Who Can Be a Donor for BMT?
Donor for BMT has to be matched with the patient in their ‘tissue type’. This is confirmed by typing their HLA antigens.
Fully HLA Matched
Within a family, there is about 25-30% chance of finding such a match in a brother or a sister. If there is no match within the close family, the chances of finding a fully HLA matched donor in distant relatives is remote.
We inherit two sets of HLA ANTIGENS; one from each parent Thus, parents are always half matched with us. In addition, even if the brothers and sisters are not fully matched with the patient, there is 90% chance that they shall be half-matched. BMT from a half matched or HAPLOIDENTICAL donor is feasible in centres with adequate infrastructure and expertise. Dharamshila Hospital and Research Centre is the only hospital of India to have created the desired infrastructure and has the expertise for this procedure.
Volunteer Unrelated Donors
To find a match with a random person is less than one in a billion. However, if we screen million people of similar ethnic background, we might find a close match. Based on this concept, volunteer unrelated donor registries have been set up in all developed countries and they are the major source of blood stem cells in all these countries. Several such registries worldwide provide over a million donors who volunteer to donate marrow if needed. The best chances of finding a match are within the same ethnic community. Unfortunately, no such registry exists in India at present.
What is the process of donating bone marrow, does the donor face any health problem due to donating bone marrow?
Hundred milliliter to a litre of bone marrow (depending on the age of the patient and the donor) is withdrawn under general anaesthesia from donor’s hipbone. If the donation of more than 500 ml of bone marrow is anticipated, one unit of blood is collected from the donor and stored. This stored blood is transfused back to the donor during or after he has donated the bone marrow.
Does the donor face any health problem due to donating peripheral blood stem cell?
No. The donor receives an injection of a growth-factor for 4 days and on the fifth day the donation takes place. Similar to collection of blood, the donor's vein is punctured with a needle whose tubings are connected to the machine called cell separator. The donor can sit on a motorized couch and relax, while the procedure goes on. This usually takes 3-4 hours. The platelet counts might drop a little after the procedure, but this returns to normal in 2-3 days. Over 10,000 donations of peripheral blood stem cell has been collected without any harm caused to the donor.