Wu Chong-Yang, Zhang Lian-Sheng, Zhang Yu-Fang, Chai Ye, Yi Liang-Cai, Song Fei-Xue
Department of Hematology and Oncology, The Second Affilated Hospital, Lanzhou University, Lanzhou, Gansu, 730030, P.R.China.
Ai Zheng. 2005 Apr;24(4):425-31.
BACKGROUND & OBJECTIVE: Interferon-alpha (IFN-alpha), an important immunoregulatory cytokine, has been widely used in treating virus hepatitis, lymphoma, and chronic myeloid leukemia (CML), and showed evident effect, but the mechanism is unclear. Dendritic cells (DCs), specialized antigen-presenting cells (APCs), play a pivotal role in activating initial T cells, and maintaining cell immune responses. Does the efficiency of IFN to CML relate to the DCs induced by IFNy What kind of effect do DCs have on IFN therapy for CMLy Up to now, few researches are available. This study aimed to observe whether the DCs were induced through culturing bone marrow mononuclear cells (BMMNCs) of CML in vitro, investigate the mechanism of IFN-alpha therapy for CML, and then provide a new strategy for clinical therapy.
BMMNCs were obtained from blood of CML patients by Ficoll-Paque density gradient centrifugation, and induced with IFN-alpha and granulocyte-macrophage colony-stimulating factor (GM-CSF) (IFN-alpha/ GM-CSF group), or interleukin-4 (IL-4) and GM-CSF (IL-4/ GM-CSF group), or IFN-alpha, GM-CSF, and IL-4 (IFN-alpha/GM-CSF/IL-4 group) for 7 days. Morphology of BMMNCs was observed under transmissional and optical microscope. The phenotypes [CD1a, CD83, CD86, human leukocyte antigen (HLA)-ABC, HLA-DR, CD54] were assayed by flow cytometry (FCM). The mixed lymphocyte reaction(MLR) of DCs was evaluated by MTT assay.
After inducements, BMMNCs showed typical dendritic projections, and highly expressed CD1a, CD83, CD86, HLA-ABC, HLA-DR, and CD54. Positive rates of HLA-ABC and HLA-DR were higher in IFN-alpha/ GM-CSF group and IFN-alpha/GM-CSF/IL-4 group than in IL-4/ GM-CSF group (P<0.05). Positive rate of CD86 and MLR were the highest in IFN-alpha/GM-CSF/IL-4 group (P<0.05). Positive rates of DC antigens and MLR in IFN-resistant group were significantly lower than those in newly diagnosed group and IFN-sensitive group (P<0.05), but positive rate of CD86 and MLR have no significant difference among 3 groups in the presence of IFN-alpha/GM-CSF/IL-4 (P>0.05).
The BMMNCs of CML cultured in the presence of IFN-alpha and other cytokines can be induced into DCs with morphologic and immunophenotypic characteristics, overexpresses major histocompatibility complex (MHC) molecules, co-stimulatory molecules, and adhesion molecules, and have enhancing MLR. The possible mechanism of IFN-alpha therapy for CML may be relate to DCs.
α干扰素（IFN-α）作为一种重要的免疫调节细胞因子，已广泛应用于病毒性肝炎、淋巴瘤及慢性粒细胞白血病（CML）的治疗，疗效显著，但作用机制尚不清楚。树突状细胞（DCs）作为专职抗原呈递细胞（APCs），在激活初始T细胞及维持细胞免疫反应中起关键作用。IFN对CML的疗效是否与IFN诱导的DCs有关？DCs对CML的IFN治疗有何影响？目前相关研究较少。本研究旨在观察体外培养CML患者骨髓单个核细胞（BMMNCs）能否诱导产生DCs，探讨IFN-α治疗CML的机制，为临床治疗提供新策略。
采用Ficoll-Paque密度梯度离心法从CML患者血液中获取BMMNCs，分别用IFN-α和粒细胞巨噬细胞集落刺激因子（GM-CSF）（IFN-α/GM-CSF组）、白细胞介素-4（IL-4）和GM-CSF（IL-4/GM-CSF组）、IFN-α、GM-CSF和IL-4（IFN-α/GM-CSF/IL-4组）诱导7天。在透射电镜和光学显微镜下观察BMMNCs的形态。采用流式细胞术（FCM）检测细胞表型[CD1a、CD83、CD86、人类白细胞抗原（HLA）-ABC、HLA-DR、CD54]。采用MTT法评估DCs的混合淋巴细胞反应（MLR）。
诱导后，BMMNCs呈现典型的树突状突起，高表达CD1a、CD83、CD86、HLA-ABC、HLA-DR和CD54。IFN-α/GM-CSF组和IFN-α/GM-CSF/IL-4组的HLA-ABC和HLA-DR阳性率高于IL-4/GM-CSF组（P<0.05）。IFN-α/GM-CSF/IL-4组的CD86阳性率和MLR最高（P<0.05）。IFN耐药组的DC抗原阳性率和MLR显著低于初诊组和IFN敏感组（P<0.05），但在IFN-α/GM-CSF/IL-4存在的情况下，3组的CD86阳性率和MLR无显著差异（P>0.05）。
在IFN-α等细胞因子存在的情况下培养的CML患者BMMNCs可被诱导为具有形态和免疫表型特征的DCs，过表达主要组织相容性复合体（MHC）分子、共刺激分子和黏附分子，并增强MLR。IFN-α治疗CML的可能机制可能与DCs有关。
