Transplants of Hematopoietic Stem Cells

Hematopoietic stem cells (HSCs) are the cells from which all the types of blood cells are made. [Discussion]

They reside in the bone marrow and can be harvested from it. However, a few infusions of granulocyte colony-stimulating factor (G-CSF) — available thanks to recombinant DNA technology — causes them to be released into the blood where they can more easily be collected.

They are used to treat a variety of ailments including In 2006, some 50,000 of these transplants were performed worldwide.

High doses of chemotherapy and radiation can be used to kill off the cancerous cells in a patient, but they also destroy the patient's bone marrow, and the patient will die without a transplant of hematopoietic stem cells.

These can be:

In one remarkable case, an AIDS patient with leukemia was given a bone marrow transplant from a donor whose cells did not express a functional version of CCR5 — a coreceptor needed by HIV to infect T cells [More]. Two years later, the patient was not only cured of his leukemia but of AIDS as well.
If the patient's own marrow was not completely destroyed, the donor lymphocytes and the patient's lymphocytes can exist together. Then a later infusion of the donor's T cells may be able to kill off all the patient's remaining malignant cells leaving the patient with a bone marrow that produces donor-type cells exclusively. [Link to further discussion]

So hematopoietic stem cell transplants (HSCT) can be life-saving but create their own problems. (Another example: an "immediate"-type allergy like hay fever or asthma of the donor can create the same allergy in the recipient.)

Autologous hematopoietic stem cell transplants also show promise of being an effective treatment for the autoimmune disorder systemic lupus erythematosus (SLE)
Link to a discussion of other types of organ transplants
Welcome&Next Search

20 October 2012