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Slow platelet recovery after PBPC transplantation from unrelated donors
J Jansen1, S G Hanks, L P Akard
1Stem Cell Lab, Indiana Blood and Marrow Transplantation and St Francis Hospital and Health Centers, Beech Grove, IN 46107, USA. jjansen@ibmtindy.com
Abstract:
The effects of the composition of PBPC grafts from matched related donors (MRDs) and matched unrelated donors (MUDs) have not been compared. In a single-center study, the compositions of 55 MRD PBPC grafts and 33 MUD grafts were studied for their effect on the rate of engraftment in patients who had evidence of donor cell engraftment on day +28. The MUD grafts came more frequently from young male donors and contained more CD34(+) cells but similar numbers of colony-forming units granulocyte-macrophage (CFU-GM) and burst forming units-erythroid. The recovery of neutrophils to >500/mm(3) was equally fast in both groups, but recovery of platelets to >20,000/mm(3) was significantly delayed in the MUD group (P<0.001). The MUD group also required more transfusions of platelets and red cells. Patients receiving grafts containing low numbers of CFU-GM had markedly delayed platelet recovery. The patients with the slowest engraftment tended to have prolonged transportation times. Storage experiments suggested a major loss of viable CD34(+) cells and CFU-GM when undiluted PBPC products are stored at room temperature. The data suggest that a fraction of the MUD grafts suffer during transportation. In vitro proliferation assays should be part of the validation and auditing of transportation of MUD grafts.
Insights
Peripheral blood progenitor cell (PBPC) grafts from matched unrelated donors (MUDs) showed delayed platelet recovery compared to matched related donors (MRDs). Transportation time and storage conditions significantly impact MUD graft quality and patient engraftment outcomes.
Area of Science:
- Hematology
- Transplantation Immunology
- Cellular Therapy
Background:
- Graft composition differences between matched related donors (MRDs) and matched unrelated donors (MUDs) for peripheral blood progenitor cell (PBPC) transplantation are not well understood.
- Understanding these differences is crucial for optimizing engraftment and patient outcomes.
Purpose of the Study:
- To compare the composition of MRD and MUD PBPC grafts.
- To evaluate the impact of graft composition on engraftment kinetics, specifically neutrophil and platelet recovery.
- To identify factors influencing graft quality during transportation and storage.
Main Methods:
- Single-center study analyzing 55 MRD and 33 MUD PBPC grafts.
- Assessment of graft composition, including CD34(+) cell counts and colony-forming units (CFU-GM).
- Monitoring of neutrophil and platelet engraftment timelines and transfusion requirements.
Main Results:
- MUD grafts, often from younger male donors, had higher CD34(+) cell counts but similar CFU-GM and burst forming units-erythroid compared to MRD grafts.
- Neutrophil recovery was comparable, but platelet recovery was significantly delayed in the MUD group.
- Lower CFU-GM counts correlated with delayed platelet recovery, and prolonged transportation times were associated with slower engraftment.
Conclusions:
- PBPC grafts from MUDs can lead to delayed platelet recovery, potentially due to graft quality issues during transportation.
- Storage conditions, particularly at room temperature, can degrade viable CD34(+) cells and CFU-GM.
- In vitro proliferation assays are recommended for validating and auditing MUD graft transportation processes.
