Akashi Koichi
Department of Cancer Immunology and AIDS, Dana-Farber Cancer Institute, Boston, Massachusetts 02115, USA.
Ann N Y Acad Sci. 2007 Jun;1106:76-81. doi: 10.1196/annals.1392.009. Epub 2007 Mar 14.
A hierarchical hematopoietic developmental tree has been proposed based on the result of prospective purification of lineage-restricted progenitors. For more detailed mapping for hematopoietic stem cell (HSC) commitment, we tracked the expression of PU.1, a major granulocyte/monocyte (GM)- and lymphoid-related transcription factor, from the HSC to the myelolymphoid progenitor stages by using a mouse line harboring a knockin reporter for PU.1. This approach enabled us to find a new progenitor population committed to GM and lymphoid lineages within the HSC fraction. This result suggests that there should be another developmental pathway independent of the conventional one with myeloid versus lymphoid bifurcation, represented by common myeloid progenitors and common lymphoid progenitors, respectively. The utilization of the transcription factor expression as a functional marker might be useful to obtain cartography of the hematopoietic development at a higher resolution.
基于谱系受限祖细胞的前瞻性纯化结果，有人提出了一种分层造血发育树。为了更详细地绘制造血干细胞（HSC）的定向分化图谱，我们利用携带PU.1基因敲入报告基因的小鼠品系，追踪了从造血干细胞到骨髓淋巴细胞祖细胞阶段的PU.1（一种主要的粒细胞/单核细胞（GM）和淋巴细胞相关转录因子）的表达情况。这种方法使我们能够在造血干细胞部分中发现一个新的定向分化为GM和淋巴细胞谱系的祖细胞群体。这一结果表明，应该存在另一条独立于传统发育途径的发育路径，传统途径分别以常见髓系祖细胞和常见淋巴细胞祖细胞为代表，呈现髓系与淋巴系的分支。利用转录因子表达作为功能标记可能有助于以更高分辨率获得造血发育图谱。
