This study is part of our research program seeking to develop new, potentially curative treatments for autoimmune diseases and understand the regeneration of organs that occurs after autoimmunity is removed. . In this process we discovered a splenic stem cell with the unique human and murine adult expression of the Hox11 protein, a well-known oncogene that was originally described by Dr. Stan Korsmeyer. But unlike traditional opinion of this protein as an oncogene we discovered Hox11 identifies a very early fetal cell with multi-lineage potential to regenerate even in adult mice. In both the mouse and human this stem cell in non-diseased animals sits exclusively in the spleen. To date Hox11 stem cells have been shown to regenerate insulin-secreting islets, parts of the inner ear, salivary glands, tongue and bone tissues. Also additional work for our lab has suggested that splenectomy might be a new treatment option for ALL human tumors and a means to test the stem cell hypothesis by perhaps removing the origins of the cancer stem cell in an unusual location i.e. the spleen not the bone marrow of adults.