Apheresis Donors Research Articles

P‐BB‐68 | Reference Ranges for Complete Blood Count in Platelet Apheresis Donors at an Intermediate Altitude

P‐BB‐68 | Reference Ranges for Complete Blood Count in Platelet Apheresis Donors at an Intermediate Altitude

Lipidomic analysis of differently prepared platelet concentrates in additive solution during storage.

Structural and biochemical changes in stored platelets are influenced by collection and processing methods. Lesions may appear during platelet concentrate storage, some of which may be involved in adverse transfusion reactions. The preparation and storage of platelet concentrates (PC) may modify and even damage the lipid mediator content. The aim of this study was to investigate the lipidomic profile identified in the supernatants of PCs according to processing and storage conditions, both after leukocyte filtration and contained in platelet additive solution (PAS), comparing single donor apheresis (SDA) products with pooled buffy coat (BC) products. We investigated the accumulation of various lipid mediators including lysophospholipids (LP) and eicosanoids in SDA and BC products stored for 0-5 days. All products were processed following French Blood Establishment (EFS) procedures in accordance with EDQM/GTS European Standards. Both SDA and BC were leukocyte reduced and conserved in 35% autologous donor plasma and 65% platelet additive solution. Lipidomic analysis was performed on PC supernatants using LS/MS spectrometry. Our data demonstrate that lysophosphatidylcholine (LPC) levels were higher in BCs compared to SDAs, with no difference in lysophosphatidic acid (LPA) expression between the two preparation methods. Results for other eicosanoids showed greater similarity; indeed, no clear pattern emerged from analysis of eicosanoids in terms of storage time and process. In general, we observed longitudinal lipid mediator modulation for both SDAs and BCs, particularly at later time points. The expression of LPC and some eicosanoids in BCs could be used as novel biomarkers of PC quality. Future studies are needed to explore their impact on adverse transfusion reactions.

Survey on the usage of therapeutic erythrocytapheresis in transfusion services in Italy for the treatment of polycythemia vera, secondary erythrocytosis and hemochromatosis.

IntroductionErythrocytapheresis, an apheresis treatment which selectively removes red blood cells, is an alternative to therapeutic phlebotomy, over which it has several advantages.Actually there is a high degree of variability in the use of this treatment. This prompted SIdEM (Italian Society of Hemapheresis and Cell Manipulation) to conduct a survey on the use of erythrocytapheresis in the Italian Transfusion Services. The purpose is to monitor this activity in the treatment of Polycythemia Vera (pv), secondary erythrocytosis and hemochromatosis. Materials and methodsA data collection file was sent to the SIdEM regional delegates who, in turn, involved the Transfusion Centers in the areas they cover. The data collected were processed on a Microsoft Excel spreadsheet. Results75 centers from 14 Italian regions responded to the Survey: 36 centers (48 %) use erythrocytapheresis (35 centers perform therapeutic apheresis and 1 center only donor apheresis), 39 centers (52 %) do not (15 centers perform therapeutic apheresis, 18 centers only donor apheresis and 6 centers do not perform either therapeutic apheresis or donor apheresis).Although most centers have a substantially uniform attitude concerning the indications for which erythrocytapheresis is used, the survey shows that there are still differences more evident in the treatment of secondary erythrocytosis than in the treatment of pv or hemochromatosis. ConclusionsThis survey has been useful to document the current Italian reality and to raise awareness about the need for improvement in optimizing and standardizing the use of a therapy with a great potential to exploit properly.

Plateletpheresis donor deferral patterns at a tertiary care hospital in North India: A need for rethink of haemoglobin cutoff.

The donor deferral criteria for blood or apheresis donations are established for two main reasons: (i) to ensure the safety of the blood donor (non-maleficence); (ii) to obtain safe blood of standard quality that has therapeutic benefit for the patient (beneficence). This study was planned to assess the various causes and patterns of plateletpheresis donor deferral in our hospital and to subsequently assess whether any evidence based changes can be done in the current plateletpheresis donor deferral criteria in India to maximize the platelet donor pool without compromising donor safety. The present study was conducted from May 2021 till June 2022 in the department of transfusion medicine of a tertiary care hospital in North India. The first part of the study was conducted from May 2021 till March 2022 to assess the various causes of donor deferral by analysing the plateletpheresis donor deferral data during the corresponding period. The second part of the study was conducted from April 2022 till June 2022, to assess: (i) average decrease in haemoglobin after plateletpheresis procedure; (ii) red blood cell loss during plateletpheresis procedure; (iii) to determine whether any correlation exists between donor haemoglobin and platelet yield. During the study period, a total of 260 donors were screened for plateletpheresis, out of which 221 (85%) donors were accepted and 39 (15%) donors were deferred for various reasons. Out of the 39 deferred donors, 33 (84.6%) were temporary deferrals, while 6 (15.4%) were permanent deferrals. Low haemoglobin (Hb<12.5g/dl) was a cause of deferral in 12.8% (n=5) of the deferred donors. 192 (73.9%) out of the 260 donors were replacement donors. The calculated mean decrease in haemoglobin as a result of plateletpheresis procedure was 0.4g/dl. No correlation was seen between donor pre-donation haemoglobin and platelet yield (p=0.86, r=0.06, R2=0.003). The calculated mean red cell loss as a result of plateletpheresis procedure was 28ml. Low haemoglobin (<12.5g/dl) is a significant cause of temporary plateletpheresis donor deferral in India. In view of the advancement in plateletpheresis technology, which has resulted in minimal red cell loss with the current generation apheresis devices, haemoglobin cutoff of 12.5g/dl needs to be reconsidered. Perhaps, after performing a multi-centric trial, a consenscus can be reached for revision of haemoglobin cutoff for plateletpheresis donations.

Abstract 240: Bioactive Lipids In Circulation: Biomarker Of Ageing?

Blood transports cells and nutrients. However, it is less known that the major plasma compound is the lipid family in the broad sense. Among these lipids, cholesterol, triglyceride but also the family of polyunsaturated fatty acids (PUFAs) and their metabolites. These lipid mediators are involved in several chronic, inflammatory diseases such as rheumatoid arthritis. But, ageing is associated with chronic inflammation and affects almost 20% of the world’s population. Thus, it is by far the most important population before cardiovascular disease and cancer. Using mass spectrometry analyses, we evaluated the levels of different classes of lipid mediators from healthy young and elderly donors (single donor apheresis). Our data showed a significant decrease of lysophosphatidic acid species‘s expression, modulation of the 5-lipoxygenase product’s, as well as lipid mediators derived from PUFA oxidation. Their effect on blood vessel and circulating cells influenced their function. Indeed, lipid mediator intake is involved in transfusion reactions, and we observed an activation of blood cells, especially platelet, with significant increase of p-selectin. These data highlighted the importance of lipid mediator level in a context of transfusion and ageing of blood donor independently of the storage time of single donor apheresis. They can serve as biomarker of ageing.

Review and assessment of the donor safety among plasma donors.

Review and assessment of the donor safety among plasma donors.

Bioactive lipids as biomarkers of adverse reactions associated with apheresis platelet concentrate transfusion.

Platelet concentrate (PC) transfusion seeks to provide haemostasis in patients presenting severe central thrombocytopenia or severe bleeding. PCs may induce adverse reactions (AR) that can occasionally be severe (SAR). PCs contain active biomolecules such as cytokines and lipid mediators. The processing and storage of PCs creates so-called structural and biochemical storage lesions that accumulate when blood products reach their shelf life. We sought to investigate lipid mediators as bioactive molecules of interest during storage and review associations with adverse reactions post-transfusion. To facilitate understanding, we focused on single donor apheresis (SDA) PCs with approximately 31.8% of PCs being delivered in our setting. Indeed, pooled PCs are the most widely transfused products, but the study of a single donor lipid mediator is easier to interpret. We are investigating key lipid mediators involved in AR. Adverse reactions were closely monitored in accordance with current national and regional haemovigilance protocols. Residual PCs were analysed post-transfusion in a series of observations, both with and without severe reactions in recipients. A decrease in the lysophosphatidylcholine species to produce the lysophosphatidic acid species has been observed during storage and in the case of AR. Lysophosphatidic acid increased with primarily platelet-inhibitor lipids. Anti-inflammatory platelet-induced inhibition lipids were weakly expressed in cases of severe adverse reactions. We therefore propose that a decrease in lysophosphatidylcholine and an increase in lysophosphatidic acid can prospectively predict serious adverse transfusion reactions.

Prospective, open-label, multicenter clinical study to assess the performance of a new donation system for the collection of source plasma.

Safe, efficient, and reliable innovations among donation systems are needed to meet the growing global demand for source plasma. This study assessed the ability of a new donation system to collect appropriate product weights based on the US Food and Drug Administration nomogram for source plasma collections. Procedure duration and safety endpoints were also collected. The Rika Plasma Donation System (Terumo BCT, Inc., Lakewood, CO) was evaluated in a prospective, open-label, multicenter study. Healthy adults meeting FDA and Plasma Protein Therapeutics Association requirements for source plasma donor eligibility were consented and enrolled in the study resulting in 124 evaluable products. The target product collection weights (ie, including plasma and anticoagulant) by participant weight category were: 705 g (110-149 lbs), 845 g (150-174 lbs), and 900 g (≥175 lbs). The mean reported product collection weights by participant weight category were 705.0 ± 0.00, 845.0 ± 0.20, and 899.9 ± 0.31 g, respectively. The mean overall procedure time was 31.5 ± 5.41 minutes. The mean procedure times by participant weight category were 25.6 ± 3.13, 30.5 ± 4.45, and 33.7 ± 4.80 minutes, respectively. Procedure-emergent adverse events (PEAEs) occurred in five participants. All PEAEs were consistent with known risks for apheresis donation, and none were related to the donation system. The new donation system collected the target product collection weight in 100% of evaluable products. The mean procedure collection time was 31.5minutes. The system is a new efficient platform that consistently collects the appropriate weight of the source plasma.

Transfusion Effectiveness of Single Donor Apheresis Platelet over Random Donor Platelet; A Comparative Study

Background: Platelet transfusion performs a key function in treatment for patients with thrombocytopenia. The use of single donor apheresis platelet results in better post-transfusion recovery &amp; survival than random donor platelet. Activation of platelet depends on their preparation and storage and this may be one of the factors responsible for storage related change in platelet membrane proteins. In transfusion medicine laboratory we commonly prepare platelet concentrates from whole blood, platelet rich plasma, buffy coat and single donor plateletpheresis. Objective: The aim of the study was to evaluate the transfusion effectiveness of single donor apheresis platelet over random donor platelet. Methods: This is an observational study. This study was carried out on 125 dengue patients the find out about the population including male and female patients in the Department of Transfusion Medicine, Bangabandhu Sheikh Mujib Medical University, Chittagong Medical College Hospital, Bangladesh and Samorita Hospital &amp; Medical College, Dhaka, Bangladesh. The duration of the period from July 2021 to December 2022. The period from data was entered in MS Excel and Statistical analysis was done using SPSS-24. Results: The total study population was 125 patients aged 10 – 40 years, 17(13.6%) were ≤10 years, 49(39.2%) were 11-20 years, 37(29.6%) were 21-30 years and 22(17.6%) were 31-40 years. Sex distribution of the population where, 85(68.0%) were male and 40(32.0%) were female. Conclusion: Single-donor apheresis platelet transfusions produced higher platelet counts, whereas random donor platelet also effective in preventing hemorrhage.

The impact of transshipment on an integrated platelet supply chain: A multi-stage stochastic programming approach

This paper presents a multi-stage stochastic optimization model to minimize total cost under centralized control for a multi-echelon platelet supply chain which takes into account transshipment, demand uncertainty, stock age information, two types of supply, and three types of patients. The objective is to study the impact of transshipment between hospitals on performance improvement using a multi-stage stochastic framework to capture dynamic demand so as to explore approaches to improve an integrated platelet supply chain. Applicability of the model is tested through a real-world platelet supply chain with one blood center, three collection facilities, and five hospitals. The proposed multi-stage stochastic model is shown to perform better than a two-stage stochastic program in handling random daily demand and it also shows transshipment helps with alleviating shortage and wastage and reallocating stock at hospitals to improve system cost efficiency. Further, sensitivity analysis indicates that recruiting more apheresis platelet donors at hospitals and maintaining an initial inventory level that is close to the daily demand of hospitals are efficient strategies to improve performance of the platelet supply chain. In addition, we observed that imposing a FIFO issuing policy is not necessary for achieving optimal performance. These findings suggest that administrators and decision makers can improve cost efficiency in the platelet supply chain by implementing transshipment between hospitals, recruiting more donors, maintaining a suitable inventory level, and making collection and production plans in a shorter stage length.

Validity of donor-reported iron supplementation practices obtained at the time of donation.

Iron supplementation (IS) improves blood donors' iron stores and allows more frequent blood donation. Understanding the accuracy of self-reported IS is helpful for potential application of IS practices to donor eligibility or donation intervals. Successful whole blood and red cell apheresis donors completed a survey at donation on the use of select dietary supplements. Respondents reporting use of either iron pills (IP) or multivitamins (MV) were invited by email to complete a similar follow-up survey 6-8 weeks later and to provide the quantitative iron content of IS by referring the donor to the pill bottle label. Consistency between baseline and follow-up responses was assessed overall and by pill type and demographic variables. Of 2444 donors answering the baseline survey, 40% (978) reported MV or IP at donation, 354 of whom completed the follow-up survey. A majority of survey respondents (56%-61%) reported taking iron across the two surveys, and 21%-24% took MV but were uncertain if their pills contained iron. Of 215 reporting IS at baseline, overall concordance at follow-up was 68% and was higher for donors who were female, ≥50-years old, and taking iron as an iron pill rather than in a multivitamin. Consistency of donor responses may be insufficient for use in guiding donor eligibility. Referring donors to their pill bottles was unsuccessful in improving the high frequency of uncertain responses. Incorporating IS into donor eligibility determinations is a complex endeavor that will benefit from careful planning and from post-implementation monitoring.

Hemolysin test as a tool to screen high-titer Group O platelet apheresis donors: A prospective study.

Minor ABO-incompatible apheresis platelet transfusion poses a risk of hemolytic transfusion reactions in non-Group O recipients when donor's plasma possesses unusual high titers for anti-A and anti-B. The aim was to determine whether the hemolysin test can be used as a screening tool to predict high-titer Group O platelet apheresis donors. A prospective study, with Group O platelet donor's samples, was tested for hemolysin test and antibody titration test in parallel. Antibody titration was also performed on products suspended in platelet additive solution (PAS). Hemolysin test was assessed for diagnostic accuracy against antibody titration. Chi-square test and Mann-Whitney U-test were used to determine the relationship between the hemolysin test and antibody titration. Among 107 Group O platelet donations, median anti-A and anti-B titers in donors were 32 (8-128) and 32 (4-256), respectively. High titer (≥128) for ABO antibodies was seen in 18% of donations, whereas hemolysin test was positive in 69% of donations. Hemolysin test results differ significantly with antibody titration results (P = 0.03). Hemolysin test had higher sensitivity (89%) with a strong negative predictive value (94%). None of the products suspended in PAS had high-titer antibodies. Adopting hemolysin test as a screening tool may label a large number of units (69%) unsuitable for ABO-incompatible platelet transfusion. Alternatively identifying donors with high antibody titer or positive hemolysin test and selectively suspending their product in PAS may be a cost-effective approach and certainly prevent high-titer antibodies in the product.

ADVERSE EVENTS ASSOCIATED WITH PLATELETPHERESIS: A PROSPECTIVE STUDY FROM A TERTIARY CARE HOSPITAL.

Plateletpheresis is used to obtain platelets from volunteer donors, patient's family members,or donor with HLA or platelet antigen compatible phenotypes. To analyze the adverse reactions due to single donor platelet Aim: pheresis. Materials and Methods:This was a prospective observational study conducted over a period of one year from September 2018 to August 2019 in the department of Immunohematology and Blood Transfusion Medicine, GMC Jammu. A total of 157 plateletpheresis procedures were performed after taking informed and written consent from the donor. The donors were selected as per the guidelines of Director General of Health Services (DGHS). Single arm procedure was used.All the procedures were performed on Fresenius kabiCom.tec op 5/07.08 by intermittent flow centrifugation (IFC). The adverse events (AE's) were classified as donor related and kit/equipment related. A total Results: of 10 AE's were noted of which 6 (60%) events were associated with donors and 4 (40%) events were owned to fault in the kit/equipment.Donor related 6 AE's include citrate toxicity[n=3(50%)], vasovagal reactions [n=2(33.33%)] and hematoma [n=1(16.67%)].Machine related 4 AE's include leakage in the kit[n=3(75%)] and interface error [n=1(25%)]. Discussion and Conclusion: Our study showed (n=6)3.82% donor reactions and equipment related (n=4) 2.54% reactions. Apheresis donations performed on cell separators are safe. The percentage of reactions in our study was 6.36% and no serious adverse reaction was noted .But precautions and close monitoring helps to reduce such mild forms of reactions.Increasing demand of platelet transfusions for patients had led to accelerated use of Apheresis, cause of higher yield of platelets obtained from single donor.

Pre-Clinical Investigation of a Novel Small Molecule Inhibitor Targeting YBX1 in AML

Recently, our group identified the pleiotropic DNA and RNA binding protein YBX1 as a specific dependency and therapeutic target in acute myeloid leukemia (AML) that is essential for stabilizing oncogenic transcripts and thereby maintains oncogenic protein expression (Perner et al., 2021). Selective pharmacologic targeting of YBX1 in AML, however, has not been achieved so far. Here, we investigate the functional consequences of a novel small molecule inhibitor (SU056) of YBX1 in AML. We examined the viability of several human AML cell lines (MOLM13, HL60, EOL1, THP1, Kasumi1, ML2, Mv4;11, OCI-AML3, NOMO1) upon SU056 treatment and found significant reduction of cell growth in a concentration dependent manner. Inhibition of cell growth could be mainly attributed to impaired proliferative capacity at nanomolar concentrations. Pharmacologic inhibition of YBX1 resulted in impaired colony formation (mean colony number DMSO: 231.3±13.88 vs. SU056 500nM: 154.7±8.29; p<0.0001), cell cycle arrest (cells in S phase: DMSO: 37.3±2.4 vs. SU056 500nM: 27.2±1.67; p=0.0127) and induction of myeloid differentiation. Consistently, in a xenograft model of human AML, SU056 treatment resulted in prolonged disease latency (MOLM13 diluent: 62 days OS vs. SU056: not reached, p=0.0013; OCI-AML3 diluent: 79 days OS vs. not reached, p=0.0001) and significant reduction of disease penetrance (MOLM13 diluent: 100% vs. SU056: 24,9%; OCI-AML3 diluent: 100% vs. SU056: 9,1%). Consistently, percentage of SU056 treated human leukemic cells in the bone marrow of recipient mice was decreased for both, MOLM13 (mean diluent: 41,3% vs. SU056: 7,6%) and OCI-AML3 (mean diluent: 28,9% vs. SU056: 2,9%). Likewise, pharmacologic inhibition of YBX1 reduced colony formation and total cell numbers of primary human AML cells in a dose-dependent manner. To be clinically relevant, such treatment must have a suitable therapeutic index between human hematopoietic stem- and progenitor cells (HSPCs) and their malignant counterpart. This is particularly important, considering the role of YBX1 in mRNA splicing and processing. Of note, pharmacologic inhibition of YBX1 did not perturb colony formation of normal HSPCs derived from apheresis donors. These findings were confirmed by investigating primary human leukemic cells in a patient-derived xenograft (PDX) model of AML. We aimed to assess whether loss in leukemia cell competition induced by pharmacologic targeting of YBX1 is sufficient for normal hematopoietic cells to outcompete leukemic cells in vivo. 1x106 normal human HSPCs were transplanted along with 2x104 leukemic cells to assess for efficacy of SU056-treatment versus diluent control. In vivo treatment with SU056 (20mg/kg, i.p.) for 3 weeks resulted in a significant decrease in the AML blast number in the PB (mean blast %: diluent: 38.5%; SU056: 2.25%; p<0.0001). This resulted in increased survival of SU056 treated recipients (OS diluent: 83 days vs. SU056: not reached). To confirm the proposed mechanism by which SU056 impairs leukemia growth we performed global transcriptome and proteome analysis following treatment with SU056 (500nM, 96h). Proteome profiling revealed a total of 2641 deregulated proteins. Gene-ontology analysis indicated deregulation of YBX1 targets and proteins associated with cell cycle, DNA repair, mRNA splicing/processing, and transcriptional regulation. Of note, overlap between transcriptional regulation (as determined by mRNA-Seq) and changes in proteome abundance revealed less than 5% target genes/proteins, indicating that SU056 may in fact interfere with binding of oncogenic mRNAs to YBX1 and thereby may reduce translation of oncogenic transcripts. In order to define functional consequences of pharmacologic YBX1 inhibition and explore potential vulnerabilities of drug combinations, we performed a genome-wide CRISPR/Cas9 screen in human AML cells treated with SU056 versus diluent control. Validation experiments are currently ongoing. Taken together, our data confirm the therapeutic potential to target YBX1 using the novel small molecule SU056. Given its broad applicability across genetic subtypes of AML and lack of toxicity on normal HSPCs, SU056 as a single agent or in combination with established targeted therapies may efficiently help to target and outcompete leukemic cells. Experiments to assess for potential synergy with already established targeted therapies will be presented.

Factors Predicting Efficacy and Toxicity of Post Transplantation Cyclophosphamide for Graft Versus Host Disease Prevention in Hematopoietic Cell Transplantation Recipients: Interim Data of an Ongoing Study

Introduction: Post-transplant cyclophosphamide (PTCy) following allogeneic stem cell transplantation (allo HCT) to decrease the risk of graft vs host disease (GVHD) has transformed the field. Since initially demonstrating safety and efficacy following non-myeloablative (NMA) conditioning in patients (pts) receiving haplo-identical donor (haplo) transplants, PTCy has been implemented in matched related donor (MRD), matched unrelated donor (MUD), and mismatched unrelated donor (mMUD) transplantation. However, PTCy can contribute to toxicity, and some pts still develop GVHD. A personalized approach to PTCy dosing could provide more effective prevention of GVHD and less toxicity without compromising graft versus tumor activity. We present interim results of our study investigating the genetic and metabolic factors that modulate Cy metabolism and the extent to which these drive its immunomodulatory effects. Methods: All adult pts receiving allo HCT with MRD, MUD or haplo donor were eligible. All recipients received NMA preparative regimen which included Cy 14.5 mg/kg on days -6 / -5 and PTCy (50 mg/kg) on days +3 / +4. Pts underwent standard clinical evaluations post-transplant for up to 2 yrs. This study was IRB approved and registered under NCI clinical trial (NCT03555851). Pharmacogenomics (PG): Recipient's germline DNA was extracted from buccal swabs obtained prior to transplant. Candidate genes genotyped using next-generation sequencing included CYP2B6, CYP3A4/5, CYP2C8/9, CYP2C19, ALDH1A1/3A1, GSTP1, GSTM1, and GSTA1. Pharmacokinetics (PK): Blood samples were obtained on day -6 and day +3 within 15 minutes after the end of Cy infusion, and 2, 4, 8, 16, 20, and 24 hours (hrs) after infusion start. Concentrations of Cy and its metabolites hydroxycyclophosphamide (HCY) carboxyethylphosphoramide mustard (CEPM) and phosphoramide mustard (PM) were analyzed using a Waters Quattro Premier triple quadrupole mass spectrometer coupled to an Acquity UPLC system. Immune Profiling (IP): Mononuclear cells were isolated and cryopreserved from haplo donor apheresis products as well as from pts prior to transplant on day -6, day 0, and post-transplant days +3, +5, +14, +30, and 3, 6 and 12 months (mos) post-transplant. Immune effector and memory subsets surveyed by flow cytometry included: CD4, CD8 T cells and regulatory T cells (Treg). Descriptive analysis of recipient PG, cyclophosphamide (and related metabolites) PK, and T cell profiling was performed. Results: Ten pts who underwent allo HCT were evaluated. This included 6 haplo, 2 MRD, and 2 MUD recipients. All pts received NMA conditioning with fludarabine, cyclophosphamide and irradiation. Four pts developed aGVHD, 1 pt grade I (MUD), 2 pts grade II (haplo), and 1 pt grade III (haplo). Two pts died on study from relapsed disease, 1 pt was taken off study after 6 mos with relapsed disease, 7 pts are alive, 5 of whom completed 2 years of follow up. Successful PG analysis was completed in 9 pts. PK assessments were completed in 10 pts with wide interpatient variability, Table 1 summarizes the median and Cmax range for each measured Cy metabolite. Pts with aGVHD had similar mean Cy metabolite Cmax compared to pts who did not develop aGVHD (Table 1). IP profiling in 10 pts showed relative T cell subset distribution (% PBMC) first peaked at day +5 (34.4±9.9%), with mainly T effector subsets and Treg detected, and nadired at 1 mo (10.8±7.5%) with an overrepresentation of central T memory cells followed by a rebound at 2 mo (34.6±16.7%) driven by CD8 effector & effector memory cells. The 4 pts with aGVHD trended towards higher TEff:Treg ratio at day +5 (2±0.6 vs 3.9±1.5); a trend also observed in the transplanted product (20.6±2.4vs 12±1.8). Conclusion: Our results show the feasibility of assessing PK, PG, and IP in pts receiving PTCy. Early IP of both pts and transplanted product may pinpoint immune imbalance associated with aGHVD later masked during immune reconstitution. Study of a large number of additional pts may clarify the association between early IP and Cy metabolites concentrations with immune profile and with risk of aGVHD. Candidate single nucleotide polymorphisms will be used to evaluate the association of pharmacogenetics with Cy PK, IP, and clinical outcomes. We hope these data will help guide individualized dosing of PTCy to improve effectiveness and minimize toxicity. Figure 1View largeDownload PPTFigure 1View largeDownload PPT Close modal

Management of blood transfusion services in low-resource countries.

Enabling universal access to safe blood components should be a key component of every country's national healthcare strategy. This study aimed to assess the current status of infrastructure and resources of blood transfusion services (BTS) in low- and middle-income countries. A cross-sectional survey was designed to gather information on blood donations, components, redistribution, testing resources and quality management systems (QMSs). The survey was distributed to the International Society of Blood Transfusion members between October 2021 and November 2021. A total of 54 respondents from 20 countries responded to the survey. This included hospital-based BTS/blood centres (46%), national blood centres (11%)and national and regional blood services (11%). Voluntary non-remunerated, replacement and paid donors accounted for 94.2%, 84.6% and 21.1% of donations, respectively. Apheresis donation was available in 59.6% of institutions. National/regional criteria for redistribution of blood components were reported by 75.9% of respondents. Blood components incurred payment charges in 81.5% of respondents' institutions, and payments were borne by patients in 50% of them. Testing methods, such as manual (83%), semi-automated (68%) or fully automated (36.2%), were used either alone or in combination. QMSs were reported in 17 institutions, while accreditation and haemovigilance were reported in 12 and 8 countries, respectively. QMS was implemented in most of the countries despite the common use of paid donations and the lack of advanced testing. Efforts to overcome persistent challenges and wider implementation of patient blood management programmes are required.

Human differentiated eosinophils release IL-13 in response to IL-33 stimulation.

ObjectiveEosinophils are hallmarks in allergic type 2 inflammation and are known to release cytotoxic granule proteins that contribute to inflammation. Eosinophils develop in the bone marrow from hematopoietic stem cells and once mature, have a limited lifespan in culture, making them difficult to study ex vivo. IL-33 has increasingly been shown as a key regulator of type 2 inflammation via signaling through its receptor, ST2. The present study was conducted to detail a method of eosinophil differentiation from hematopoietic stem cells and determine the response to IL-33.MethodsCD34+ and CD14+ cells were isolated from donor apheresis cones and differentiated into eosinophils or macrophage controls, respectively. Morphologic, transcriptional and protein analyses were performed to validate this method of eosinophil differentiation. The effect of IL-33 on differentiated eosinophils was assessed using qPCR, immunofluorescence, and multiplex cytokine array.ResultsCD34 differentiated eosinophils appear morphologically similar by H&E and express eosinophil peroxidase (EPX) protein as well as the conventional eosinophil transcripts EPX, CLC, and MBP. In addition, differentiated eosinophils expressed both isoforms of the IL-33 receptor, ST2L and sST2 throughout the differentiation process. Transcript levels of both IL-33 receptors were up-regulated by treatment with IL-33 at earlier timepoints in the differentiation. These cells also expressed IL-4 and IL-13 mRNA which were up-regulated by IL-33 as well. Notably, IL-13 expression was significantly higher with IL-33 treatment compared to media control at every timepoint measured. IL-33 significantly increased cellular secretion of IL-13 protein at most timepoints throughout differentiation. IL-8, LIF, CCL1, CCL5, CCL7, and CCL8 were also significantly secreted after IL-33 stimulation.ConclusionsOur findings suggest that CD34 differentiated eosinophils are morphologically and phenotypically similar to peripheral eosinophils. The release of specific cytokines in direct response to IL-33 may contribute to the pathogenesis of type 2 inflammation and facilitates new avenues for studying eosinophils as effector cells in vitro.

Screening for antibodies to HLA class I in apheresis donors following Covid‐19 or SARS-CoV-2 vaccination

Transfusion of HLA-specific antibodies may play a role in induction of TRALI, the transfusion complication responsible for most transfusion-related deaths. In Oslo, we screen our apheresis donors and defer HLA-immunized donors from donation of plasma-rich blood components. During the second year of the Covid-19 pandemic and following the first months of SARS-CoV-2 vaccination, both the virus itself and the vaccines were suspected of inducing de novo production of antibodies to HLA class I in patients. For the blood center, the possibility of finding HLA-antibodies in an increased number of blood donors has serious implications. We therefore conducted a study to map the extent of de novo HLA-specific antibodies in representative donor groups. 106 apheresis donors were screened for antibodies to HLA class I/II following Covid-19 or vaccination with either mRNA or adenovirus-vector vaccines, and the findings were compared to pre-Covid blood samples from the same donors. In addition, we analyzed pre-Covid samples from 11 HLA-antibody-positive donors of Covid convalescence plasma. Only three established thrombapheresis donors were deferred due to vaccine-induced HLA-antibodies. In short, our findings did not support the hypothesis that SARS-CoV-2 virus or vaccination cause de novo HLA immunization in healthy blood donors. However, some donors with pre-existing antibodies showed increased antibody expression, confirming a general boost of the immune response following infection or vaccination.

Profile of blood donors in a hemotherapy institution in Midwestern Brazil

Objective: To describe the profile of blood donors in a hospital in the Midwest of Brazil with its own blood bank to have a diagnostic view of the establishment and enable the planning of improvements in services. Methods: This is a descriptive, retrospective study with a quantitative approach. A proportional stratified sampling technique was used, with a confidence level of 95% and a margin of error of 5%, to represent and characterize the study population, obtaining a sample of 363 donors. Subsequently, a proportional allocation was performed in the established groups (fit donors, unfit donors, and platelet apheresis donors). Results: The profile of eligible donors in the institution studied was composed of married (55.2%), male (63.7%), aged between 20 and 30 years (40.4%), with O RhD+ blood (46.7%) and A RhD+ (29.6%) more prevalent. Apheresis platelet donors (50%) are single, female (81.3%), and aged between 31 and 40 years (43.8%). As for unfit donors, 94.8% are temporary-unfit donors, married donors (53.2%), female (54.5%), and between 20 and 40 years old (54.6%), with the categories of health condition and lifestyle being the most prevalent reasons for disability. Conclusion: There is a hegemony for replacement and first-time donors, showing the effectiveness of the solidarity policy implemented in the institution, but it shows the low effectiveness in the loyalty of these donors.

Machine learning-based prediction of fainting during blood donations using donor properties and weather data as features

Background and objectivesFainting is a well-known side effect of blood donation. Such adverse experiences can diminish the return rate for further blood donations. Identifying factors associated with fainting could help prevent adverse incidents during blood donation.Materials and methodsData of 85,040 blood donations from whole blood and apheresis donors within four consecutive years were included in this retrospective study. Seven different machine learning models (random forests, artificial neural networks, XGradient Boosting, AdaBoost, logistic regression, K nearest neighbors, and support vector machines) for predicting fainting during blood donation were established. The used features derived from the data obtained from the questionnaire every donor has to fill in before the donation and weather data of the day of the donation.ResultsOne thousand seven hundred fifteen fainting reactions were observed in 228 846 blood donations from 88,003 donors over a study period of 48 months. Similar values for all machine learning algorithms investigated for NPV, PPV, AUC, and F1-score were obtained. In general, NPV was above 0.996, whereas PPV was below 0.03. AUC and F1-score were close to 0.9 for all models. Essential features predicting fainting during blood donation were systolic and diastolic blood pressure and ambient temperature, humidity, and barometric pressure.ConclusionMachine-learning algorithms can establish prediction models of fainting in blood donors. These new tools can reduce adverse reactions during blood donation and improve donor safety and minimize negative associations relating to blood donation.