著升高。抗OFA抗体滴度因用OFA阳性肿瘤细胞免疫而升高，这表明肿瘤相关OFA在人体内具有免疫原性。
