Bone Marrow Transplantation: Autologous and Allogeneic
Hematopoietic stem cell transplantation (HSCT) is the new name for bone marrow transplantation.
The bone marrow is home to hematopoietic stem cells (HSCs), also called pluripotent stem cells because they can give rise to any cell your body requires at any given moment. These specialized cells play an essential role in replenishing our blood supply on a daily basis to maintain blood counts in a healthy host. These cells can be ”collected” either by performing repeated bone marrow aspirations or by “mobilizing” HSCs into the circulation using special medications called cytokines (like GCSF, also called neupogen), and filtering them out of your blood using a highly specialized process called apheresis. After they are collected from your body, these stem cells can be preserved by storing them in a chemical called DMSO, and placing them in a freezer. Stem cell transplantation refers to a process whereby the patient’s HSCs are replaced by new cells (either from yourself [autologous] or someone else [allogeneic] that grow into a healthy hematopoietic system.
There are many types of HSCTs depending on the source of stem cells as described below:
Autologous Stem Cell Transplantation:
Autologous stem cell transplants are predicated on a simple concept: if a little chemotherapy has the potential to cure, than a lot could be even better. For lymphoma that has come back after conventional chemotherapy, this disease is not usually sensitive to lower doses of chemotherapy, so there is a need to consider higher doses. The challenge of course, is that higher doses of chemotherapy, while effective at treating the lymphoma, can also destroy all your body’s normal blood cells. Hence, after receiving high dose chemotherapy, there is a need to re-infuse your own normal stem cells, collected before you get the high dose therapy.