Mukai M, Ando K, Koike S, Nagao K, Isono K
Gan To Kagaku Ryoho. 1986 Dec;13(12):3432-5.
Optimal timing of topical administration of OK-432 and TCD50 were studied using weakly immunogenic and radioresistant C3H mouse fibrosarcoma (NFSa). The mechanism of action of this combined therapy was examined histologically and electron microscopically. Topical administration of OK-432 was performed from 2 days before irradiation to 7 days after irradiation and tumor volumes on the 20th day after irradiation were compared with a control group given radiation alone. Significant difference was observed only in the group which was given OK-432 just after irradiation. The TCD50 of the combined therapy of radiation with topical administration of OK-432, 4 KE which was given just after irradiation was 64.5 Gy and that of radiation alone was 83.5 Gy. Combined therapy shifted the TCD50 curve about 20Gy to the left. Histological examination of the tumor on the 6th day after combined therapy showed marked degeneration and necrosis of tumor cells with marked infiltration of lymphocytes. These lymphocytes were electron microscopically seen surrounding not only damaged cells, but also apparently active tumor cells. We postulate the latter cells had a tendency to be degenerative. This phenomenon suggests that lymphocytes recognize as foreign these tumor cells which are apparently active but some what damaged by radiation.
使用弱免疫原性和抗辐射的C3H小鼠纤维肉瘤（NFSa）研究了OK-432和TCD50局部给药的最佳时机。通过组织学和电子显微镜检查了这种联合治疗的作用机制。从照射前2天至照射后7天进行OK-432的局部给药，并将照射后第20天的肿瘤体积与仅接受辐射的对照组进行比较。仅在照射后立即给予OK-432的组中观察到显著差异。照射后立即给予4 KE的OK-432局部给药与辐射联合治疗的TCD50为64.5 Gy，单独辐射的TCD50为83.5 Gy。联合治疗使TCD50曲线向左移动了约20 Gy。联合治疗后第6天肿瘤的组织学检查显示肿瘤细胞明显变性和坏死，伴有淋巴细胞明显浸润。电子显微镜观察到这些淋巴细胞不仅围绕受损细胞，还围绕明显活跃的肿瘤细胞。我们推测后者细胞有退化的倾向。这种现象表明淋巴细胞将这些明显活跃但受到辐射一定程度损伤的肿瘤细胞识别为外来细胞。
