目的以多发性骨髓瘤(MM)细胞株 RPMI 8226异体移植小鼠为动物模型,评估抗脑源性神经营养因子(BDNF)单克隆抗体(单抗)存体内的抗肿瘤活性。方法选择糖尿病抵抗/重症联合免疫缺陷(NOD/SCID)小鼠,皮下注射 RPMI 8226细胞建立骨髓瘤细胞异体移植动物模型。以20μg/只的 BDNF 单抗剂量于接种肿瘤细胞后第1、2、3天腹腔内注射或者以100 μg/只的剂量于检测到瘤体后每周1次腹腔内注射。采用组织学方法检测瘤细胞的形态特征,免疫化学染色法分析瘤组织的微血管密度(MVD)。用~3H-TdR 掺入法和 Matrigel 网状结构形成实验分别检测 BDNF 单抗对 RPMI8226细胞体外增殖和 PRMI 8226细胞诱导的内皮细胞血管新生的影响。结果在 NOD/SCID 小鼠体内建立的骨髓瘤细胞异体移植动物模型,其皮下种植的成瘤率高,具有多种与浆细胞瘤相似的病理学特征。未治疗组小鼠皮下注射 RPMI 8226细胞后(20±2)d 可检测到皮下肿瘤;接种肿瘤细胞后连续3 d 注射20 μg BDNF 单抗的治疗组,小鼠平均无肿瘤生存期延长为(30±6)d,而相应埘照抗体治疗组无肿瘤生存期为(22±3)d,与末治疗组相比差异无统计学意义;同时,其中位存活时间为(57±7)d,与相应的对照抗体治疗组[(48±4)d]相比明显延长(P<0.05);治疗组小鼠自然死亡时肿瘤体积为(157.9±21.6)mm~3,较对照抗体组[(405.5±35.2)mm~3]明显缩小(P<0.05)。对于接种肿瘤细胞后第27天起每周注射1次 BDNF 单抗(100 μg/次)的治疗组,肿瘤的生长亦受到部分抑制,相应对照抗体组与未治疗组相比肿瘤生长差异无统计学意义;同时在 BDNF 单抗治疗组瘤体的组织切片中,观察到部分瘤细胞出现凋亡的形态学表现,坏死区被纤维结缔组织浸润。未治疗组瘤块的 MVD 为38个/0.216 mm~2,BDNF 单抗治疗组(100 μg/次)MVD 为11个/0.216 mm~2,与未治疗组相比对照抗体治疗组瘤块的 MVD 没有明显下降(35个/0.216 mm~2)(P>0.05)。在体外,BDNF 单抗可显著抑制 RPMI8226细胞的增殖和其诱导的内皮细胞网状结构形成(抑制率为68.2%),而相应的对照抗体却无此效应。结论 BDNF 单抗可抑制皮下浆细胞瘤的生长和血管新生,BDNF 是治疗 MM 的潜在靶点。 OBJECTIVE: To evaluate the antitumor activity of multiple myeloma (MM) cell line RPMI 8226 xenografted mice in vivo using anti-brain derived neurotrophic factor (BDNF) monoclonal antibody (mAb). Methods Mouse models of diabetic resistance / severe combined immunodeficiency (NOD / SCID) were selected and subcutaneously injected with RPMI 8226 cells to establish an animal model of myeloma xenograft. The mice were inoculated intraperitoneally with the dose of 20μg / mouse BDNF monoclonal antibody at 1, 2, 3 days after the tumor cells were inoculated or intraperitoneally once a week after the tumors were detected at the dose of 100 μg / body. The morphological features of tumor cells were detected by histological method, and the microvessel density (MVD) of tumor tissues was analyzed by immunochemical staining. 3H-TdR incorporation and Matrigel reticular formation assay were used to detect the effect of BDNF monoclonal antibody on the proliferation of RPMI8226 cells and the endothelial cell angiogenesis induced by PRMI 8226 cells. Results The animal model of myeloma cell xenotransplantation established in NOD / SCID mice had a high rate of tumorigenesis with subcutaneous implantation and had many pathological features similar to those of plasmacytoma. Subcutaneous injection of RPMI 8226 cells in untreated group (subcutaneous) detected subcutaneous tumors (20 ± 2) days after inoculation of tumor cells and injection of 20 μg BDNF monoclonal antibody for 3 consecutive days. The mean tumor-free survival of mice was ( 30 ± 6) d, while the corresponding antibody-treated group had no tumor survival (22 ± 3) d, which was not significantly different from the last treatment group; mean survival time was (57 ± 7) d (P <0.05). Compared with the control antibody group [(48 ± 4) d], the tumor volume in the treatment group was (157.9 ± 21.6) mm ~ 3 compared with the control antibody group [ (405.5 ± 35.2) mm ~ 3] (P <0.05). Tumor growth was also partially inhibited by treatment with BDNF monoclonal antibody (100 μg once weekly) starting on day 27 after tumor cell inoculation, and there was no statistical difference in tumor growth between the corresponding control antibody group and the untreated group In the meantime, in the histological sections of the tumors treated with BDNF monoclonal antibody, morphological features of some tumor cells were observed. The necrotic area was infiltrated by fibrous connective tissue. The MVD in the untreated group was 38 /0.216 mm2, while the MVD in the BDNF-treated group (100 μg / time) was 11 /0.216 mm2 compared with the untreated group MVD was not significantly decreased (35 / 0.216 mm ~ 2) (P> 0.05). In vitro, BDNF mAb significantly inhibited the proliferation of RPMI8226 cells and the endothelial cell reticulum formation induced by it (the inhibition rate was 68.2%), while the corresponding control antibody had no such effect. Conclusion BDNF monoclonal antibody can inhibit the growth and angiogenesis of subcutaneous plasmacytoma, BDNF is a potential target for the treatment of MM.