The single cell origin of normal granulocyte colonies in vitro

Abstract It has been shown by re‐cloning of colonies formed in vitro from rat bone marrow cells, that normal granulocyte colonies can originate from single cells. No mixed macrophage (M) and granulocyte (G) colonies were obtained after re‐cloning either M or G colonies. The results indicate, that clones of normal granulocytes and macrophages can be obtained in vitro , and that the mixed primary M and G colonies formed after seeding hematopoietic cells from animals presumably originate from a mixture of M and G cells.