ABSTRACT
A method described by Harrison has been adopted and modified by us for the separation of intermediate and late erythroblast cells from 15 day embryonic liver of pregnant Wistar rat. The method consisted briefly of preparation of fetal liver cell suspension and the separation of cell types in a 40% and 70% nonlinear Percoll gradient system. Using this method, we can obtain about 96% of hemogenous population of intact and viable intermediate and late erythroblasts. Examination of tho separated cells by Giemsa and benzidine staining and by electron microscopic observation indicated that no granulocytes or other white blood cells could be detected, except for some contamination of about 1% of proerythroblasts and 3% of reticulocytes in the fraction. Trypan blue vital staining demonstrated that there were over 95％ of the cells maintained viable after separation, they could be used directly for the study of cell differentiation as well as biochemical analysis. SO, this is an economical, simple and easy technique to operate which proved to be a useful mean for obtaining enrich population of intermediate and late erythroblasts in research in the field of cell biology.
ABSTRACT
The present study reported the observations with light and electronic micros copy on hybrid cells crossed between rat intermediate or late erythroblasts and mouse SP2/0 plasmocytoma cells. In a short period after fusion, the cell size and the ratio of nuclear heterochromatin in hybrid cells appeared to be increased, but the number of nucleoli, as well as the number of microvilli, finger-like processes, and nuclear cytoplasmic ratio were decreased. Swelling mitochondria, pycnotic nuclei and/or process of enucleation also could be seen in some hybrid cells. The subcul tured hybrid cells were characterized with less microvilli and cellular surface membrane processes, and showing marked changes in nuclear size, as well as the appearance of cytoplasmic vesicles and dense granules in some cells. The observations mentioned above provide morphological and ultrastructural evidences for the regulation of malignant phenotype of hybrid cell model we reported previously. The possible relationship between the deeancerization and the morphological changes of hybrid cell nucleus, cytoplasm and cell surface were briefly discussed.