Therapies for Leukemia Patients Essay -- Leukemia

Executive Summary Two promising therapies for leukemia patients are bone marrow transplantation and peripheral stem cell transplantation. Successful transplants require that two immunologic barriers be overcome: a host-versus-graft (HVG) reaction and a graft-versus-host (GVH) reaction. A myeloablative conditioning regimen, which involves a depletion of the patient’s immune system, usually precedes the transplantation of donor stem cells to control the HVG. However, twentyfive to 35% of patients undergoing bone marrow transplantation experience life-threatening transplant-related complications (Holler 1990). Serum tumor necrosis factor (TNF)-_ levels are elevated prior to these complications and are indicative of future problems, such as rejection, graft-versus-host disease, interstitial pneumonitis, endothelial leakage syndrome, and venoocclusive disease (Remberger 1994). As a result, many patients who are at high risk for these complications, including patients over 55 years old, patients with poor overall health, and children, are turned down for stem cell transplantation. In the mid-1990’s, a regimen was developed that uses non-myeloablative conditioning. In this procedure, the immune system of the recipient is not totally depleted, which creates a tolerable regimen for those high risk patients. This project will compare the relative toxicity of myeloablative allogenic peripheral blood stem cell transplantation (PBSCT) and non-myeloablative PBSCT. This will involve collecting patient serum samples at various time intervals during treatment. The samples will be evaluated for TNF-a concentrations using the ELISA technique. The data will then be used to determine the toxicity of each regimen. This study will p... ...ne response. MacKay I, Rosen F: The Immune System. NEW ENGLAND JOURNAL OF MEDICINE 2000; 343: 108-117. This is the second part of the review article on immunology. It describes lymphocytes and lymphoid tissue, molecular aspects of the immune response, the activation and regulation of lymphocytes, immune protection by antibodies and immunologic technology. Tanaka J, Imamura M, Kasai M, et al: The important balance between cytokines derived from type 1 and type 2 helper T cells in the control of graft-versus-host disease. BONE MARROW TRANSPLANTATION 1997; 19: 571-576. This article assesses the cytokine network after transplantation, and its connection to graft-versus-host disease (GVHD). It looks at the balance between type 1 (Th1) and type 2 (Th2) helper T cells, and concludes that severe GVHD may be related to a cytokine imbalance between the helper cells.