---------- > From: rbigler@concentric.net > To: tfarley@computer.net > Subject: Re: CD34 cells separation > Date: Wednesday, August 27, 1997 5:22 PM > > Has any host had their stems cells eliminated and then their > total production of blood cells converted > from male to female or visa versa by means of a pleuripotent > stem cell transplantation? If that can be done, a > transplanted organ from the stem cell donor should work > without immunosuppression. > > What do you think about the in in vivo use of a short-range > radionuclide labeled mAb to CD34 for the purpose of total > elimination of the host stem cell population? 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.
This archive was generated by hypermail 2b29 : Wed Apr 03 2002 - 11:50:04 EST