My aunt needs blood urgently, but she happens to be 0- and neither the hospital nor family and friends are able provide this blood type to her. However, I was wondering if it makes sense to take only the compatible components from each person. I myself am 0+ so there should be no issue fro the antibodies. And we do have a couple of negative blood types in the family (just not 0-). Normally the doctors will be the ones to decide, but I'd like to ask if it is not 100% stupid as an idea.

1 Answer 1


There are no stupid ideas, this is a very good question. Unfortunately the answer is you can't do this - what determines the blood type is the presence of antigens on the surface of red blood cells. Simply put, antigens can trigger certain responses from the immune system. Here are the four types:

Type A: Only the A antigen on red cells (B antibody in the plasma). The second most common blood type.

Type B: Only the B antigen on red cells (and A antibody in the plasma).

Type AB: Both A and B antigens on red cells (both A and B antibody in the plasma).

Type O: Neither A nor B antigens on red cells (both A and B antibody in the plasma). The most common blood type.

In addition to the A and B antigens, there is a third antigen called the Rh factor, which can be either present (+) or absent ( – ). In general, Rh negative blood is given to Rh-negative patients, and both Rh positive blood or Rh negative blood may be given to Rh positive patients.

It is possible to give o+ blood to an o- patient, but it carries certain risks, and is only done in very desperate situations and when the patient is beyond a certain age. If incompatible blood is given in a transfusion, the donor cells are treated as if they were foreign invaders, and the patient's immune system attacks them, which can be catastrophic. So the blood type is dependent on what's on the surface of the red blood cell, not some component that can be manipulated.

I hope this clears things up and hope your aunt gets better!

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