Bone marrow donation and blood type

Research for a subplot in a novel - not asking for RL medical advice.

Okay - I was going to have a character needing a kidney, but medical advances mean that blood type is no longer so much of an issue there. HLA compatability being more important than a blood type match. Yay for kidney recipients and all that.

Back to the drawing board for the character. It seems that bone marrow donation is still heavily dependant on blood type. So, his kidneys now work, but he has a form of leukemia instead (I know which type - I just don’t have the link on this PC). You may have guessed that Blood type is critical in the plot - you’re clever like that.

Is it still the case that matching blood type is required for marrow transplant?

Why is blood type more important than HLA for this style of donation?

Would pregnancy be enough to disqualify a bone marrow donor?

Transplant seems to be a last resort, how much leeway would a patient have between the need being identified and ‘oops, too late?’

Could a patient in need of a transplant travel - be active (even if only for short periods, say half an hour at a time?)

Thanks very much in advance.

One bump for luck

Having written out the above question, I’m now really intrigued by the HLA vs Blood type question.

Why does HLA ‘trump’ blood type in some donations, but not others?

My understanding was that, at least 10 years ago, blood type was the first indicator of a possible match - if the blood types were different, it wasn’t worth pursuing, because it added another potential complication to an already complicated situation. This is my recollection, based on my friend’s leukemia, and my wanting to see if I could donate, but our blood types didn’t match and we were immediately told not to bother (turned out her brother was a perfect match, so she was lucky… she’s now healthy and working as a nurse in an oncology ward!)

I am curious about the answer to this, and I’ll be watching this thread to see what responses you get.

Well, bone marrow makes blood cells, so that probably has a lot to do with why a blood type match is important.

(IANAD, and all that jazz.)

No, the large teaching hospital I work at has a specific policy regarding ABO Rh mismatch of bone marrow transplantation. In our lab we see this not often, but often enough. With regards to blood transfusion the transplant is divided into three phases.

Phase 1: from the time when the patient/recipient is prepared for bone marrow transplant/hematopoietic stem cell transplantation.

Phase 2: from the initiation of myeloablative therapy until: (for red cell transfusion) the DAT is negative and the anti-donor isohemagglutinin is no longer detectable (ie. if the donor is a group A, no anti-A is detectable); or (for plasma transfusion) the recipient’s erythrocytes are no longer detectable (ie the front typeing is consistant with donor’s ABO type)

Phase 3: front type of the patient is consistant with donor’s ABO type and the back type meets the following criteria <snip, too long to explain>

It’s not necessarily, see above. :slight_smile:

I don’t know the answer, but possibly. Giving birth exposes you to a plethora of forgiegn antignes and a woman will frequently make HLA antibodies in response.


This would be a good question for an actual transplantee. I just came to this thread to squash your hope that ABO matching was super important.

Hvae you considered the thought of autologous stem cell transplantation. I don’t want to get into it, but here’s the wiki break down:

Long time lurker, first time poster here. I’ve had two bone marrow transplants, the latest one in February of this year, so I thought I’d weigh in on this.

My first transplant was autologous, so blood type wasn’t a problem. The second transplant involved an anonymous donor. Type matching was done by some sort of genetic test, not strictly blood type and I was told that it was possible my blood type would change to the donor’s blood type. Ultimately, that wasn’t a factor for me as the donor matched my type.

Oops, too late for what? It can take a while for the donor to be identified. As a white male, it only took about a month to find a match for me, but that’s probably the shortest time possible. About another month for paperwork, testing the donor for any diseases, and setting up a schedule. The actual donation process takes about a week of shots followed by the actual donation. The transplant patient starts their hospital stay at about the same time. I actually had my transplant delayed by several months because the donor was found in late October, and I wanted to wait till the first of the year so I wasn’t in the hospital during Thanksgiving and Christmas.

I was in very good health and active before both my transplants. Now I also had a couple months free of chemo before them as well. During the chemotherapy treatments they used to control my Hodgkin’s, I was varying degrees of sick. Now, once you go into the hospital for the actual transplant, you’re stuck there until your blood counts get high enough for it to be relatively safe for you to leave.

I don’t know if you need to know this but I’ll mention it anyway. Bone marrow donation and transplants no longer involve the painful tapping of the actual bones. Instead, the donor is given a shot each day for 5 to 7 days that boosts bone marrow growth, then the excess stem cells are filtered out of the donor’s blood. Takes two IV’s and a few hours reading a book while your blood cycles through a machine. The transplant process is a week of harsh chemo, a day of rest, and then the bone marrow is just dripped into your blood from a standard IV bag. It takes four to six weeks in the hospital for it to attach and grow enough to sustain you between hospital visits.

In followups, they do genetic tests on your blood to see if it matches the donor’s or your’s.

Probably more then you were wanting, but I hope this answers your questions.

Not at all, that was fantastic. Thank you for contributing that.

Thanks very much, BBS2000 for the medical dope & Goblinboy for delurking (welcome) to share your story.

That was great. Hopeless for the plot of course, but very interesting none the less.

Mnemosyne, that’s what I thought too, but when I saw that the protocol for kidney donation had changed, I reckoned I’d better check. Medicine has outstripped me - this is a great thing for many ill people, so I’m trying not to be bitter about it.

Now I’m going to have to track down all those medical terms and think of a new subplot. Ah well, better that than knowing nothing and alienating the transplanted portion of my potential readership.

The subplot was that the (adult) daughter was being pressured into a donation - which ultimately (big twist!) she was unable to give because of incompatibility, having the other parent’s blood type. I’ll just have to find something else the parent wants/needs that a very eager to please person would eventually be unable to do (absolving her of responsibility - that’s important because this character has issues in that area).

Thanks again. Very much appreciated.

Dug some interesting reads for you guys.

Ask the bone marrow courier

Ask the (soon-to-be) Bone Marrow Doner.

Ask a transplant recipient
And yes, this is a gentle nudge of a suggestion that** Goblinboy ** starts his own “Ask the…” thread.


I’m already a blood donor and will be an organ donor when I kick off (though I pity the fool who gets my misshapen corneas!) I’ll ask about the marrow donation next time I’m havin a pint taken.

Those are some nice links bigbabysweets2000, thank you for digging them up. I asked the doctors plenty of questions about the donor, but never even considered the courier.

As for starting an ‘Ask the…’ thread, I’ll think about it.