Enhancement of Murine Erythopoiesis in Vitro by a Porcine Kidney Extract.

Abstract

We have examined the effect of porcine kidney extract (PKE) on the growth of erythroid progenitor-derived colonies in a methylcellulose culture. The addition of PKE resulted in an enhancement of burst-forming-unit-erythroid (BFU-E)-derived colonies, and the enhancement of the colony was also observed in a low concentration of erythropoietin (Epo) and fetal calf serum (FCS). The activity of PKE on BFU-E was compared with the erythroid growth factors, such as recombinant murine interleukin-3 (IL-3), recombinant murine granulocyte/macrophage colony-stimulating factor (GM-CSF) and recombinant human granulocyte colony-stimulating factor (G-CSF) which are all well known to stimulate BFU-E growth. IL-3 showed a potent burst-promoting activity (BPA), but GM-CSF and G-CSF did not enhance BFU-E growth in our culture conditions. In the cultures supplemented with Epo, the rapid loss of BFU-E was prevented with IL-3; however, PKE alone did not prevent the disappearance of BFU-E. These results suggest that PKE possesses a BPA-like activity which is considered an enhancement of BFU-E.