Thiamphenicol as an inhibitor of early red cell differentiation.

The effects of an in vivo treatment of mice with thiamphenicol on stem cells are shown. Thiamphenicol causes a drastic depletion of erythroid precursors in the marrow. Mitochondrial protein synthesis is inhibited resulting in a severely reduced cell proliferation. The number of pluripotent stem cells in the marrow did not decrease. In the spleens of thiamphenicol-treated mice a strong reduction of stem cells was found. The sedimentation behaviour of stem cells from anemic and thiamphenicol-treated mice was similar. The pluripotent stem cells from thiamphenicol-treated mice were in a low cycling state, despite a very high erythropoietin level. Under these circumstances a partial commitment of the pluripotent stem cells into the erythroid direction was observed.