ABSTRACT:Haploidentical allogeneic hematopoietic stem cell transplantation (h-HSCT) is increasingly used in patients lacking an HLA-matched donor. In this context, the combination of posttransplant cyclophosphamide (PTCy) and antithymocyte globulin (ATG) effectively prevents graft-versus-host disease, but its impact on the reconstitution of peripheral blood natural killer (NK) cell subsets remains insufficiently characterized. In this study, NK cell subsets were analyzed in depth in 56 adult recipients of unmanipulated h-HSCT with PTCy and ATG. Peripheral blood samples were collected at days +30, +60, and +100 after transplant. NK cell immunophenotype and cytotoxic function were assessed using multiparameter flow cytometry with unsupervised clustering, and degranulation assays against lymphoid and myeloid targets. Data were compared with those from 200 healthy volunteers. In spite of early numerical reconstitution, NK cells exhibited an immature immunophenotype with a low expression of activation markers. Cytotoxic activity against lymphoid targets was preserved, but degranulation against acute myeloid leukemia cell lines was significantly impaired across all NK subsets, including phenotypically mature NK cells. Cytomegalovirus reactivation was associated with an expansion of memory-like NK subsets but did not enhance degranulation. Functional education via killer cell immunoglobulin-like receptors was lost by day +30 and progressively reacquired from day +60 onward, in a pattern primarily influenced by the HLA-C genotype of recipients. These results indicate that, after h-HSCT with PTCy and ATG, NK cell subsets recover in number but fail to achieve early functional competence, particularly against myeloid targets. Strategies aiming at restoring mature NK cell functions warrant prospective investigations, especially in high-risk myeloid malignancies.
The retention of plasma donors is a major challenge for blood collection establishments. The literature shows that self-determination theory (SDT) presents a relevant conceptual framework for analysing the determinants of blood donation. This research aims to improve the understanding of the motivational mechanisms among donors. 277 French plasma donors (Mage = 43.21 years; SD = 13.83) responded to a French adaptation of the Blood Donor Identity Survey. Regressions were performed to predict intention to donate again, as well as subsequent donation behaviours. Controlling for age, gender and donation experience, autonomous motivation is positively associated with intention to donate again (β = 0.28, p < 0.001) and donation intention is a predictor of donor return (OR = 1.48, p = 0.032). Extrinsic motivation is not associated with either intention to donate again and donor return. These results illustrate the importance of developing strategies to foster donors' autonomous motivation for plasma donation.
BACKGROUND AND OBJECTIVES:Pathogen reduction (PR) using amotosalen-UVA was implemented for 100% of platelet concentrates (PCs) in France in November 2017. No bacterial testing was in place earlier. The impact of PR on the risk of transfusion-transmitted infections (TTIs) from November 2017 to December 2022 (vs. January 2013 to October 2017) has been published previously. To further assess the impact of PR implementation, the evaluation period was expanded to December 2024. MATERIALS AND METHODS:PC-associated TTIs occurring in 2023 and 2024 were analysed and included in the assessment. RESULTS:Two cases of PC-associated transfusion-transmitted bacterial infections (TTBIs) were reported. The first involved Bacillus mobilis in a split pooled whole blood-derived PC. This Grade 2 TTBI was diagnosed following identification of the same pathogen in the second PC unit, quarantined for failed swirling test. The second involved Staphylococcus ureilyticus in an apheresis PC transfused to a patient who subsequently died. TTBI frequency decreased from 1/97,098 PC (n = 15 over 5 years, 2 deaths) to 1/787,662 PC (n = 3, over 7 years, 1 death) after PR implementation (p < 0.001). No human immunodeficiency virus (HIV), hepatitis B virus (HBV), hepatitis C virus (HCV), human T-cell lymphotropic virus (HTLV) or arboviruses TTI were reported from 2013 to 2024. No further cases of PC-associated hepatitis E virus (HEV) TTI were reported, concomitantly to HEV-nucleic acid testing implementation. A PC-associated parvovirus B19 TTI occurred in 2024. The use of PR PCs facilitated PC supply during arboviral outbreaks. CONCLUSION:The reduction in PC-related TTBIs following PR implementation is confirmed. However, the recent occurrence of two severe TTBI cases highlights a persistent risk. Prevention of PR-PC-associated TTIs by non-enveloped viruses requires specific screening.
BACKGROUND AND OBJECTIVES:To meet the long-term demand for blood products while preserving donor health in the long run, blood establishments must recruit a sufficient number of new donors annually. To determine what will suffice, it is essential to be able to forecast future blood donation volumes as a function of new donors using estimates based on historical donation activity. MATERIALS AND METHODS:Donor (n = 11,629,873) and donation data (n = 64,510,294) extracted from operational information systems of seven blood establishments were transformed into anonymous donation activity data (grouped by blood establishment, sex and blood group) in the form of time series of mean number of donations per donor, indexed by years since first donation. Linear models were fitted to the time series using ordinary least squares. RESULTS:Out of the various estimated models, the best fit (mean R2 over blood establishments 99.95%) for past mean donation activity was achieved when regressing the logarithm of cumulative donation activity on the logarithm of years since first donation and an indicator variable for the year of first donation. In addition to the predictions, comparison of the estimated parameters revealed that there are significant differences between blood establishments, translating to differences in the expected number of donations accumulated over the lifetime of a donor. CONCLUSION:Average donation activity can be modelled using a few variables and simple models, with high precision. The estimates can be used to create forecasts of future donation volumes, which in turn can be useful in long-term blood donation management.
