Usefulness of radioimmunodetection and radioimmunotherapy with polymonoclonal antitumor antibody using melanoma bearing mice.

本研究旨在用两种不同的抗黑色素瘤抗体在体内验证不同的生物分布。虽然放射性同位素标记的单抗闪烁成像对肿瘤的成像被证明是有用的，但由于单抗仅结合肿瘤内有限的细胞，肿瘤的定位并不总是成功的。本研究在小鼠黑色素瘤中进行了抗黑色素瘤抗体的不同分布的研究。本研究所建立了两种小鼠同基因单抗(M562和M2590；IgM)。这些单抗是由BALB/C骨髓瘤细胞与同基因B16黑色素瘤细胞诱导的C57BL/6脾细胞融合而成。M2590对人和小鼠黑色素瘤均有反应。除B16小鼠黑色素瘤外，M562对其他肿瘤均无反应。初步研究结果表明，放射性同位素标记的单抗AMAB在荷黑色素瘤小鼠体内有特异性蓄积，并且这些抗体在肿瘤的各个宏观放射自显影上分布不均。将约3.7MBq的1-131标记抗体和1.11MBq的1-125标记抗体注射到同基因小鼠黑色素瘤小鼠体内。1-131标记抗体在制备小鼠标本后一周内出现在胶片上。约3个月后，用双核素技术在放射自显影上观察到小鼠AMAB的不同分布。结果表明，两种不同的AMAb在肿瘤中的优先蓄积是由于针对细胞表面决定簇的抗体所致。因此，多克隆抗体可用于较高的肿瘤摄取率，也可用于放射免疫检测和放射免疫治疗。

This study is to prove the different biodistributions in the tumor using two kinds of antimelanoma antibodies in Vivo.Although scintigraphy with radioisotope labeled monoclonal antibodies to image the tumor has proved to be useful, the localization of the tumor was not always successful, because monoclonal antibodies binds only the limited cells within the tumor.This study was undertaken in the different distributions of antimelanoma antibodies (AMAb),in the mouse melanoma.Two species of murine syngeneic monoclonal AMAb (M562 and M2590; IgM) have been established at our institutions. These monoclonal antibodies were obtained by fusion of BALB/C myeloma and C57BL/6 spleen cells primed with syngeneic B16 melanoma cells. M2590 was reacted to both human and mouse melanomas. M562 showed no reaction for any tumors except B16 mouse melanoma.This initial findings showed that radioisotope labeled monoclonal AMAb was accumulated in melanoma bearing mice specifically, and that these antibodies were distributed inhomogeneously on each macroautoradiogram in the tumors. About 3.7 MBq of 1-131 labeled antibody arid 1.11 MBq of 1-125 labeled antibody were injected into the mice bearing syngeneic mouse melanoma. The distribution of 1-131 labeled antibody was obtained on film within one week after the preparation of mouse specimen. About three months later the different distributions of the mouse AMAb were observed on autoradiogram using the double nuclide technique.The result suggests that preferential accumulations of two different AMAbs in the tumors were owing to the antibodies directed against a determinant on cell surface. The polymonoclonal antibodies, therefore, can be given to nigher tumor uptakes and also useful for radioimmutiodetection and radioimmnunotherapy.