DP Antibody in Heart Tx

Mon, 28 Nov 2016 17:18:18 GMT

All-

I have a patient on our heart waiting list that was on ECMO and has an RVAD and LAVD implanted. He is very highly sensitized with a Bw4 antibody, additional B unacceptables, DR, DQ and DP antibodies. Our big concern is with his DP antibodies. He is DPB1*04:01 homozygous with antibodies >10,000 to almost all other DP antigens. We have done several surrogate crossmatches and they have all been B cell positivewith anyone that is not 04:01 homozygous.

Does anyone have experience performing heart transplants across DP positive crossmatches? Did the patients have any issues post transplant? I know some have done kidney transplants with some success, but I have not seen any data about hearts.

Thanks!

Wed, 30 Nov 2016 00:00:55 GMT

Does this person even have a positive flow crossmatch against DPB1*04:02? They have such shared epitopes that i wonder if that XM would be positive, or at least the most permissive way to open up the donor pool.

Tue, 6 Dec 2016 20:26:43 GMT

They have antibody against 04:02 by SAB. I have no idea on a real XM. We had one donor in the lab that was antibody negative for everything except DP (donor was A, recip was O) so I tried the XM to see what would happen (donor was DP03:01, 15:01). The XM was positive at about a 200 channel shift on the B cell FXM.