Quantitative Response of Bone Marrow Colony-Forming Units (CFU-C and PFU-C) in Weanling Beagles Exposed to Acute Whole-Body γ Irradiation

• Published in: Radiation research 1978-05, Vol.74 (2), p.289-297
• Main Authors: Wilson, F. D., Stitzel, K. A., Klein, A. K., Shifrine, M., Graham, R., Jones, M., Bradley, E., Rosenblatt, L. S.
• Format: Article
• Language: English
• Subjects: Animals; Bone marrow; Bone marrow cells; Bones; Cell Survival - radiation effects; Dogs; Dose-Response Relationship, Radiation; Gamma Rays; Hematopoietic stem cells; Hematopoietic Stem Cells - radiation effects; Irradiation; Progenitor cells; Radiation tolerance; Spleen cells; Stem cells; Weanlings
• ISSN: 0033-7587; 1938-5404
• DOI: 10.2307/3574889

Using a methylcellulose-supported bone marrow culture system, the dose-response relationships of suspended granulocyte-monocyte colonies (CFU-C) and adherent fibroblastic colonies (PFU-C) were investigated in 2- to 3-month-old beagles exposed to acute whole-body γ irradiation. Groups of weanling beagles were exposed at a rate of 140 R/hr delivered from a60Co γ source achieving total exposures ranging from 0 to 586 R. Twenty-four hours following irradiation, bone marrow was collected, plated into methylcellulose, and after 1 week of incubation both colony types were quantitated. In addition, bone marrow cellularity determinations were made for a variety of bones using an^{59}{\rm Fe}\text{-labeling}$technique. The results show a${\rm D}_{37}$for the linear part of the slope of 70 R for CFU-C. Although within the limits of the experiment a${\rm D}_{37}$could not be established for the fibroblastic populations, the results indicate a substantial degree of radioresistance for these elements supporting our previous studies on PFU-C, performed on mice, which suggested a${\rm D}_{37}$of ∼400 R for the progenitors of these fibroblastic elements.