Buy Cellcept 500mg Online can be used alone or with other medications to keep your body from attacking or rejecting an organ transplant. It is used for kidney, heart and liver transplants. Cellcept suppresses the immune system so that it cannot attack the newly transplanted organs. This can also cause you to be more susceptible to infection, so you should try to avoid infection while on this medication. Below you will find the uses of Cellcept.