Removes antibodies. Plasma exchange or plasmapheresis is designed to remove antibodies (proteins) from the plasma fraction of the blood, which is then replaced with other plasma or albumin. It is done when the recipient has antibodies targeting the hla antigens in the donor. It may be done before or after the transplant; and is useful to prevent or treat rejections.
ABO INCOMPATIBLE. Most plasma exchanges or plasmapheresis are done to be able to transplant people across the ABO group or in cases of extreme sensitization to other antigens. Results are variable, and depends on the desensitization protocol.
Not very harmful. If someone spoke to you about plasma exchange, then the issue is the presence of anti-donor antibodies in the recipient. The procedure removes the plasma containing the antibodies. The procedure is used either at the time (or just before) the transplant to prevent rejection in sensitized patients. Or, after the transplant if antibody mediated rejection has occurred.