Abstract
Summary
Hemopoietic colony forming cells can be estimated from the assay of CFU, provided the transplantation fraction is known. The fraction for first transplantation cannot be determined by the present methods and has been assumed to be the same as the measurable fraction obtained from a second transplantation. Fractions of CFU recovered on third transplantation were found to be the same as on second, supporting this assumption. Transplantability was altered by treatment of donor mice with irradiation, endotoxin, and VLB. Thus, the loss in CFC between minutes after and 1 day after irradiation was less than the loss in CFU. Pretreatment of irradiated mice with endotoxin or VLB caused a greater reduction in the transplantation fraction than radiation alone. Thus, 1 day after irradiation, differences in CFC values between control and treated mice were even greater than the differences in CFU values previously reported. Clearly, changes in transplantability can be induced and this must be taken into account in the interpretation of effects of various treatments on hemopoietic colony forming cell populations.
Get full access to this article
View all access options for this article.