Vox Sanguinis最新文献

Background and objectives: Severe transfusion reactions to group B-incompatible platelets and plasma possibly related to the α-gal syndrome (AGS) have been recently described. AGS is a potentially severe Immunoglobulin E mediated allergy to mammalian meat and meat-derived products associated with tick bites. The involved allergen, galactose-α-1,3-galactose (α-gal), is antigenically similar to the blood group B antigen. To further assess a potential association between AGS and allergic transfusion reactions (ATRs), we comparatively assessed the frequency of ATRs after plasma or platelet concentrate (PC) transfusion in relation to the degree of ABO compatibility between the recipient and the involved blood component in France.

Materials and methods: In France, all transfusions are centrally recorded, and ATR reporting is mandatory. Frequencies of severe ATRs involving PC or plasma in relation to ABO group distributions were analysed between 1 January 2022 and 31 December 2024.

Results: Among 981,955 PC and 580,230 plasma evaluable transfusions, severe ATRs were significantly higher in group O recipients transfused with group B or AB platelets (relative risk [RR]: 5.06, 95% confidence interval [CI]: 3.27-7.83, p < 0.001) and plasma (RR: 2.15, 95% CI: 1.37-3.36, p < 0.001) while not in group A recipients of group B or AB platelets (RR: 0.95, 95% CI: 0.30-2.96) or plasma (RR: 0.92, 95% CI: 0.45-1.88), when compared to ATR rates in all other recipients of PC or plasma, respectively.

Conclusion: In this national retrospective haemovigilance analysis, group B or AB PC or plasma transfused to group O recipients is associated with an increased risk of severe ATRs. Further studies will establish whether AGS is involved in this increased risk.

Background and objectives: Early balanced transfusion is recommended for resuscitation of patients with severe bleeding. Whole blood (WB) is reintroduced as a feasible alternative to blood components, as it includes red blood cells, plasma and platelets in a physiological ratio.

Materials and methods: In this review, we aim to provide practical guidance and a framework for blood providers aiming to implement a WB programme. The review summarizes recommendations and practical implications identified from published literature, regulatory requirements and current programmes.

Results: WB donors are selected based on national donor selection criteria. When the patients' ABO-type is unknown, low titre anti-A and anti-B group-O WB (LTOWB) are recommended. ABO-group type-specific blood can be used in patients with known ABO type. Anticoagulants include CPD and CPDA-1. Leukoreduction can be performed with a platelet-sparing filter. WB is stored at +2 to -6°C for up to 35 days. Rotation of the stock and re-manufacturing to red cell concentrates minimizes outdating. The EDQM Guide to the preparation, use and quality assurance of blood components provides the minimum requirements. Post-implementation follow-up includes haemovigilance and quality surveillance. End users should be involved in the development of the programme and training of personnel. Emergency collection of WB can enable transfusion to patients in remote areas, during disasters and during war.

Conclusion: We conclude that implementation of a WB programme for routine and emergency management of patients with severe bleeding can be performed in a structured, safe and sustainable way.

Background and objectives: Although COVID-19 convalescent plasma (CCP) has been successfully used to treat several viral infections, its effectiveness in neutralizing severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) and its broader immunological safety remain debated. Since viral infections can trigger autoimmunity, particularly through molecular mimicry and immune dysregulation, there is growing interest in understanding whether CCP contains autoantibodies that could affect recipient safety.

Materials and methods: In this study, we evaluated the presence of 20 different autoantibodies, along with anti-SARS-CoV-2 antibodies, in plasma samples from CCP donors. Samples were collected at three time intervals following COVID-19 symptom onset: 0-60, 60-120 and 120-180 days. Results were compared with those from healthy control plasma donors.

Results: Several autoantibodies- anti-Smith (anti-SM), anti-Sjögren syndrome antigen A, 60-kDa isoform (anti-SSA/Ro60), anti-proliferating cell nuclear antigen (anti-PCNA), anti-Ribosomal P and anti-ribonucleoprotein/Smith antigen complex (anti-RNP/SM)-showed modestly elevated levels in CCP samples collected within 0-60 days post symptom onset. In the 60-120-day period, autoantibody levels declined and approached levels observed in the control group. In the 120-180-day period, most autoantibody levels remained comparable to control levels. Our analysis showed no significant correlations between levels of neutralizing SARS-CoV-2 antibodies and autoantibody concentrations nor significant differences in autoantibody profiles between donors with high and low neutralizing antibody (NAb) titres.

Conclusion: Our findings suggest that SARS-CoV-2 infection may transiently elevate certain autoantibodies in CCP donors. However, most autoantibody levels decline over time and the overall profiles do not indicate sustained autoreactivity. These results support the immunological safety of CCP, particularly when collected between 60 and 120 days post infection, and highlight the importance of timing in optimizing both efficacy and safety in plasma donation strategies.

Background and objectives: Iron deficiency (ID), with or without anaemia, affects over 1 billion people globally. Early detection is essential, but current diagnostic tools may be costly, logistically complex and not widely accessible. This study evaluates low haemoglobin density percentage (LHD%), derived from mean corpuscular haemoglobin concentration (MCHC) in routine complete blood counts (CBCs), as a no-added-cost, accessible alternative for ID screening.

Materials and methods: We retrospectively analysed 3526 adult patient records (January-April 2025) from a single-centre institution, including those with iron panel and CBC performed within 24 h. Patients were categorized as Normal, ID, ID anaemia (IDA) or anaemia without ID (AwoID). LHD% was calculated and assessed across groups using receiver operating characteristic (ROC) curve analyses for cutoff determinations.

Results: Median LHD% increased progressively from the Normal group (2.99%) to the IDA group (6.71%). ROC analysis showed modest but acceptable diagnostic performance: area under the curve (AUC) was 0.677 overall, 0.687 in non-anaemic and 0.684 in anaemic subjects. Specific LHD% cutoffs varied by context: >4.48% for general screening (61% sensitivity, 67% specificity), >7.02% for donor screening (95% specificity) and >3.74% for anaemia workup (75% sensitivity).

Conclusion: LHD% shows potential as a context-specific, no-added-cost screening tool for ID using existing CBC data. While its diagnostic performance is modest, its scalability and accessibility could support broader public health screening efforts. Further prospective validation is recommended.

Background and objectives: The demand for intravenous immunoglobulin (IVIG) is increasing, but supply is limited. Some residual protein contaminants such as prekallikrein activator (PKA) and immunoglobulin A (IgA) can cause severe adverse effects, necessitating a more efficient purification process with high recovery and fewer impurities.

Materials and methods: We used IVIG intermediate from caprylic acid precipitation as the starting material. Diatomite adsorption and two-step anion exchange chromatography (AEX) were employed to remove PKA, Factor XII, prekallikrein and kallikrein. Three resins for the second-step flow-through mode AEX were evaluated, and the loading conditions were optimized by Design of Experiments (DoE) and high-throughput screening experiments to better remove IgA and immunoglobulin M (IgM). Pilot-scale experiments validated the feasibility of the optimized process.

Results: Diatomite adsorption (300 g/kg, 1 h) and two-step AEX could remove PKA, Factor XII, prekallikrein and kallikrein to below the limit of detection. The best AEX resin and optimal loading condition (pH 6.0 with 3.0 mS/cm conductivity) to remove IgA and IgM were obtained. As a result, IgA and IgM could be reduced to 3.83 and 10.70 μg/mL, respectively, with the immunoglobulin G (IgG) recovery over 86.9%. The 800-L pilot-scale results demonstrated successful process scale-up, achieving robust IgG recovery and effective impurity removal for IVIG production.

Conclusion: The combination of diatomite absorption and optimized two-step AEX resulted in IVIG preparation with enhanced purity and high recovery.

Three technologies are currently under active development for pathogen inactivation of red cell concentrates or whole blood (WB): the Intercept technology using S-303 as an inactivating chemical; the Theraflex technology using UV-C illumination; and the Mirasol technology using riboflavin and UV light. For the UV-C technology, no in vivo data are available. For the other two technologies, recovery, survival and life span of the treated red blood cells (RBCs) are shortened but are within objective requirements, including a 24-h recovery >75%. S-303-treated RBCs were transfused in various patient groups and, so far, showed no relevant differences in the clinical endpoints. In early studies, S-303-reactive antibodies were observed, which prompted changes in the inactivation process, and no further antibody formation was seen. The one published study with the riboflavin/UV procedure showed good effectiveness of treated WB, with haemoglobin increment similar to that of untreated WB. When considering potential implementation of pathogen inactivation strategies, a balance should be struck between microbiological safety, component quality and cost. None of the current technologies is in a stage for large-scale blood bank application, either because of limited availability of evidence of satisfactory in vitro quality data or because of the ongoing requirement of clinical trials in a broad spectrum of patients.