Successful transplantation of HLA-matched and HLA-mismatched umbilical cord blood from unrelated donors: analysis of engraftment and acute graft-versus-host disease. Analysis of the alloreactive capacity of human umbilical cord blood: implications for graft-versus-host disease. Laughlin has been performing umbilical cord blood transplants in adults, who are at an increased risk of developing graft-versus-host disease.