(本课题受中国博士后科学基金[中博基1996(2)号文]及国家
自然科学基金(39770334)资助)
摘要目的:根据阵发性睡眠性血红蛋白尿症(PNH)患者骨髓造血干/祖细胞的含量,探讨异常细胞获得造血优势的可能原因。方法:骨髓有核细胞以CD34-FITC及CD59-PE免疫荧光双标记,经流式细胞仪测定不同细胞群内CD34+细胞含量。结果:①正常对照及PNH患者骨髓中的CD34+细胞均分布在“淋巴细胞窗”(A窗)及“原始细胞窗”(D窗)内。②正常对照A窗及D窗内CD34+细胞数分别为(3?701±896)/105个细胞、(11?373±1?574)/105个细胞;PNH患者A窗及D窗内CD34+ 细胞分别为(1?215±749)/105个细胞及(6?420±2?337)/105个细胞,均较正常对照显著减少(P<0.01)。③患者CD59+ 细胞群中CD34+细胞的减少比CD59-细胞群更为显著,A窗及D窗内CD59-细胞群中CD34+细胞分别相当于CD59+细胞群的5.62倍、1.85倍。④正常对照A窗及D窗内CD34+细胞几乎均为CD59+表型(分别为99.2%±1.0%、98.7%±0.8%),而PNH患者A窗及D窗内则都以CD34+CD59- 细胞占据数量优势(分别为79.3%±15.5%、85.9%±7.8%)。结论: PNH患者骨髓中正常及异常造血干/祖细胞含量与正常对照相比,均显著降低,患者正常造血干/祖细胞的减少远较异常者严重,因而异常克隆的造血优势可能是在正常造血严重不足的背景下所形成的一种相对优势。
Analysis of CD34+ cell amounts in normal and abnormal bone marrow cells of patients with paroxysmal nocturnal hemoglobinuriaLi qiang, Zhang Zhinan, Liu Erkun, et al. Department of Hematology, Peking Union Medical College Hospital, CAMS and PUMC, Beijing100730
AbstractObjective:To explore the contributive role of CD34+ cell amount in pathogenesis of clonal dominance in paroxysmal nocturnal hemoglobinuria(PNH). Methods: Bone marrow nuclear cells (BMNCs) were doubly labeled by PE-conjugated anti-CD59 monoclonal antibody ( McAb ) and FITC-conjugated anti-CD34 McAb, and CD34+ cells contained in different cell populations were determined by flow cytometry.Results:① CD34+ cells mainly appeared in window A(containing mainly of lymphocytes) and window D (composed of blasts, other immature cells and monocytes) in both normal controls and PNH patients. ②The numbers of CD34+ cells in normal controls were (3?701±896)/105 cells and (11?373±1?574)/105 cells in window A and window D, respectively. Compared with normal controls, PNH patients possessed significantly decreased number of CD34+ cells [(1?215±749)/105 cells and (6?420±2?337)/105 cells in window A and window D, respectively]. ③In normal controls, nearly all CD34+ cells in windows A and D expressed CD59 antigen (99.2%±1.0% in A and 98.7%±0.8% in D), whereas in PNH patients, the CD34+ cells clearly showed two immunophenotypes of CD34+ CD59+ and CD34+CD59- with the latter being predominant in both window A and window D( CD59- cells constituting 79.3%±15.5% and 85.9%±7.8% of CD34+cells, respectively). ④The amounts of CD34+ cells in CD59+ populations [(463±276)/105 cells in window A and (3?841±1?188)/105 cells in window D] reduced to a greater extent than that in CD59- population [(2?603±2?084)/105 cells in window Aand (7?105±2?739)/105 cells in window D]. Conclusion: Hematopoietic stem/progenitor cells in BMNCs of PNH patients are markedly decreased. Reduction of CD34+ cells in CD59+ cell population is even more obvious than that in CD59- population. The dominance of the abnormal clone in hematopoiesis might be a relative one in the setting of severely impaired normal hematopoiesis.
Key wordsHemoglobinuria,paroxysmalBone marrowHematopoietic stem cellsAntigen,CD59Flow cytometry
阵发性睡眠性血红蛋白尿症(PNH)是造血干细胞克隆病,患者体内正常细胞和异常克隆并存。我们先前的研究表明:PNH患者骨髓单个核细胞的增殖和集落形成能力均较正常对照差,而CD59+的单个核细胞又较CD59-细胞更差[1]。究其原因,是由于PNH异常克隆具有增殖优势,还是由于患者骨髓单个核细胞所含正常造血干/祖细胞减少,尚待研究。由于CD34抗原只选择性地表达于造血干/祖细胞膜上,CD34+细胞可反映体内造血干/祖细胞水平[2],我们测定了PNH患者骨髓正常(CD59+)及异常(CD59-)细胞中CD34+细胞含量并与正常对照比较,以期从造血干/祖细胞含量上探讨PNH患者骨髓中CD59-单个核细胞比CD59+单个核细胞增殖能力更强的原因。
病例和方法
1研究对象正常骨髓7例,3例由髂骨穿刺获取,另4例取自胸科非血液病患者手术切除的肋骨,均经骨髓涂片检查证实其形态学正常。PNH患者7例系我院门诊及住院患者,均为近期(3个月内)有血红蛋白尿发作的患者, 按文献[3]标准确诊,经髂骨穿刺获取骨髓。
2全骨髓有核细胞(BMNCs)制备正常及PNH患者骨髓均经肝素抗凝,低渗溶破红细胞后以0.5%BSA、0.1%NaN3的PBS(pH 7.4)洗涤2次,计数并调整细胞浓度至107/ml。
3免疫荧光双标记取上述细胞悬液0.1ml(106个细胞),先加入非特异性结合阻断试剂A(Miltenyi Biotech公司, Germany),40℃孵育10分钟,然后加入荧光素异硫氰酸酯(FITC)标记的CD34单抗(抗HPCA-2,Becton Dickenson公司, USA),40℃孵育20分钟,以PBS洗涤2次后重悬细胞,再加入荧光素藻红蛋白(PE)标记的CD59单抗(PharMingen公司, USA),40℃孵育30分钟,PBS洗涤2次后,以0.5%多聚甲醛固定。阴性对照管则分别加FITC及PE标记的无关单抗,余步骤同实验管。
4流式细胞仪测定流式细胞仪为Coulter 公司产品(EPICS Elite ESP型)。测定时先以标准荧光微球校准仪器,使各PMT Half CV<2%。各样本测定时均先适当调节前向角散射(FS)及侧向角散射(SS)电压,使骨髓细胞根据FS和SS的不同分三群,分别对此三群细胞设窗为A(淋巴细胞窗)、C(粒细胞窗)、D(原始细胞窗)[4],并测定各窗内细胞CD34及CD59的表达。正常对照及PNH患者骨髓细胞阴性对照管及测定管均用同样条件测定。资料以List mode方式获取,结果以二维点图表示, 每份样品测定2×105个细胞。
结果
1BMNCs的分布A窗内淋巴细胞占90%左右; C窗内粒细胞占95%以上, 主要含晚幼粒、带状核及分叶核细胞; D窗内主要含各系列原始细胞、幼稚细胞及少量单核细胞[4]。
2正常骨髓及PNH患者骨髓CD34+细胞的分布正常骨髓及PNH患者骨髓CD34+细胞均分布于A窗及D窗内,C窗内几乎无CD34+细胞。因此,CD34+ 细胞测定主要在A窗、D窗内进行。
3正常骨髓CD34+细胞正常骨髓A窗内CD34+细胞数为(3?701±896)/105个细胞, CD34+细胞中CD59+表型者占99.2%±1.0%(见图1);D窗内CD34+细胞数为(11?373±1?574)/105个细胞, 约为A窗的2.75倍, CD59阳性率为98.7%±0.8%(见图2)。
