<qa>  What is a protein made by the body?- Thrombopoietin TPO is a protein made by the body. The bone marrow needs TPO to produce platelets. TPO may also be able to stimulate bone marrow stem cells to produce red cells and white cells. However, TPO cannot be given by mouth. This has led researchers to develop the drug eltrombopag, which acts in the same way and can be given by mouth. Eltrombopag has been shown to safely increase platelet numbers in healthy volunteers and in patients with other chronic blood diseases, including severe aplastic anemia. Researchers are interested in looking at whether eltrombopag can be given to people with moderate aplastic anemia and significantly low blood cell counts. 