Kobayashi M, Asano H, Hotta T
Second Department of Anatomy, Nagoya University School of Medicine.
Rinsho Ketsueki. 1990 Jul;31(7):946-50.
Peculiar cytoplasmic connection between erythroblasts was observed in the smear preparation of human bone marrow; a pair of erythroblasts in the resting stage was connected by "cytoplasmic bridge" which is very thin and sometimes long compared with the telophase bridge appeared in the usual cytokinesis. Electron microscopy revealed that small amount of microtubules were running along in the cytoplasmic bridge but mid-body was not seen. Plasma membrane about the middle of the bridge bulged to form "bulging ring". Erythroblasts in various differentiating stages were connected by the cytoplasmic bridge and the stage of each pair was almost the same. The occurrence of the cytoplasmic bridge between erythroblasts was evaluated in the smear preparations of human bone marrow with hematological diseases or normal conditions. In the normal bone marrow, the mean value was 8.1 +/- 3.6% (n = 33). In patients suffered from autoimmune hemolytic anemia, it was 4.3 +/- 2.3% (n = 12), aplastic anemia, 3.2 +/- 2.1% (n = 6) and paroxysmal nocturnal hemoglobinuria, 5.0 +/- 1.4% (n = 3). While in the erythroleukemia the occurrence was very low showing 0.2 +/- 0.1% (n = 3) of total erythroblasts. In MDS, RAEB (2.5 +/- 2.4%) and RA (2.9 +/- 2.2+%) showed statistically significant lower occurrence. In the normal bone marrow the occurrence was higher, so the formation of cytoplasmic bridge could be essential for a normal proliferation of erythroblasts.
在人骨髓涂片制备中观察到成红细胞之间存在特殊的细胞质连接；一对处于静止期的成红细胞通过“细胞质桥”相连，与正常胞质分裂时出现的末期桥相比，该细胞质桥非常细，有时还很长。电子显微镜显示，少量微管在细胞质桥中延伸，但未见中间体。桥中部的质膜鼓起形成“鼓胀环”。不同分化阶段的成红细胞通过细胞质桥相连，每对的阶段几乎相同。在患有血液系统疾病或处于正常状态的人骨髓涂片制备中评估了成红细胞之间细胞质桥的发生率。在正常骨髓中，平均值为8.1±3.6%（n = 33）。自身免疫性溶血性贫血患者为4.3±2.3%（n = 12），再生障碍性贫血患者为3.2±2.1%（n = 6），阵发性夜间血红蛋白尿患者为5.0±1.4%（n = 3）。而在红白血病中，发生率非常低，占总幼红细胞的0.2±0.1%（n = 3）。在骨髓增生异常综合征中，难治性贫血伴原始细胞过多（2.5±2.4%）和难治性贫血（2.9±2.2%）的发生率在统计学上显著较低。在正常骨髓中发生率较高，因此细胞质桥的形成可能对成红细胞的正常增殖至关重要。
