D'Arena G, Cascavilla N, Musto P, Greco M, Di Mauro L, Carella A M, Dello Iacono N, Carotenuto M
Division of Hematology, IRCCS Casa Sollievo della Sofferenza Hospital, Rotondo, Italy.
Haematologica. 1996 May-Jun;81(3):216-23.
Hematopoietic progenitor cells (HPC), identified by expression of the CD34 surface antigen, show morphological and phenotypic heterogeneity in bone marrow (BM) and peripheral blood (PB).
CD34+ HPC subpopulations present in 18 PB leukaphereses after high-dose chemotherapy in cancer patients and in 11 BM samples from patients with stage IA lymphoma were characterized. In order to identify CD34+ HPC subsets within these two compartments, the expression of lineage- or activation-associated antigens and the c-kit gene product (CD117) was studied by flow cytometry, using a large panel of monoclonal antibodies (MoAb) in double labelling.
We observed a higher proportion of CD34+/CD13+ and CD34+/CD33+ cells (myeloid commitment) in harvested leukapheresis products than in BM. On the contrary, a higher percentage of CD34+/CD10+ and CD34+/CD19+ cells (B-lymphoid commitment) was found in BM. The percentage of the most immature subset of CD34+ HPC (CD38- and HLA-DR-) was also higher in BM than in mobilized PB. No differences in proportions were found with respect to the expression of CD14, CD15, CD45RA (myeloid commitment), CD2, CD5, CD7 (T-lymphoid commitment), CD117, CD71 and CD45RO antigens. In terms of absolute values, however, significantly higher amounts of CD34+ HPC co-expressing CD13, CD33, CD5, CD7, CD71, CD117, CD45RA, CD45RO were detected in leukaphereses than in BM. The absolute number of immature HPC (CD34+/CD38- and CD34+/HLA-Dr-) was also significantly increased in mobilized PB.
Our data confirm the heterogeneous phenotypic profile of HPC, thus supporting the hypothesis that different CD34+ subpopulations may have clinical relevance on the rapidity and long-term durability of engraftment in patients who undergo high-dose chemotherapy followed by rescue with HPC. We also demonstrated that mobilized PB is a particularly rich source of both primitive and committed HPC, more than BM.
通过CD34表面抗原的表达鉴定的造血祖细胞（HPC）在骨髓（BM）和外周血（PB）中表现出形态和表型的异质性。
对癌症患者大剂量化疗后18份PB白细胞单采产物以及11份IA期淋巴瘤患者BM样本中的CD34⁺ HPC亚群进行了特征分析。为了鉴定这两个区室中的CD34⁺ HPC亚群，采用大量单克隆抗体（MoAb）进行双标记，通过流式细胞术研究谱系或激活相关抗原以及c-kit基因产物（CD117）的表达。
我们观察到，采集的白细胞单采产物中CD34⁺/CD13⁺和CD34⁺/CD33⁺细胞（髓系定向）的比例高于BM。相反，BM中CD34⁺/CD10⁺和CD34⁺/CD19⁺细胞（B淋巴细胞定向）的百分比更高。BM中最不成熟的CD34⁺ HPC亚群（CD38⁻和HLA-DR⁻）的百分比也高于动员的PB。在CD14、CD15、CD45RA（髓系定向）、CD2、CD5、CD7（T淋巴细胞定向）、CD117、CD71和CD45RO抗原的表达方面，未发现比例差异。然而，就绝对值而言，白细胞单采中共同表达CD13、CD33、CD5、CD7、CD71、CD117、CD45RA、CD45RO的CD34⁺ HPC数量明显高于BM。动员的PB中未成熟HPC（CD34⁺/CD38⁻和CD34⁺/HLA-Dr⁻） 的绝对数量也显著增加。
我们的数据证实了HPC的异质表型特征，从而支持了这样的假设，即不同的CD34⁺亚群可能与接受大剂量化疗后用HPC进行挽救的患者植入的速度和长期持久性具有临床相关性。我们还证明，动员的PB是原始和定向HPC的特别丰富来源，比BM更丰富。
