Destruction of the host's hematopoietic system is often the result of
allogenic bone marrow transplantation. Mostly used for patients with
chemo-resistant leukemia. Autologous stem cell transplants would likely
return the leukemic cells in the transplanted product.
The recipient is pre-treated with high doses of chemotherapy and/or total
body irradiation. Most successfully recover "a" hematopoietic system.
Sometimes hard to tell whether the cells are host or donor in origin. One
way is in a male-female, donor-recipient pair. Cytogenetics are used to
count XX and XY cells. Dont know if any papers on exact statistics but
I've heard of many cases in which all bllod cells were donor in origin.
However, some degree of donor-recipient chimerism may occur.
There are pros and cons to elimination of the recipient's hematopoietic
system. Hopefully, the leukemia is destroyed and if not, then the new
immune system will kill off the leukemic burden (Graft vs Leukemia effect).
Big danger is if the new immune system recognizes the host as "non-self"
and initiates an immune response (Graft vs Host Disease). This is a very
serious clinical complication. What triggers GVHD in some patients and not
others is unknown. Sometimes the immune response cannot be controlled and
the patient dies due to multi-organ damage.
There is some interesting work underway in a number of centers examining
the apparent tolerance that develops to host/donor tissues in cases were
chimerism develops in the marrow. May have benefits for organ
transplantation.