ISSN:
0021-9541
Keywords:
Life and Medical Sciences
;
Cell & Developmental Biology
Source:
Wiley InterScience Backfile Collection 1832-2000
Topics:
Biology
,
Medicine
Notes:
The course of the differentiation and proliferation of the human erythroid burst-forming units (BFU-E) to colony-forming units (CFU-E) was directly investigated using a combination of highly purified BFU-E, a liquid culture system, and the following clonal assay. Highly purified human blood BFU-E with a purity of 45-79% were cultured in liquid medium with recombinant human erythropoietin (rEP) and recombinant human interleukin-3 (rlL-3) to generate more differentiated erythroid progenitors. The cultured cells were collected daily for investigating the morphology, the increment in the number of cells and the clonality. Ninety percent of purified BFU-E required not only rEP but also rlL-3 for clonal development. By 7 days of liquid culture, the total cell number increased 237 ± 20-fold above the starting cells, while erythroid progenitors increased 156 ± 74-fold. As the incubation time in liquid culture increased, the cells continuously differentiated in morphology. Replating experiments with rTEP combined with or without rlL-3 showed the following: (1) The number of erythroblasts that were part of erythroid colonies decreased with accompanying erythroid progenitor differentiation and proliferation. (2) As the incubation time in liquid culture increased, erythroid progenitors had a graded loss of their dependency on rlL-3 and a complete loss of dependency was observed after 3 days of liquid culture. At that time 85% of the erythroid progenitors gave rise to colonies of more than 100 erythroblasts which were equivalent to mature BFU-E. These studies provide a quantitative assessment of the loss of lL-3 dependency by BFU-E and indicate that the size of the generated erythroid colonies and their lL-3 requirement correlate with the erythroid differentiated state.
Additional Material:
5 Ill.
Type of Medium:
Electronic Resource
URL:
http://dx.doi.org/10.1002/jcp.1041490102
