<qa>  What is the name of the drug that is given to protect the bladder from the CyclophoIf G-CSF does not stimulate the stem cells sufficiently, the patient will receive a single dose of drug called cyclophosphamide chemotherapy intravenously into a vein. This drug will cause the blood cell counts to fall. A drug called MESNA will also be given to help protect the bladder from the Cyclophosphamide. After completing chemotherapy, patients will be started on G-CSF again until blood cell counts reach a certain level, at which time the patient will undergo leukopheresis. Leukopheresis is a procedure where blood is removed from one arm, pumped into a machine where the white blood cells are separated from most of the other cells and then returned through the same needle or through a needle in the other arm. This procedure usually takes 3 to 4 hours a day for up to 4 days in a row, depending on how many cells are collected each time. 