ERYTHROID CELLS AND HEMOGLOBINS OF CHICK-EMBRYO
ERYTHROID CELLS AND HEMOGLOBINS OF CHICK-EMBRYO
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DOI：
10.1098/rstb.1973.0050
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发表时间：
1973-01-01
期刊：
影响因子：
--
通讯作者：
INGRAM, VM
中科院分区：
文献类型：
--
作者：
BRUNS, GAP;INGRAM, VM
小鸡胚胎发育过程中产生的红系细胞类型的变化与胚胎中发现的血红蛋白类型的变化有关。原始红系细胞是2-5天胚胎中仅有的红细胞。第一批可识别的未成熟的最终红系细胞在5-6天出现在胚胎循环中，并逐渐取代原始细胞，这样到14-16天，原始细胞占循环中的红系细胞的比例不到1%。原始红细胞生成与最终的红细胞生成有显著的不同。在2至16天的任何一个时间点，根据形态标准，所有分离的原始细胞似乎都处于相同的成熟阶段，尽管观察到细胞大小的变化，但对于单个成熟阶段，小细胞并不比中等大小的细胞更成熟，大细胞也不比中或小细胞成熟得少。成熟的原始红系细胞在哺乳动物的红系系统中经历红系成熟特征的细胞结构的渐进性变化，但作为一个统一的细胞群体。从2日龄至5日龄胚胎的原始红系细胞中分离得到的血红蛋白，经聚丙烯酰胺凝胶电泳法鉴定为两种组分，即血红蛋白E和血红蛋白P。6~7天，当第一批血红素化的未成熟红系细胞出现在胚胎循环中时，在红系细胞的裂解物中观察到两种新的血红蛋白成分。这两种新的血红蛋白成分在电泳学和免疫学上与成年鸡的两种血红蛋白成分--血红蛋白A和血红蛋白D完全相同。在胚胎循环中，由于确定的红系细胞取代原始红细胞，血红蛋白A和D的数量增加并取代了血红蛋白P。在原始细胞含量低于1%的16天胚胎的红系细胞裂解液中，免疫检测不到血红蛋白P。在晚期胚胎的红系细胞裂解物中，几乎没有原始红细胞，在pH 10.3的聚丙烯酰胺凝胶中，始终观察到少量的血红蛋白，与血红蛋白E的电泳性相似。在pH 8.9的聚丙烯酰胺凝胶上，在Sephadex G-100柱上，在不同孔隙率的聚丙烯酰胺凝胶上，该组分与血红蛋白E不同，并且通过二维免疫扩散显示与血红蛋白E只有部分相同的反应。这种血红蛋白成分，即血红蛋白H，在12天胚胎的裂解液中可以检测到，在8天的胚胎裂解液中免疫检测到。在成年鸡中没有观察到血红蛋白H。在鸡胚胎发育过程中，从原始的红系细胞向最终的红系细胞的转变与三种新的血红蛋白的合成有关，这三种新的血红蛋白是两个成人的血红蛋白和血红蛋白H。根据凝胶扫描峰值质量的比率确定成年鸡的血红蛋白D/A的比率为0.30。当血红蛋白D和A第一次出现在6-7天胚胎的红系细胞裂解物中时，血红蛋白D/A比率约为0.9。裂解产物的D/A比在16~18天时降至0.5，此时胚胎中99%的红系细胞是成熟的、确定的红细胞。然而，0.5至20日龄的晚期胚胎和雏鸡的裂解产物的血红蛋白D/A比始终大于成年鸡的血红蛋白。…说，鸡胚胎和幼鸡的最终红细胞似乎在至少两个方面与成年鸡的最终细胞不同
The changes in the types of erythroid cells produced during embryogenesis of the chick have been correlated with the changes in the types of haemoglobins found in the embryo. Primitive erythroid cells constitute the only red blood cells of 2- to 5-day embryos. The first recognizable immature definitive erythroid cells appear in the embryonic circulation at 5 to 6 days and progressively replace the primitive cells, such that by 14 to 16 days the primitive cells constitute less than 1 % of the circulating erythroid cells. Primitive erythropoiesis is strikingly different from definitive erythropoiesis. At any one time point between 2 and 16 days, all of the isolated primitive cells appear, by morphological criteria, to be at the same stage of maturation, and, although variation in cell size is observed, for an individual maturation stage, the small cells are not more mature than the medium-size cells, nor are the large cells less mature than the medium or small cells. Maturing primitive erythroid cells undergo the progressive changes in cell structure characteristic of erythroid maturation in mammalian erythropoietic systems, but do so as a uniform cell population. Haemoglobin, isolated from primitive erythroid cells of 2- to 5-day embryos, shows two components on polyacrylamide gel electrophoresis, haemoglobin E and haemoglobin P. The haemoglobin E/P ratio is constant in lysates from 2- to 5-day embryos. A t 6 to 7 days when the first haemoglobinized immature definitive erythroid cells appear in the embryonic circulation, two new haemoglobin components are observed in lysates of erythroid cells. These two new haemoglobin components are electrophoretically and immunologically identical to the two haemoglobin components of adult chickens, haemoglobins A and D. As the definitive erythroid cells replace the primitive erythrocytes in the embryonic circulation, the haemoglobins A and D increase in amount and replace haemoglobin P. Haemoglobin P cannot be detected immunologically in erythroid cell lysates from 16-day embryos which contain less than 1 % primitive cells. In erythroid cell lysates from late embryos, which contained few, if any, primitive erythrocytes, a minor haemoglobin, electrophoretically similar to haemoglobin E on pH 10.3 polyacrylamide gels, is consistently observed. This component differs from haemoglobin E on pH 8.9 polyacrylmide gels, on Sephadex G-100 columns, on polyacrylamide gels of different porosities, and shows a reaction of only partial identity with haemoglobin E by two-dimensional immunodiffusion. This haemoglobin component, haemoglobin H, is detectable electrophoretically in lysates from 12-day embryos and immunologically in lysates from 8-day embryos. Haemoglobin H has not been observed in adult chickens. The switch from the production of primitive to definitive erythroid cells during development of the chick embryo is associated with the initiation of synthesis of three new haemoglobins, the two adult haemoglobins and haemoglobin H. The haemoglobin D /A ratio of adult chicken haemoglobin, determined from the ratio of gel scan peak masses, is 0.30. When haemoglobins D and A first appear in erythroid cell lysates from 6- to 7-day embryos, the haemoglobin D /A ratio is about 0.9. T he D/A ratio of lysates falls to 0.5 by 16 to 18 days, a time when 99 % of the erythroid cells of the embryo are mature definitive erythrocytes. However, the haemoglobin D /A ratio of lysates from late embryos and young chicks of 0.5 to 20 days of age is consistently greater than that of adult chicken haemoglobin. Definitive erythrocytes of chick embryos and young chicks appear to differ from definitive cells of adult chickens in at least two ways …