Final answer:
Leukemia patients and those undergoing stem cell transplants need a bone marrow transplant and thorough compatibility testing. This procedure is preceded by radiation or chemotherapy and includes HLA matching to minimize GVHD and ensure successful engraftment of the new marrow.
Step-by-step explanation:
Patients with leukemia or those undergoing stem cell transplants often require intensive preparatory regimens. For those needing bone marrow transplant, it involves replacing diseased or damaged bone marrow with healthy bone marrow from a donor. Before this can take place, potential family donors must undergo compatibility testing to ensure a match to prevent tissue rejection. If a match is found, the patient will typically receive radiation or chemotherapy to destroy their own diseased marrow before receiving the transplant.
To further minimize the risk of graft-versus-host disease (GVHD), Human Leukocyte Antigen (HLA) matching is performed, and the bone marrow is processed to remove as many Antigen-Presenting Cells (APCs) and T cells as possible, leaving primarily hematopoietic stem cells that will repopulate the recipient's bone marrow and rebuild the immune system.
These protocols are critical, as a successful transplant can cure conditions such as leukemia, by reconstituting healthy blood cell production and immunity in patients.