Balduini A, d'Apolito M, Arcelli D, Conti V, Pecci A, Pietra D, Danova M, Benvenuto F, Perotti C, Zelante L, Volinia S, Balduini C L, Savoia A
Department of Biochemistry, IRCCS Policlinico S. Matteo, University of Pavia, Pavia, Italy.
J Thromb Haemost. 2006 Apr;4(4):848-60. doi: 10.1111/j.1538-7836.2006.01802.x.
Megakaryopoiesis represents a multi-step, often unclear, process leading to commitment, differentiation, and maturation of megakaryocytes (MKs) that release platelets.
To identify the novel genes that might help to clarify the molecular mechanisms of megakaryocytopoiesis and be regarded as potential candidates of inherited platelet defects, global gene expression of hematopoietic lineages was carried out.
Human cord blood was used to purify CD34+ stem cells and in vitro expand CD41+ cells and burst-forming unit-erythroid (BFU-E). We investigated the expression profiles of these three hematopoietic lineages in the Affymetrix system and selected genes specifically expressed in MKs by comparing transcripts of the different lineages using the dchip and pam algorithms.
A detailed characterization of MK population showed that 99% of cells expressed the CD41 antigen whereas 73% were recognizable as terminally differentiated fetal MKs. The profile of these cells was compared with that of CD34+ cells and BFU-E allowing us to select 70 transcripts (MK-core), which represent not only the genes with a well-known function in MKs, but also novel genes never detected or characterized in these cells. Moreover, the specific expression was confirmed at both RNA and protein levels, thus validating the 'MK-core' isolated by informatics tools.
This is a global gene expression that for the first time depicts a well-characterized population of cord blood-derived fetal MKs. Novel genes have been detected, such as those encoding components of the extracellular matrix and basal membrane, which have been found in the cytoplasm of Mks, suggesting that new physiological aspects of MKs should be studied.
巨核细胞生成是一个多步骤的过程，通常并不明确，该过程导致产生血小板的巨核细胞（MK）的定向分化和成熟。
为了鉴定可能有助于阐明巨核细胞生成分子机制并被视为遗传性血小板缺陷潜在候选基因的新基因，我们对造血谱系进行了全基因组表达分析。
使用人脐带血纯化CD34 +干细胞，并在体外扩增CD41 +细胞和红系爆式集落形成单位（BFU-E）。我们在Affymetrix系统中研究了这三种造血谱系的表达谱，并通过使用dchip和pam算法比较不同谱系的转录本，选择了在MK中特异性表达的基因。
对MK群体的详细表征显示，99%的细胞表达CD41抗原，而73%可识别为终末分化的胎儿MK。将这些细胞的表达谱与CD34 +细胞和BFU-E的表达谱进行比较，使我们能够选择70个转录本（MK核心），它们不仅代表在MK中具有已知功能的基因，还代表在这些细胞中从未检测到或表征过的新基因。此外，在RNA和蛋白质水平均证实了特异性表达，从而验证了通过信息学工具分离出的“MK核心”。
这是首次对特征明确的脐带血来源胎儿MK群体进行的全基因组表达分析。已检测到新基因，例如编码细胞外基质和基底膜成分的基因，这些基因已在MK的细胞质中发现，这表明应研究MK的新生理特性。
