Vox Sanguinis最新文献

Background and objectives: Screening for transfusion-transmitted infections (TTIs) among blood donors is done using qualitative screening assays. Screening values that are close to cut-off values lie in the uncertainty zone, often denoted as the grey zone (GZ). This scoping review evaluated studies that have assessed the GZ reactivity by supplementary tests and its consequences.

Materials and methods: Studies evaluating GZ or indeterminate or inconclusive results for TTI screening among blood donors were searched using PubMed, Scopus and Google Scholar databases. Full text for the included articles was reviewed and analysed for study characteristics, TTI screening and GZ reactivity. This included GZ range, repeat or confirmatory testing, follow-up of such donors, effect on donor deferral and collected blood units.

Results: A total of 16 studies were included. GZ was evaluated for human immunodeficiency virus (HIV), hepatitis B virus (HBV), hepatitis C virus (HCV), syphilis, Chagas disease and human T-lymphotropic virus (HTLV). GZ values ranged from 0.5 to 1.2 times sample to cut-off (S/CO) values in different studies. The protocol for repeat/confirmatory testing was also heterogeneous. During repeat testing, many donors were found to be reactive or repeat GZ reactive. In confirmatory assays, the majority were negative, but many were positive or indeterminate. The protocol for donor follow-up and deferral protocols also varied significantly among different centres.

Conclusion: GZ evaluation showed a small yet significant risk of TTI from samples identified within the GZ range. There is further need for follow-up studies to establish TTI risk from repeat reactive or indeterminate samples, which will help in establishing uniform protocols for GZ samples.

Background and objectives: Allogeneic blood components and plasma-derived medicinal products (PDMPs) are cornerstone therapies in modern medicine, setting standards for quality, safety and efficacy. While platelets are traditionally transfused to prevent or control bleeding, they also serve as reservoirs of bioactive molecules with regenerative, anti-inflammatory, anti-oxidative and neuroprotective properties. This review examines how pooled human platelet lysates (HPLs) and platelet-derived extracellular vesicles (p-EVs) could be developed as therapeutic products, building on the principles established for PDMPs.

Materials and methods: We synthesize findings from preclinical and translational studies on the composition, production, mechanisms of action and clinical applications of HPLs and p-EVs, integrating insights from the PDMP industry to outline a framework for standardized development.

Results: Evidence indicates that HPLs and p-EVs from surplus or outdated platelet units show therapeutic potential in regenerative medicine, immunomodulation and drug delivery. Randomized trials in ocular graft-versus-host disease provide advanced clinical evidence, while other uses such as orthopaedics, wound healing and neurological disorders remain at exploratory or preclinical stages. Their development parallels the historical shift in plasma use, from transfusion to fractionation, offering a model for repurposing platelet concentrates (PCs). The systematic application of GMP, viral safety and regulatory frameworks can facilitate their clinical translation.

Conclusion: Platelet-derived products represent a new frontier for transfusion medicine, enabling value creation from surplus PCs. Ethical development, standardized production and stepwise clinical evaluation are essential to realize their promise in regenerative and precision medicine.

Background and objectives: Platelet-derived extracellular vesicles (PEVs) are submicron, membrane-bound particles released upon platelet activation, with a recognized role in haemostasis, inflammation and immunoregulation. PEVs remain insufficiently characterized in blood products. This study compared four isolation methods to evaluate their impact on PEV yield, purity and characteristics, aiming to identify a practical approach for transfusion service workflows.

Materials and methods: PEVs were isolated from expired single-donor aphaeresis platelet concentrates (n = 12) using methods based on different isolation principles: ultracentrifugation (UC), size exclusion chromatography (SEC), mixed size/charge separation (hybrid) and an affinity-based spin column method (affinity). Size, number and biochemical marker expression of all extracellular vesicle (EV) isolates were assessed.

Results: PEVs were successfully isolated by all methods, although at varying yields. The overall size distribution of all methods was similar, although SEC and affinity methods isolated PEVs with the largest diameters. PEV isolated by the affinity method had the lowest lipid:protein ratio, consistent with high purity. No differences in expression of EV marker CD9 or platelet activation marker CD42b were found.

Conclusion: Comparison of the physical and biochemical characteristics of the PEVs isolated by each method reveals that the affinity method was superior to other methods. In addition, its simplicity, cost effectiveness and accessibility make it a practical option for blood transfusion services to further explore the role of PEVs.

Human breast milk is the ideal source of nutrition for infants, especially for those who have premature births. However, all infants do not have access to human breast milk through their birth mothers for multiple reasons. Pasteurized donor human milk (PDHM), which is obtained from screened milk donors, is used to help nourish these babies. This is made possible by human milk banks (HMBs). Although there has been an increase in the number of HMBs globally, there is the possibility that growing demand could outpace the supply of PDHM. One way to overcome this is to use blood donation centres (BDCs) as HMB depots. There are several synergies that uniquely position BDCs to partner with or serve as depots to augment the availability of PDHM for infants in need. This may also come with certain hurdles including protocols for screening, processing and storage of milk products along with associated legal and regulatory challenges. It is imperative to establish clear guidelines regarding all these matters that could be used universally. Lastly, public awareness and education will be needed to promote and practically implement the idea of using BDCs as human milk depots. This will help eliminate any cultural or social obstacles. This article systematically examines those collaborations and the benefits, risks and challenges associated with BDCs operationally facilitating HMBs' capacity to supply PDHM.

Background and objectives: The presence of warm autoantibodies (WAAs) complicates pre-transfusion and compatibility testing. Despite attempts to provide antigen-matched red blood cells (RBCs), the risk of alloimmunization remains. Rates of alloimmunization and indications for transfusion were reviewed to streamline testing and RBC provision algorithms at a large tertiary care centre serving patients with lymphoid cancers and complex surgical needs.

Materials and methods: This retrospective observational study investigated the development of new RBC alloantibodies in patients with WAAs. This included 295,109 antibody screenings and 3129 antibody investigations (AIs) performed on 2493 patients between 1 September 2019 and 30 June 2024. AI results for patients with a history of WAAs were reviewed, along with diagnoses, transfusion data, and where applicable, phenotyping and genotyping results.

Results: Ninety-four patients had WAAs. Twenty-three of them (24%) had lymphoproliferative disorders (LPDs) and 21 (22%) required urgent antibody tests for surgical procedures. Fifty-one patients (54%) received RBC transfusions, and 30 of them (59%) had anaemia with haemoglobin below 70 g/dL. Thirteen patients (14%) required RBC genotyping because of recent transfusions or indeterminate results. The alloimmunization rate was 10%, including anti-Jk^a, anti-Kp^a, anti-Jk^b, anti-C^w, anti-Js^a and anti-Le^a, after RHDCE/K or more extended-matched RBC transfusions.

Conclusion: RBC alloantibodies develop in patients with WAAs, as the urgency of transfusions often limits the complete identification of antibodies and extended phenotype matching. With prompt investigation and RBC preparation, the risk of alloimmunization to major antibodies can be minimized.

Background and objectives: Natural disasters pose significant challenges to maintaining a continuous and safe blood supply. This study aimed to analyse the emergency response of the Turkish Red Crescent (TRC) blood services during the 2023 Turkey earthquake, focusing on blood supply continuity, donor mobilization and lessons learnt for future preparedness.

Materials and methods: A retrospective analysis was conducted using operational data from the TRC General Directorate of Blood Services. Information on blood component requests, supplies, donor mobilization, infrastructure status and personnel deployment was collected from the period immediately following the earthquake through the subsequent recovery phase.

Results: The earthquake severely disrupted blood service infrastructure in the affected provinces, resulting in the destruction of two blood collection units and damage to several facilities. Despite these challenges, the TRC successfully met demands from the transfusion centres through rapid activation of its Emergency Crisis Board, inter-regional redistribution of packed red blood cells and strategic donor management. Within 15 days, 250,708 blood units were collected nationwide-a 129% increase compared to pre-disaster levels. Controlled donation scheduling, proactive communication and inter-regional staff deployment ensured sustained operations and prevented overcollection. However, gaps in data interoperability between hospitals and TRC systems limited real-time monitoring of clinical blood usage.

Conclusion: The TRC's response demonstrated the effectiveness of a centralized and integrated blood service model in managing large-scale emergencies. Key lessons include the importance of donor flow regulation, transparent communication and improved hospital data integration to enhance future disaster preparedness and resilience.

Background and objectives: This study presents the results and experiences of bacterial testing of blood components (BCs) at the Croatian Institute of Transfusion Medicine during the period 2011-2024.

Materials and methods: During the 14-year period, 74,283 BCs were tested. Among these, 20,231 components (8345 red blood cell concentrates, 5729 platelet concentrates [PCs] and 6157 plasma units) were tested as part of statistical quality control (QC). In addition, 100% bacterial screening was implemented for aphaeresis platelets in November 2019 and for pooled platelets in October 2022 with 17,187 aphaeresis platelets and 36,865 pooled platelets tested by the end of 2024. All pooled platelets were tested using the large-volume delayed sampling (LVDS) method, whereas 9596 aphaeresis platelets were tested using the two-step method (from November 2019 to November 2022) and 7591 using LVDS (from November 2022 to December 2024). BCs were sampled and inoculated into both aerobic and anaerobic culture bottles and incubated at 36 ± 1°C for 7 days.

Results: As part of the statistical QC, 20,231 BCs (5729 PCs) were tested, resulting in a confirmed contamination rate of 0.09% (0.14% for PCs). Since the implementation of universal screening, 54,052 PCs have been examined, with a confirmed positivity rate of 0.18%. The most frequently detected organism was Cutibacterium acnes.

Conclusion: The confirmed positive rate of bacterial testing in our study and the isolates from positive cultures are comparable to similar studies. Active bacterial screening of BCs, among other measures, remains a critical step for preventing transfusion-associated bacterial infections.

Background and objectives: In July 2020, Brazil removed the long-standing restrictions on blood donation by men who have sex with men (MSM), shifting donor eligibility criteria towards individual behavioural risk assessment. We sought to establish the impact of this policy change on the safety of the blood supply.

Materials and methods: This retrospective cross-sectional study evaluated the prevalence and incidence of human immunodeficiency virus (HIV), hepatitis B virus (HBV), hepatitis C virus (HCV) and syphilis among blood donors at Fundação Pró-Sangue/Hemocentro de São Paulo. Data were analysed across two periods: before (P1: January 2019-June 2020) and after (P2: July 2020-December 2023) the MSM policy change. Prevalence was assessed in first-time donors, and incidence was calculated among repeat donors. The chi-square testing was used for statistical comparisons (p < 0.05).

Results: A total of 560,528 donations were included in the study. There were no significant differences in the prevalence per 100,000 donations of HIV (46.3 vs. 43.5; p = 0.77), HBV (33.3 vs. 27.7; p = 0.56) or HCV (94.1 vs. 72.6; p = 0.09) markers between P1 and P2. However, the prevalence of serological markers for syphilis increased significantly (745.7 vs. 1115.8; p < 0.0001) after the policy change. Donors with positive serological markers for syphilis in P2 were mostly younger and had higher education levels.

Conclusion: Lifting the MSM deferral policy in Brazil did not increase the prevalence or incidence of HIV, HBV or HCV markers among blood donors. The observed increase in the prevalence of serological markers for syphilis likely reflects broader population trends. These findings support risk-based donor screening as a safe and equitable approach to blood collection.

Background and objectives: Cord blood contains an array of microRNAs (miRNAs) regulating gamma globulin expression. However, miRNAs in exosomes from cord blood have not been reported yet. This study aims to analyse the differential expression of miRNA regulating fetal haemoglobin expression in cord blood exosomes and exosomes of maternal sample as control.

Materials and methods: This study includes exploration of putative gene targets for upregulation of fetal haemoglobin by bioinformatic tools such as MicroRNA Base (miRBase), MicroRNA Regulatory Network Analysis (miRNet) and MicroRNA Prediction (miRmap). The exosomes were isolated from EDTA sample of cord blood using a commercially available kit (Qiagen, GmbH, Germany). Total RNA was isolated from the exosome pellet by miRNA easy Mini Kit and SYBR green miRNA quantitative reverse transcription polymerase chain reaction (qRT-PCR) kit was used to validate the expression of miRNAs. The miRNAs of exosomes were analysed to see their presence or absence and fold changes in their expression in cord blood compared to the maternal sample as control.

Results: The cord blood exosomes showed a significantly increased expression of miRNA 15a-5p, 381-3p, 210-3p, 326 and 103a-3p in cord blood exosomes compared to exosomes of maternal plasma sample. However, the differential expression was not significant for miRNA 486-3p, 23a-3p, 27a-5p, 96-5p, 34a-5p, 23b-3p and let-7a-5p. Bioinformatically, significantly increased miRNA expression responsible for increased fetal haemoglobin (HbF) level was associated with B-cell lymphoma/leukemia 11A (BCL11A), Myeloblastosis (MYB), Kruppel-like factor-1 (KLF-1), Testicular Rreceptor 4 (TR4), Specificity Protein 1 (SP1) and SRY-Box Transcriptor Factor 6 (SOX6) genes.

Conclusion: This study finds the presence of potential miRNAs in cord blood exosomes regulating HbF level in cord blood. The results of this study may serve as the basis for future clinical trials to reactivate the HbF expression in sickle cell disease (SCD).

The application of technologies to inactivate pathogens in pooled plasma products is nowadays the standard. The number of blood centres applying these technologies to platelet concentrates is steadily increasing. However, pathogen inactivation (PI) of red cell concentrates and whole blood (WB) is challenging, as the haemoglobin-containing red cells quench light, and therefore require a different approach. Three technologies are currently under active development: S-303 (Intercept), UV-C (Theraflex) and riboflavin/UV (Mirasol). The S-303 technology is used for PI of red cell concentrates and has seen significant technical and clinical development in the last decade. Using this technology, red cell both ATP and haemolysis levels conform to objective requirements. For the UV-C technology, only one publication is available showing satisfactory quality of treated red cell concentrates in vitro. Lastly, the riboflavin and UV light technology is used on WB, and the in vitro data show room for improvement for red cell ATP and haemolysis levels. Part II of this review focuses on recovery studies and clinical trials that have been performed using pathogen-inactivated red cell concentrates.