原子力显微镜观测CD34阳性细胞的形貌结构

目的用原子力显微镜观测正常人及表达CD34抗原的白血病细胞表面的形貌结构,并比较两者的异同。方法从健康人和M2b型白血病患者各3例骨髓标本中分离出单个核细胞,利用免疫磁柱法纯化CD34 细胞,流式细胞仪检测其纯度。用光学显微镜和原子力显微镜进行观测。结果光学显微镜下两种来源的CD34 细胞形貌相似。原子力显微镜下可观测到细胞表面有许多微绒毛突起,表面粗糙度在不同来源细胞内部呈正态分布,正常人及表达CD34抗原的白血病细胞表面在平均粗糙度、均方根粗糙度方面有显著差别。结论M2b型CD34 白血病细胞较正常CD34 细胞表面皱折程度显著降低。

Surface morphology of CD34+ cells under atomic force microscope

Objective To observe the difference in surface morphology and structure between CD34 cells from normal humansubjects and from patients with leukemia. Methods Bone marrow mononuclear cells from 3 normal human subjects and 3patients with M2b leukemia were collected by Percoll gradient centrifugation, followed by purification of CD34 cells bymeans of immunomagnetic bead separation (MiniMAC) and examination with flow cytometry. The morphology of the cellswere then observed with optical and atomic force microscope (AFM) in air. Results No significant difference was identifiedbetween the two cells under optical microscope. With atomic force microscope, numerous microvilli were observed on the surfaceof CD34 cells, and the normal cells and those from the leukemic patients showed significant difference in terms of the roughness ofthe cell surface. Conclusion Normal CD34 cells have more rough and erosive surface structure than leukemic CD34 cells (M2b).