Okuda K, Kanamaru A, Ueda E, Kitani T, Okada N, Okada H, Kakishita E, Nagai K
Second Department of Internal Medicine, Hyogo College of Medicine, Nishinomiya City, Japan.
Exp Hematol. 1990 Nov;18(10):1132-6.
Decay-accelerating factor (DAF), a complement-regulating glycoprotein, has been shown to be expressed on hematopoietic progenitors and their progeny cells in normal individuals but not on abnormal cells in patients with paroxysmal nocturnal hemoglobinuria (PNH). Fluorescence histograms of bone marrow cells showed the heterogeneity of DAF expression on their cell membranes, suggesting mixed hematopoietic cell populations in PNH. We have previously shown that DAF is a maturational protein expressed on normal hematopoietic cells. In order to elucidate the relationship between DAF expression and cell maturity in PNH, we fractionated bone marrow cells according to amount of DAF and cultured these cells in methylcellulose for clonal assay of erythroid burst-forming units (BFU-E) and granulocyte-macrophage colony-forming units (CFU-GM), followed by reanalysis of DAF expression on their progeny. The matured cells from the bursts/colonies in cultures with DAF-negative PNH marrow cells had no or little DAF, but those grown from DAF-positive PNH progenitors showed nearly as much of this factor as those grown from normal progenitors. These results clearly indicate that there are at least two distinct populations of hematopoietic progenitors with respect to the membrane expression of DAF and that abnormalities occur at the level of the stem cell in PNH.
衰变加速因子（DAF）是一种补体调节糖蛋白，已证实在正常个体的造血祖细胞及其子代细胞上表达，但在阵发性夜间血红蛋白尿（PNH）患者的异常细胞上不表达。骨髓细胞的荧光直方图显示其细胞膜上DAF表达的异质性，提示PNH中存在混合造血细胞群。我们之前已表明DAF是一种在正常造血细胞上表达的成熟蛋白。为了阐明PNH中DAF表达与细胞成熟之间的关系，我们根据DAF的量对骨髓细胞进行分级，并将这些细胞在甲基纤维素中培养，用于红系爆式集落形成单位（BFU-E）和粒-巨噬细胞集落形成单位（CFU-GM）的克隆分析，随后重新分析其子代细胞上的DAF表达。用DAF阴性的PNH骨髓细胞培养的爆式集落/集落中的成熟细胞没有或几乎没有DAF，但从DAF阳性的PNH祖细胞生长而来的细胞显示出的该因子与从正常祖细胞生长而来的细胞几乎一样多。这些结果清楚地表明，就DAF的膜表达而言，至少存在两种不同的造血祖细胞群，并且PNH中干细胞水平发生了异常。
