Unexpected unrelated umbilical cord blood stem cell engraft in two patients with severe aplastic anemia that received immunosuppressive treatment: A case report and literature review

Abstract

Abstract. Severe aplastic anemia (SAA) is a life-threatening bone marrow disorder. Bone marrow transplantation is the primary therapy for SAA; however, its efficacy is limited by numerous factors, including lack of histocompatible sibling donor, patient age and graft-versus-host-disease (GVHD) following transplantation. Immunosuppressive treatment (IST) is the first procedure developed for patients without a sibling donor. Our previous study reported that patients administered enhanced IST, in addition to a regime of unrelated umbilical cord blood (UCB) transfusion, exhibited higher efficiency and a reduced rate of relapse. Therefore, the present study reported the cases of 2 patients that received enhanced IST plus unrelated UCB transfusion. These patients exhibited complete hematological recovery with an increased rate of mixed chimerism and demonstrated no signs of GVHD or relapse during the 2-year follow-up period. Thus, enhanced immunosuppressive treatment (low-dose cyclophosphamide and antithymocyte globulin) combined with UCB transfusion may be an effective treatment for patients with SAA.

Population Pharmacokinetics of Tacrolimus in Pediatric Patients With Umbilical Cord Blood Transplant

“…To the best of our knowledge, this was the first PPK analysis of tacrolimus in pediatric patients with UCBT. Posttransplant early immune disorders were major issues in UCBT 30 . Tacrolimus was commonly used in the prevention of aGVHD in UCBT pediatrics.…”

“…Posttransplant early immune disorders were major issues in UCBT. 30 Tacrolimus was commonly used in the prevention of aGVHD in UCBT pediatrics. However, it was difficult to administer, especially in pediatric patients.…”

Child with Wiskott–Aldrich syndrome underwent atypical immune reconstruction after umbilical cord blood transplantation: a case report

“…UCBT has many advantages for treating WAS, as compared to other types of HSCT. For example, the acquisition of CB is easy, collection of CB is harmless, and the CB handling process, such as thawing, does not induce loss of cell proliferation[4,13-16]. In addition, CB transplantation showed a lower risk of acute and chronic GVHD than other transplantation strategies using a different cell source[17,18].…”

“…In general, innate immunity, namely phagocytes and natural killer lymphocytes, recovers in the first few weeks after transplantation. Then, the adaptive immune system, namely B and T lymphocytes, recovers, which may take months to years[7,9,16,20]. Reconstitution of CD4 + T cells is later than that of CD8 + T cells, which in most cases also results in a long period of CD4 + /CD8 + inversion after transplantation.…”