A Semi-Bone Marrow Transplant

~And other effective advancements in Transplants for SCD~
Author: Kara Martina B. Sc. Biopsychology 

A Semi bone marrow transplant relies on a half-matched sibling to donate unaffected tissue. In the past, BMTs have been heavily and almost solely dependent on close HLA matches. In the States, finding an unrelated match can cost over 50 000 USD and sometimes the chance of finding said donor runs only 30%.

A semi bone marrow transplant sidesteps the restrictive nature of a typical BMT, using partially matched marrow followed by immediate chemotherapy to combat the rejection response. This semi-compatible approach has opened effective treatment for over 95% of children related to a half-match (1).  The outcomes have been surprisingly favorable and given the actual limited resources that most people live with, this creative method may be the saving procedure for many with TM, SCD and leukemia (2).  

In related findings, researchers have discovered that semi-mature and ‘silenced’ bone marrow cells induce tolerance rather than an undesirable immune response (3). The long foe of BMT, Graft Versus Host Disease (GVHD) can kill patents even after a successful procedure. Using semi-mature cells, with a muted 88 factor allowed rats in the experiment to withstand even fully mismatched grafts.  

Another study found that administering donor B-cells immediately following a semi-allegoric transplant prolonged GVHD (4). Usually following a transplant, IV immunoglobulins are readily administered, including T-cells. This study administered only donor B-cells on grafted mice.  T-cell depleted mice injected with only donor B-cells never developed GVHD, whereas mice with T-cells died of organ rejection.

Still in the making and forever perfecting, Bone marrow transplants and Semi-bone marrow transplants need further research and a more developed protocol following and preceding procedure. Graft Versus Host disease risks along with the effects of chemotherapy before transplants are both as formidable as the original disease BMTs aim to cure, be it leukemia, thalassemias or Sickle Cell Disease.    

When will all the research we fund make a difference? When will the safest and best procedures and protocols develop such that those with blood disorders are not threatened by the very treatments meant to save their lives?

See more on hazardous effects of chemotherapy drugs here. 
See more on specific chemo mechanisms here.
What can you do? Be aware, ask your doctor these 20 questions! Don’t just blindly accept or rely on a prescribed chemotherapy. 

References

1. Luznik, L., Engstrom, L. W., Iannone, R. & Fuchs, E. J. Posttransplantation cyclophosphamide facilitates engraftment of major histocompatibility complex-identical allogeneic marrow in mice conditioned with low-dose total body irradiation. Biol. Blood Marrow Transplant. J. Am. Soc. Blood Marrow Transplant. 8, 131–138 (2002). - See more at: http://www.cure2children.org/content/making-cure-possible-even-more-children-using-mother%E2%80%99s-bone-marrow-save-her-child#sthash.ulQXkdVz.dpuf

2. Bolaños-Meade, J. et al. HLA-haploidentical bone marrow transplantation with post-transplant cyclophosphamide expands the donor pool for patients with sickle cell disease. Blood (2012). doi:10.1182/blood-2012-07-438408 - See more at: http://www.cure2children.org/content/making-cure-possible-even-more-children-using-mother%E2%80%99s-bone-marrow-save-her-child#sthash.ulQXkdVz.dpuf

3. Yang, XJ., Meng, S., Zhu CF., Jiang H. &Wu WX. Semi-mature MyD88-silenced bone marrow dendritic cells prolong the allograft survival in a rat model of intestinal transplantation. Chin Med J (Engl). 2011 Jan;124(2):268-72.   4. Samuel, S., Azar, Y., Corchia, N. & Or R. Improved immune function with donor B-cell infusion after semi-allogeneic bone marrow transplantation in mice. Arch Med Res. 2008 Jan;39(1):61-8. 

4. Samuel, S., Azar, Y., Corchia, N. & Or R. Improved immune function with donor B-cell infusion after semi-allogeneic bone marrow transplantation in mice. Arch Med Res. 2008 Jan;39(1):61-8.