TPO and autoimmune thrombocytopenic purpura: Of the TPO fluctuations seen in various conditions in which thrombocytopenia occurs, the fluctuations with ITP are reported to differ from those with aplastic anemia or post-chemotherapy bone marrow suppression.[24] That words, in conditions such as aplastic anemia or post-chemotherapy bone marrow suppression where blood TPO rises, TPO is replenished, and the amplification of production signals with the addition of a TPO analog or via TPO receptors is thought to be difficult to obtain.