Differential effects of microenvironmentally presented interleukin 3 versus soluble growth factor on primitive human hematopoietic cells.
AUTOR(ES)
Otsuka, T
RESUMO
The effect of IL-3 on hematopoiesis in long-term culture (LTC) was studied by cocultivating normal human marrow cells with human marrow fibroblast feeders engineered to constitutively produce IL-3 and by adding soluble IL-3 to LTC according to a variety of dose-time schedules. Feeders stably producing 7 ng/ml IL-3, or LTC to which 10 ng/ml IL-3 was added daily for 5 wk, but not once or twice weekly for the same time period, increased the output of mature nonadherent cells and progenitors from LTC as compared to control cultures. At the time of the weekly half-medium change, when primitive clonogenic progenitors in the adherent layer of standard LTC are quiescent, such cells were actively cycling in cultures containing a continuous source of an adequate dose of IL-3. In LTC, where the proportion of IL-3-producing cells in the feeder layer was diluted to 10% and no IL-3 was detectable in culture medium, primitive adherent layer progenitors were, nevertheless, maintained as a population of continuously proliferating cells. Thus, the presence of IL-3 in LTC can enhance the proliferation and differentiation of very early human hematopoietic cells, but the concentration, duration of exposure, and method of IL-3 presentation are important determinants of the ultimate effects observed.
ACESSO AO ARTIGO
http://www.pubmedcentral.nih.gov/articlerender.fcgi?artid=295347Documentos Relacionados
- Differential effects of interleukin-2 and interleukin-4 on immunomodulatory role of platelet-activating factor in human B cells.
- Interleukin 3 or interleukin 1 abrogates the reconstituting ability of hematopoietic stem cells.
- Human interleukin 7: molecular cloning and growth factor activity on human and murine B-lineage cells.
- Production of interleukin 1beta by human hematopoietic progenitor cells.
- Differential expression of the amv gene in human hematopoietic cells.