This trial is designed to evaluate the safety of treating systemic lupus erythematosus participants with cyclophosphamide and CAMPATH-1H followed by allogeneic stem cell transplant. There will be no randomization in this study. All subjects who are determined to be eligible for the study treatment will receive cyclophosphamide and CAMPATH-1H followed by allogeneic stem cell transplant. The purpose of the intense chemotherapy is to destroy the cells in the immune system which may be causing this disease. The purpose of the stem cell infusion is to produce a normal immune system that will no longer attack body. The study purpose is to examine whether this treatment will result in improvement in the lupus disease.