PLURIPOTENT AND COMMITTED HEMATOPOIETIC PROGENITOR CELLS IN RAT PERIPHERAL-BLOOD

The assay system for determination of haemopoietic progenitors in peri pheral blood of rats is essential for potential studies on mobilisatio n and transplantation of circulating progenitor cells in a rat experim ental model. This paper demonstrates the possibility of detection and quantification of pluripotent progenitors (Colony Forming Units-Spleen day 8-CFU-Sd8) and committed progenitors (Colony Forming Units Granul ocyte Macrophage-CFU-GM and Burst Forming Units-Erythroid-BFU-E) in pe ripheral blood of rats in a steady state. For determination of CFU-Sd8 the 'rat to mouse' in vive assay was used, and for committed progenit ors in vitro assays on methylcellulose were employed. The CFU-Sdg inci dence ranged from 7.3 to 11.6/ml of rat blood, similar to that reporte d in literature for mice. The incidence of CFU-GM was found to be 59.7 +/- 9.4/ml which is in the range of the literature data for mice, rab bits, dogs and humans. The incidence of BFU-E in rat peripheral blood was 4.3 +/- 1/ml, which was relatively low, but could be also consider ed as comparable with some literature data for dogs and humans. The CF U-E were not detected by the technique used. These results confirmed t he existence of circulatory blood pluripotent progenitors (CFU-Sd8) an d committed (CFU-GM and BFU-E) progenitors in rat, as has been establi shed for some other mammalian species.