Negative and Positive Feedback Control of the Committed Granulocytic Stem Cell Compartment,
Abstract
Although there exists some evidence that proliferation and differentiation of the multipotential stem cell (CFU-s) is at least partly controlled by cell-to-cell interaction, it appears that the committed granulocytic colony forming cell (CFU-c) is under the influence of stimulatory or inhibitory humoral agents. The latter is supported by the fact that the addition of material containing colony stimulating activities (CSA) to the semisolid medium of in vitro bone marrow cultures permits the formation of granulocyte and macrophage colonies. CSA has to date only been partially purified and appears to be a glycoprotein with a molecular weight of 45,000 daltons. At present there exists no final proof that CSA stimulates granulopoiesis in vivo, however, indirect results from several studies appear to make it a good candidate. Along these lines our studies utilizing either (1) the diffusion chamber methodology and cytoxan treatment of mice or (2) murine models of inflammatory exudates support the hypothesis that CSA represent long distance humoral agents possibly produced by mononuclear cells that migrated into inflammatory exudates.
Document Details
- Document Type
- Technical Report
- Publication Date
- Jan 01, 1977
- Accession Number
- ADA054065
Entities
People
- Siegmund J. Baum
Organizations
- Armed Forces Radiobiology Research Institute