Effect of double dose plateletpheresis on target yield and donor platelet recovery

Abstract Introduction The demand for apheresis platelets has increased in the recent past and the shrinking donor pool has shifted the trend to collection of double-dose or higher yield of platelets. Objective The present study aimed to determine the effect of double-dose plateletpheresis on the target yield and donor platelet recovery. Methods The study was conducted on 100 healthy plateletpheresis donors, 50 of whom were in the study group, which underwent double-dose plateletpheresis (DDP), and 50 of whom were in the control group for single-donor plateletpheresis. Pre- and post-procedure samples of donors were subjected to a complete blood count. The DDP product was sampled for platelet yield and then split into two parts. Platelet yield, collection efficiency, collection rate, recruitment factor and donor platelet loss were calculated. Results The mean platelet yield in the SDP was 4.09 ± 1.15 × 1011 and in the DDP, 5.93 ± 1.04 × 1011. There was a significant correlation between the pre-donation platelet count and platelet yield. The total of platelets processed for the SDP were 5.42 ± 1.08 × 1011 and for the DDP, 7.94 ± 0.77 × 1011. The collection efficiency was 71.93 ± 25.14% in the SDP and 72.94 ± 16.28% in the DDP, while the collection rates were 0.78 × 1011 and 0.94 × 1011 per minute, respectively. The average recruitment factor observed was 0.98 in the SDP, while it was 0.99 in the DDP. The mean platelet loss observed in the SDP was 35.55 ± 8.53% and in the DDP, 37.76 ± 8.65%. Conclusion The double-dose plateletpheresis supplements the platelet inventory in developing countries where the apheresis donor pool is limited. It is prudent to ensure stringent donor selection criteria for donors donating high-yield platelet products, thus enhancing donor safety and retention.

Effects of Human Platelet Antigen Genotyping on Platelet Engraftment and Graft-Versus-Host Disease after Hematopoietic Stem Cell Transplantation / 대한진단검사의학회지

BACKGROUND: Rapid platelet engraftment has several economic benefits by reducing the cost of supportive therapy as well as reducing the risk of fatal bleeding due to severe thrombocytopenia. Based on these considerations, we genotyped human platelet alloantigens (HPA) to evaluate the effect of minor transplantation antigen mismatches on the rate and speed of platelet recovery and clinical outcome of transplantation. METHODS: Thirty-five patients with various hematologic diseases transplanted between January 2001 and August 2004 were included. Genomic DNA was isolated from peripheral blood of donor-recipient pairs before transplantation. HPA-1, -2, -3, -4, -5, and -6 genotyping was performed by poly-merase chain reaction (PCR)-sequence specific primers (SSP). The effects of HPA compatibility on platelet recovery, incidences of graft-versus-host disease (GVHD) and relapse, and overall survival was investigated. RESULTS: There were no significant differences in platelet recovery according to HPA matching status. We observed no statistically significant differences in the occurrence of relapse and overall survival according to HPA-1, -2, and -3 matched/mismatched groups of patients, whereas HPA-3 mismatching was found to have a significant effect on GVHD development. There was also no difference in GVHD occurrence according to HPA-1 and -2 matched or mismatched transplants. CONCLUSIONS: Since platelet recovery in the HPA-1, -2, -3, and -5 matched/mismatched groups is not significantly different, the seems that platelet glycoprotein (GP) does not seem to act as a factor influencing the homing of hematopoietic stem cells. The finding that HPA-3 incompatibility may be involved in GVHD can be of importance. If a role for HPA-3 as minor histocompatibility antigens is confirmed by additional studies, we can ameliorate the outcome of allogeneic stem cell transplantation by typing of HPA and selecting the most closely related donors.