目的： 研究香菇多糖（lentinan， LNT）对急性髓细胞性白血病（acute myeloid leukemia, AML）患者树突状细胞（dendritic cell，DC）成熟及功能的影响，探索白血病免疫治疗的新途径。 方法： 分离AML完全缓解期患者（AML-complete remission，AML-CR）的骨髓单个核细胞（bone marrow mononuclear cell，BMC），用GM-CSF和IL-4诱导7 d培养DC，然后分组：LPS阳性对照组、LNT实验组和对照组。培养48 h后以瑞氏－吉姆萨(Wright-Giemsa)染色观察各组DC形态，流式细胞术检测各组DC表面分子CD80、CD83、CD86、CD1a和HLA-DR的表达，ELISA法检测各组DC上清液中IL-12的水平。免疫磁珠法分离AML-CR患者经LNT治疗后的外周血DC，ELISA法检测治疗后DC上清液中IL-12的水平。 结果： 体外实验中，LNT处理后DC呈典型树突状形态；其表面分子CD80、CD83、CD86、CD1a及HLA-DR的表达上调（P<0.05）；DC分泌IL-12较阴性对照组显著增高（P<0.05），且呈LNT浓度依赖性。患者体内试验结果显示，LNT治疗后AML患者的DC上清液中IL-12分泌水平较治疗前显著提高（P<0.05）。 结论： LNT在体内外均能促进AML患者的DC成熟和增强DC功能。

Objective: To study the effects of lentinan (LNT) on maturation and function of dendritic cells (DCs) of acute myeloid leukemia (AML) patients, so as to explore new ways for leukemia immunotherapy. Methods: Bone marrow mononuclear cells (BMCs) were isolated from AML complete remission (AML-CR) patients, and were induced to differentiate into DCs by GM-CSF and IL-4 for 7 d. DCs were then divided into 3 groups: LPS positive control group, LNT group, and control group. After 48 h, the morphology of DCs was observed by Wright-Giemsa staining in different groups; CD80, CD83, CD86, CD1α, and HLA-DR expressions on DCs were examined by flow cytometry assay; and IL-12 production was determined by ELISA. DCs of AML patients were isolated from human peripheral blood mononuclear cells (PBMC) by magnetic cell sorting (MACS) after LNT therapy, and the concentration of IL-12 in DC supernatants was determined by ELISA. Results: In vitro, LNT-treated DCs showed a typical DC morphology; it concentration-dependently increased the expressions of CD80, CD83, CD86, CD1a and HLA-DR (P＜0.05) and level of IL-12 compared with the control group (P＜0.05). In vivo, IL-12 in the supernatant of DCs of AML patients after LNT therapy was significantly higher than that of untreated patients (P＜0.05). Conclusion: LNT can promote maturation and function of DCs from AML patients in vivo and in vitro, exrting its anti-tumor effect.

甘肃省科技支撑计划项目(No.0804NKCA115)