青春双歧杆菌DM8504菌株对小鼠体内HCa-F_(25)/16A_3-F肿瘤细胞抑制作用的初步研究

STUDY ON THE ANTITUMOR EFFECT MECHANISM OF BIFIDOBACTERIUM ADOLESCENTIS DM8504 STRAIN IN HCa-F 25 /16A 3-F TUMOR-BEARING MICE

本实验应用加热处死的青春双歧杆菌ＤＭ８５０４菌株皮下注射荷瘤ＨＣａ－Ｆ２５／１６Ａ３－Ｆ肿瘤的ＢＡＬＢ／ｃ小鼠，酶联法测定小鼠体内ＴＮＦ－α、ＩＬ－６的含量，ＴＵＮＥＬ法及电镜观察肿瘤组织中是否有凋亡细胞的存在。实验结果指出：双歧杆菌能提高荷瘤小鼠体内ＴＮＦ－２的含量，较对照组明显升高，但ＩＬ－６的含量处理组与对照组之间无显著性差异。ＴＵＮＥＬ法除观察到不同程度的坏死组织外，未见到散在的凋亡的肿瘤细胞，电镜观察与ＴＵＮＥＬ结果相一致，肿瘤细胞呈现坏死细胞的超微结构，未见凋亡细胞所具有的典型的形态特征。结果提示：双歧杆菌通过调节机体的免疫系统发挥抗肿瘤的作用，其对ＨＣａ－Ｆ２５／１６Ａ３－Ｆ肿瘤细胞的杀伤是通过坏死的方式实现的。

In present study,heat-killed cells of B adolescentis DM8504 strain was injected subcutaneously in HCa-F 25 /16A 3-F tumor-bearing BALB/C mice.The level of production of TNF-α and IL-6 in the serum of the tumor-beraing mice was measured by ELISA. Apoptosis in tumor tissue was detected by TUNEL and electronmicroscopic observation.The results indicated that TNF-α production was increased in tumor-bearing mice injected with B adolescentis DM8504 strain,but the level of IL-6 didn't reach a statistical significance.No apoptotic cells were observed throughout the tumor tissue except different extent of adjoing necrotic ares by TUNEL method.Electronmicroscopic observation showed similar result.Tumor cells were characterized by necrotic cellar ultrastructure not by typical morphology of apoptotic cells.It demenstrated that B. adolescentis DM8504 acts in tumor-bearing mice by regulation of host immunoresponscs and HCa-F 25 /16A 3-F tumor cells may be killed through necrosis.