ScienceDirect, May 2025
A recent study published in Transplant Immunology (2025) reported the successful treatment of an adult patient with very severe aplastic anemia (VSAA) who was positive for donor-specific HLA antibodies (DSA) using double unrelated umbilical cord blood transplantation (dUCBT).
Clinical Background
The patient was diagnosed with VSAA, a condition characterized by a severe impairment of the bone marrow’s hematopoietic function. Prior to transplantation, the patient had detectable DSA, which typically increases the risk of graft rejection and graft failure.
Treatment Method
- Pre-transplant desensitization therapy:
To reduce the levels of DSA and minimize the risk of graft rejection, the patient was treated with:
- Rituximab: a monoclonal anti-CD20 antibody that depletes B cells responsible for antibody production.
- Intravenous Immunoglobulin (IVIG): provides polyclonal antibodies to neutralize DSA.
- Plasma Exchange (PE): directly removes circulating DSA from the bloodstream.
Following this therapy, the DSA levels were significantly decreased, facilitating the transplantation process.
- Double unrelated umbilical cord blood transplantation (dUCBT):
The patient received two units of unrelated umbilical cord blood to ensure an adequate dose of hematopoietic stem cells.
- Conditioning regimen prior to transplantation:
The patient underwent a conditioning protocol consisting of:
- Fludarabine: 30 mg/m² daily for 6 days.
- Cyclophosphamide: 50 mg/kg daily for 4 days.
This regimen aimed to suppress the patient’s immune system, reduce graft rejection risk, and promote engraftment of the cord blood-derived stem cells.
Treatment Outcomes
- The patient achieved complete hematopoietic recovery.
- No signs of graft-versus-host disease (GVHD) were observed.
- The patient maintained stable condition for over one year post-transplant.
Clinical Significance
This study demonstrates that double unrelated umbilical cord blood transplantation combined with desensitization therapy is an effective treatment option for VSAA patients with DSA positivity, especially in the absence of a suitable donor.
References
This article was translated and summarized from the paper:
Lu, M., Leng, J. Y., Xu, C. Y., Lv, C. R., Qian, Z., Zhou, Y., … & Qian, J. (2025). Successful treatment of very severe aplastic anemia with double unrelated umbilical cord blood transplantation in a donor-specific antigen positive adult patient: A case report and review. Transplant Immunology, 102241.
Source: ScienceDirect
Link:https://www.sciencedirect.com/science/article/abs/pii/S0966327425000693?via%3Dihub
