Human memory T cells with a naive phenotype accumulate with aging and respond to persistent viruses.

The number of naive T cells decreases and susceptibility to new microbial infections increases with age. Here we describe a previously unknown subset of phenotypically naive human CD8(+) T cells that rapidly secreted multiple cytokines in response to persistent viral antigens but differed transcriptionally from memory and effector T cells. The frequency of these CD8(+) T cells, called 'memory T cells with a naive phenotype' (TMNP cells), increased with age and after severe acute infection and inversely correlated with the residual capacity of the immune system to respond to new infections with age. CD8(+) TMNP cells represent a potential new target for the immunotherapy of persistent infections and should be accounted for and subtracted from the naive pool if truly naive T cells are needed to respond to antigens.

Syphilis seroprevalence and incidence in US blood donors from 2020 to 2022.

BACKGROUND: HIV, HBV, and HCV infections for ~60% of the US blood supply are monitored by TTIMS with syphilis added in 2020. STUDY DESIGN AND METHODS: Data were compiled from October 2020 to September 2022. Syphilis prevalence was estimated for allogeneic and directed donors who were consensus positive (CP) and the subset of those with confirmed-active infections (AI). Prevalence and incidence were stratified by demographics for two consecutive 1-year periods, starting October 1, 2020 and for both years combined. Incidence was estimated for repeat donors. Associations between syphilis positivity and other infections were evaluated. RESULTS: Among 14.75 million donations, syphilis prevalence was 28.4/100,000 donations and significantly higher during the second year compared to the first year. Overall, syphilis incidence for the two-year period was 10.8/100,000 person-years. The adjusted odds of a CP infection were 1.18 (95% CI: 1.11, 1.26) times higher in the second year compared to the first, and for AI, 1.22 (95% CI: 1.10, 1.35) times higher in year 2. Highest rates occurred among males, first-time, Black, and younger (ages 18-39) donors, and those in the South US Census region. Syphilis CP donors were 64 (95% CI: 46, 89) times more likely to be HIV CP, and AI donors 77 (95% CI: 52, 114) times more likely to be HIV CP than non-CP donors, when controlling for confounders. SUMMARY/CONCLUSIONS: Syphilis prevalence increased over the study period mirroring national trends reported by CDC and is significantly associated with HIV CP.

End of selection criteria based on sexual orientation: An international symposium on alternatives to donation deferral.

BACKGROUND AND OBJECTIVES: Until recently, gay, bisexual and other men who have sex with men (MSM) were deferred from donating blood for 3-12 months since the last male-to-male sexual contact. This MSM deferral has been discontinued by several high-income countries (HIC) that now perform gender-neutral donor selection. MATERIALS AND METHODS: An international symposium (held on 20-04-2023) gathered experts from seven HICs to (1) discuss how this paradigm shift might affect the mitigation strategies for transfusion-transmitted infections and (2) address the challenges related to gender-neutral donor selection. RESULTS: Most countries employed a similar approach for implementing a gender-neutral donor selection policy: key stakeholders were consulted; the transition was bridged by time-limited deferrals; donor compliance was monitored; and questions or remarks on anal sex and the number and/or type of sexual partners were often added. Many countries have now adopted a gender-neutral approach in which questions on pre- and post-exposure prophylaxis for human immunodeficiency virus (HIV) have been added (or retained, when already in place). Other countries used mitigation strategies, such as plasma quarantine or pathogen reduction technologies for plasma and/or platelets. CONCLUSION: The experience with gender-neutral donor selection has been largely positive among the countries covered herein and seems to be acceptable to stakeholders, donors and staff. The post-implementation surveillance data collected so far appear reassuring with regards to safety, although longer observation periods are necessary. The putative risks associated with HIV antiretrovirals should be further investigated.

Plasma transfusion-transmission of Zika virus in mice and macaques.

BACKGROUND: Zika virus (ZIKV) epidemics with infections in pregnant women are associated with severe neurological disease in newborns. Although an arbovirus, ZIKV is also blood transfusion-transmitted (TT). Greater knowledge of the efficiency of ZIKV TT would aid decisions on testing and pathogen reduction technologies (PRT). STUDY DESIGN AND METHODS: Plasma units from ZIKV RNA-reactive blood donors were used to study infectivity in vitro, in mice, and in macaques. Furthermore, plasma units were subjected to PRT using amotosalen/ultraviolet light A (A/UVA) before transfusion. RESULTS: In vitro infectivity of ZIKV RNA-reactive plasma varied between 100 and 1000 international units (IU) of ZIKV RNA. Immunodeficient mice were more sensitive with as low as 32 IU sufficient to infect 50% of mice. 50-5500 IU of RNA led to TT in macaques using dose escalation of three different RNA-positive, seronegative plasma units. In contrast, RNA-reactive units collected postseroconversion were not infectious in macaques, even at a dose of 9 million IU RNA. After A/UVA PRT, transfusion of plasma containing up to 18 million IU was no longer infectious in vitro and did not result in ZIKV TT in macaques. CONCLUSION: Significant risks of ZIKV TT are likely confined to a relatively short viremic window before seroconversion, and that sensitive nucleic acid amplification testing likely identifies the majority of infectious plasma. PRT was demonstrated to be effective at preventing ZIKV TT. Considering that there is no approved ZIKV vaccine, these data are relevant to mitigate the risk of TT during the future ZIKV outbreaks.

Estimates of SARS-CoV-2 Seroprevalence and Incidence of Primary SARS-CoV-2 Infections Among Blood Donors, by COVID-19 Vaccination Status - United States, April 2021-September 2022.

Changes in testing behaviors and reporting requirements have hampered the ability to estimate the U.S. SARS-CoV-2 incidence (1). Hybrid immunity (immunity derived from both previous infection and vaccination) has been reported to provide better protection than that from infection or vaccination alone (2). To estimate the incidence of infection and the prevalence of infection- or vaccination-induced antibodies (or both), data from a nationwide, longitudinal cohort of blood donors were analyzed. During the second quarter of 2021 (April-June), an estimated 68.4% of persons aged ≥16 years had infection- or vaccination-induced SARS-CoV-2 antibodies, including 47.5% from vaccination alone, 12.0% from infection alone, and 8.9% from both. By the third quarter of 2022 (July-September), 96.4% had SARS-CoV-2 antibodies from previous infection or vaccination, including 22.6% from infection alone and 26.1% from vaccination alone; 47.7% had hybrid immunity. Prevalence of hybrid immunity was lowest among persons aged ≥65 years (36.9%), the group with the highest risk for severe disease if infected, and was highest among those aged 16-29 years (59.6%). Low prevalence of infection-induced and hybrid immunity among older adults reflects the success of public health infection prevention efforts while also highlighting the importance of older adults staying up to date with recommended COVID-19 vaccination, including at least 1 bivalent dose.*,†.

Identification of Anti-Premembrane Antibody as a Serocomplex-Specific Marker To Discriminate Zika, Dengue, and West Nile Virus Infections.

Although transmission of Zika virus (ZIKV) in the Americas has greatly declined since late 2017, recent reports of reduced risks of symptomatic Zika by prior dengue virus (DENV) infection and increased risks of severe dengue disease by previous ZIKV or DENV infection underscore a critical need for serological tests that can discriminate past ZIKV, DENV, and/or other flavivirus infections and improve our understanding of the immune interactions between these viruses and vaccine strategy in endemic regions. As serological tests for ZIKV primarily focus on envelope (E) and nonstructural protein 1 (NS1), antibodies to other ZIKV proteins have not been explored. Here, we employed Western blot analysis using antigens of 6 flaviviruses from 3 serocomplexes to investigate antibody responses following reverse transcription-PCR (RT-PCR)-confirmed ZIKV infection. Panels of 20 primary ZIKV and 20 ZIKV with previous DENV infection recognized E proteins of all 6 flaviviruses and the NS1 protein of ZIKV with some cross-reactivity to DENV. While the primary ZIKV panel recognized only the premembrane (prM) protein of ZIKV, the ZIKV with previous DENV panel recognized both ZIKV and DENV prM proteins. Analysis of antibody responses following 42 DENV and 18 West Nile virus infections revealed similar patterns of recognition by anti-E and anti-NS1 antibodies, whereas both panels recognized the prM protein of the homologous serocomplex but not others. The specificity was further supported by analysis of sequential samples. Together, these findings suggest that anti-prM antibody is a flavivirus serocomplex-specific marker and can be used to delineate current and past flavivirus infections in endemic areas. IMPORTANCE Despite a decline in Zika virus (ZIKV) transmission since late 2017, questions regarding its surveillance, potential reemergence, and interactions with other flaviviruses in regions where it is endemic remain unanswered. Recent studies have reported reduced risks of symptomatic Zika by prior dengue virus (DENV) infection and increased risks of severe dengue disease by previous ZIKV or DENV infection, highlighting a need for better serological tests to discriminate past ZIKV, DENV, and/or other flavivirus infections and improved understanding of the immune interactions and vaccine strategy for these viruses. As most serological tests for ZIKV focused on envelope and nonstructural protein 1, antibodies to other ZIKV proteins, including potentially specific antibodies, remain understudied. We employed Western blot analysis using antigens of 6 flaviviruses to study antibody responses following well-documented ZIKV, DENV, and West Nile virus infections and identified anti-premembrane antibody as a flavivirus serocomplex-specific marker to delineate current and past flavivirus infections in areas where flaviviruses are endemic.

Robust inactivation of Plasmodium falciparum in red blood cell concentrates using amustaline and glutathione pathogen reduction.

BACKGROUND: Plasmodium falciparum is the parasite responsible for most malaria cases globally. The risk of transfusion-transmitted malaria (TTM) is mitigated by donor deferrals and blood screening strategies, which adversely impact blood availability. Previous studies showed robust inactivation of P. falciparum using nucleic acid-targeting pathogen reduction technologies (PRT) for the treatment of plasma and platelet components or whole blood (WB). The efficacy of the amustaline-glutathione (GSH) PRT to inactivate P. falciparum is here evaluated in red blood cells (RBC), as well the impact of PRT on parasite loads, stages, and strains. STUDY DESIGN AND METHODS: RBC units resuspended in AS-1 or AS-5 additive solutions were spiked with ring stage-infected RBC and treated with the amustaline-GSH PRT. Parasite loads and viability were measured in samples at the time of contamination, and after treatment, using serial 10-fold dilutions of the samples in RBC cultures maintained for up to 4 weeks. RESULTS: P. falciparum viability assays allow for the detection of very low levels of parasite. Initial parasite titer was >5.2 log10 /ml in AS-1/5 RBC. No infectious parasites were detected in amustaline-GSH-treated samples after 4 weeks of culture. Amustaline-GSH inactivated high parasite loads regardless of parasite stages and strains. Amustaline readily penetrates the parasite, irreversibly blocks development, and leads to parasite death and expulsion from RBC. DISCUSSION: Amustaline-GSH PRT demonstrated robust efficacy to inactivate malaria parasites in RBC concentrates. This study completes the portfolio of studies demonstrating the efficacy of nucleic acid-targeting PRTs to mitigate TTM risks as previously reported for platelet concentrates, plasma, and WB.

Mitigating the risk of transfusion-transmitted infections with vector-borne agents solely by means of pathogen reduction.

BACKGROUND: This study evaluated whether pathogen reduction technology (PRT) in plasma and platelets using amotosalen/ultraviolet A light (A/UVA) or in red blood cells using amustaline/glutathione (S-303/GSH) may be used as the sole mitigation strategy preventing transfusion-transmitted West Nile (WNV), dengue (DENV), Zika (ZIKV), and chikungunya (CHIKV) viral, and Babesia microti, Trypanosoma cruzi, and Plasmodium parasitic infections. METHODS: Antibody (Ab) status and pathogen loads (copies/mL) were obtained for donations from US blood donors testing nucleic acid (NAT)-positive for WNV, DENV, ZIKV, CHIKV, and B. microti. Infectivity titers derived from pathogen loads were compared to published PRT log10 reduction factors (LRF); LRFs were also reviewed for Plasmodium and T. cruzi. The potential positive impact on donor retention following removal of deferrals from required questioning and testing for WNV, Babesia, Plasmodium, and T. cruzi was estimated for American Red Cross (ARC) donors. RESULTS: A/UVA and S-303/GSH reduced infectivity to levels in accordance with those recognized by FDA as suitable to replace testing for all agents evaluated. If PRT replaced deferrals resulting from health history questions and/or NAT for WNV, Babesia, Plasmodium, and T. cruzi, 27,758 ARC donors could be retained allowing approximately 50,000 additional donations/year based on 1.79 donations/donor for calendar year 2019 (extrapolated to an estimated 125,000 additional donations nationally). CONCLUSION: Pathogen loads in donations from US blood donors demonstrated that robust PRT may provide an opportunity to replace deferrals associated with donor questioning and NAT for vector-borne agents allowing for significant donor retention and likely increased blood availability.

Donor sex, age and ethnicity impact stored red blood cell antioxidant metabolism through mechanisms in part explained by glucose 6-phosphate dehydrogenase levels and activity.

Red blood cell storage in the blood bank promotes the progressive accumulation of metabolic alterations that may ultimately impact the erythrocyte capacity to cope with oxidant stressors. However, the metabolic underpinnings of the capacity of RBCs to resist oxidant stress and the potential impact of donor biology on this phenotype are not known. Within the framework of the REDS-III RBC-Omics study, RBCs from 8,502 healthy blood donors were stored for 42 days and tested for their propensity to hemolyze following oxidant stress. A subset of extreme hemolyzers donated a second unit of blood, which was stored for 10, 23, and 42 days and profiled again for oxidative hemolysis and metabolomics (599 samples). Alterations of RBC energy and redox homeostasis were noted in donors with high oxidative hemolysis. RBCs from females, donors over 60 years old, donors of Asian/South Asian race-ethnicity, and RBCs stored in additive solution-3 were each independently characterized by improved antioxidant metabolism compared to, respectively, males, donors under 30 years old, Hispanic and African American race ethnicity donors, and RBCs stored in additive solution-1. Merging metabolomics data with results from an independent GWAS study on the same cohort, we identified metabolic markers of hemolysis and G6PD-deficiency, which were associated with extremes in oxidative hemolysis and dysregulation in NADPH and glutathione-dependent detoxification pathways of oxidized lipids. Donor sex, age, ethnicity, additive solution and G6PD status impact the metabolism of the stored erythrocyte and its susceptibility to hemolysis following oxidative insults.

Inactivation of yellow fever virus with amotosalen and ultraviolet A light pathogen-reduction technology.

BACKGROUND: The reemergence of yellow fever virus (YFV) in Africa and Brazil, and massive vaccine campaigns triggered to contain the outbreaks, have raised concerns over blood transfusion safety and availability with increased risk of YFV transfusion-transmitted infections (TTIs) by native and vaccine-acquired YFV. Blood donor deferral for 2 to 4 weeks following live attenuated YFV vaccination, and deferral for travel to endemic/epidemic areas, may result in blood donor loss and impact platelet component (PC) stocks. This study investigated the efficacy of INTERCEPT Blood System pathogen reduction (PR) with use of amotosalen and ultraviolet A (UVA) light to inactivate high levels of YFV in PCs. MATERIALS: Four units of apheresis platelets prepared in 35% plasma/65% platelet additive solution (PC-PAS) and 4 units of PC in 100% human plasma (PC-Plasma) were spiked with high infectious titers of YFV (YFV-17D vaccine strain). YFV-17D infectious titers were measured by plaque assay and expressed as plaque-forming units (PFU) before and after amotosalen/UVA treatment to determine log reduction. RESULTS: The mean YFV-17D infectious titers in PC before inactivation were 5.5 ± 0.1 log PFU/mL in PC-PAS and 5.3 ± 0.1 log PFU/mL in PC-Plasma. No infectivity was detected immediately after amotosalen/UVA treatment. CONCLUSION: The amotosalen/UVA PR system inactivated high titers of infectious YFV-17D in PC. This PR technology could reduce the risk of YFV TTI and help secure PC supplies in areas experiencing YFV outbreaks where massive vaccination campaigns are required.

Inactivation of Plasmodium falciparum in whole blood using the amustaline and glutathione pathogen reduction technology.

BACKGROUND: Risk of transfusion-transmitted (TT) malaria is mainly associated with whole blood (WB) or red blood cell (RBC) transfusion. Risk mitigation relies mostly on donor deferral while a limited number of countries perform blood testing, both negatively impacting blood availability. This study investigated the efficacy of the pathogen reduction system using amustaline and glutathione (GSH) to inactivate Plasmodium falciparum in WB. STUDY DESIGN AND METHODS: WB units were spiked with ring stage P. falciparum infected RBCs. Parasite loads were measured in samples at time of infection, after 24 hours at room temperature (RT), and after a 24-hour incubation at RT post-treatment with 0.2 mM amustaline and 2 mM GSH. Serial 10-fold dilutions of the samples were inoculated to RBC cultures and maintained up to 4 weeks. Parasitemia was quantified by cytometry. RESULTS: The P. falciparum viability assay has a limit of detection of a single live parasite per sample. Input parasite titer was >5.7 log10 TCID50 per mL. A 24-hour incubation at RT paused parasite development in controls, but they retained viability and infectivity when tested in culture. In contrast, no infectious parasites were detected in the amustaline/GSH-treated sample after 4 weeks of culture. CONCLUSION: A robust level of P. falciparum inactivation was achieved in WB using amustaline/GSH treatment. Parasite log reduction was >5.7 log10 TCID50 per mL. Development of such a pathogen reduction system may provide an opportunity to reduce the risk of TT malaria and improve blood availability.

Inactivation of a broad spectrum of viruses and parasites by photochemical treatment of plasma and platelets using amotosalen and ultraviolet A light.

BACKGROUND: The INTERCEPT Blood System pathogen reduction technology (PRT), which uses amotosalen and ultraviolet A light treatment (amotosalen/UV-PRT), inactivates pathogens in plasma and platelet components (PCs). This review summarizes data describing the inactivation efficacy of amotosalen/UVA-PRT for a broad spectrum of viruses and parasites. METHODS: Twenty-five enveloped viruses, six nonenveloped viruses (NEVs), and four parasites species were evaluated for sensitivity to amotosalen/UVA-PRT. Pathogens were spiked into plasma and PC at high titers. Samples were collected before and after PRT and assessed for infectivity with cell cultures or animal models. Log reduction factors (LRFs) were defined as the difference in infectious titers before and after amotosalen/UV-PRT. RESULTS: LRFs of ≥4.0 log were reported for 19 pathogens in plasma (range, ≥4.0 to ≥7.6), 28 pathogens in PC in platelet additive solution (PC-PAS; ≥4.1-≥7.8), and 14 pathogens in PC in 100% plasma (PC-100%; (≥4.3->8.4). Twenty-five enveloped viruses and two NEVs were sensitive to amotosalen/UV-PRT; LRF ranged from >2.9 to ≥7.6 in plasma, 2.4 or greater to greater than 6.9 in PC-PAS and >3.5 to >6.5 in PC-100%. Infectious titers for four parasites were reduced by >4.0 log in all PC and plasma (≥4.9 to >8.4). CONCLUSION: Amotosalen/UVA-PRT demonstrated effective infectious titer reduction for a broad spectrum of viruses and parasites. This confirms the capacity of this system to reduce the risk of viral and parasitic transfusion-transmitted infections by plasma and PCs in various geographies.

Sepsis from an apheresis platelet contaminated with Acinetobacter calcoaceticus/baumannii complex bacteria and Staphylococcus saprophyticus after pathogen reduction.

BACKGROUND: Strategies to reduce platelet (PLT) bacterial contamination include donor screening, skin disinfection, sample diversion, bacterial culture, pathogen reduction (PR), and day-of-transfusion tests. We report bacterial sepsis following a pathogen-reduced PLT transfusion. CASE REPORT: An adult male with relapsed acute lymphoblastic leukemia was successfully treated for central catheter-associated Staphylococcus aureus bacteremia. A peripherally inserted central catheter (PICC) was placed. Chills, rigors, and flushing developed immediately after PICC-infused pathogen-reduced PLTs, progressing to septic shock requiring intensive care management. METHODS: PICC and peripheral blood (PB), transfused bag saline flushes (TBFs), environmental samples, and the pathogen-reduced untransfused co-component (CC) were cultured. Plasma metagenomic and bacterial isolate whole-genome sequencing; PLT mitochondrial DNA (mtDNA) testing of untransfused CC and TBF; CC testing for amotosalen (S-59)/S-59 photoproducts; isolate PR studies (INTERCEPT); and TBF polymerase chain reaction for recipient Y-chromosome DNA were performed. RESULTS: PB and PICC cultures grew Acinetobacter calcoaceticus/baumannii complex (ACBC). TBF was gram-positive; mass spectrometry identified ACBC and Staphylococcus saprophyticus (SS). CC Gram stain and cultures were negative. Environmental cultures, some done after decontamination, were ACBC/SS negative. Posttransfusion patient plasma and TBF ACBC sequences were genetically identical. No Y-chromosome signal was detected in TBF. S-59 photoproducts and evidence of mtDNA amplification inhibition were found in the CC. Spiking PR studies showed >5.9-log inactivation for both isolates. Donor skin cultures for Acinetobacter were negative. CONCLUSION: CC sterility, PR studies, residual S-59 photoproducts, and mtDNA amplification inhibition suggest successful PR. Unidentified environmental sources and inherent or acquired bag defects may have contributed to postmanufacturing pathogen-reduced PLT contamination.

Zika virus preferentially replicates in the female reproductive tract after vaginal inoculation of rhesus macaques.

Zika virus (ZIKV) is a mosquito-transmitted virus that can cause severe defects in an infected fetus. ZIKV is also transmitted by sexual contact, although the relative importance of sexual transmission is unclear. To better understand the role of sexual transmission in ZIKV pathogenesis, a nonhuman primate (NHP) model of vaginal transmission was developed. ZIKV was readily transmitted to mature cycling female rhesus macaque (RM) by vaginal inoculation with 104-106 plaque-forming units (PFU). However, there was variability in susceptibility between the individual RM with 1->8 vaginal inoculations required to establish infection. After treatment with Depoprovera, a widely used contraceptive progestin, two RM that initially resisted 8 vaginal ZIKV inoculations became infected after one ZIKV inoculation. Thus, Depoprovera seemed to enhance susceptibility to vaginal ZIKV transmission. Unexpectedly, the kinetics of virus replication and dissemination after intravaginal ZIKV inoculation were markedly different from RM infected with ZIKV by subcutaneous (SQ) virus inoculation. Several groups have reported that after SQ ZIKV inoculation vRNA is rapidly detected in blood plasma with vRNA less common in urine and saliva and only rarely detected in female reproductive tract (FRT) secretions. In contrast, in vaginally inoculated RM, plasma vRNA is delayed for several days and ZIKV replication in, and vRNA shedding from, the FRT was found in all 6 animals. Further, after intravaginal transmission ZIKV RNA shedding from FRT secretions was detected before or simultaneously with plasma vRNA, and persisted for at least as long. Thus, ZIKV replication in the FRT was independent of, and often preceded virus replication in the tissues contributing to plasma vRNA. These results support the conclusion that ZIKV preferentially replicates in the FRT after vaginal transmission, but not after SQ transmission, and raise the possibility that there is enhanced fetal infection and pathology after vaginal ZIKV transmission compared to a mosquito transmitted ZIKV.

Blood, sweat, and tears: Red Blood Cell-Omics study objectives, design, and recruitment activities.

BACKGROUND: The Red Blood Cell (RBC)-Omics study was initiated to build a large data set containing behavioral, genetic, and biochemical characteristics of blood donors with linkage to outcomes of the patients transfused with their donated RBCs. STUDY DESIGN AND METHODS: The cohort was recruited from four US blood centers. Demographic and donation data were obtained from center records. A questionnaire to assess pica, restless leg syndrome, iron supplementation, hormone use, and menstrual and pregnancy history was completed at enrollment. Blood was obtained for a complete blood count, DNA, and ferritin testing. A leukocyte-reduced RBC sample was transferred to a custom storage bag for hemolysis testing at Storage Days 39 to 42. A subset was recalled to evaluate the kinetics and stability of hemolysis measures. RESULTS: A total of 13,403 racially/ethnically diverse (12% African American, 12% Asian, 8% Hispanic, 64% white, and 5% multiracial/other) donors of both sexes were enrolled and ranged from 18 to 90 years of age; 15% were high-intensity donors (nine or more donations in the prior 24 mo without low hemoglobin deferral). Data elements are available for 97% to 99% of the cohort. CONCLUSIONS: The cohort provides demographic, behavioral, biochemical, and genetic data for a broad range of blood donor studies related to iron metabolism, adverse consequences of iron deficiency, and differential hemolysis (including oxidative and osmotic stress perturbations) during RBC storage. Linkage to recipient outcomes may permit analysis of how donor characteristics affect transfusion efficacy. Repository DNA, plasma, and RBC samples should expand the usefulness of the current data set.

Frequent blood donations alter susceptibility of red blood cells to storage- and stress-induced hemolysis.

BACKGROUND: Frequent whole blood donations increase the prevalence of iron depletion in blood donors, which may subsequently interfere with normal erythropoiesis. The purpose of this study was to evaluate the associations between donation frequency and red blood cell (RBC) storage stability in a racially/ethnically diverse population of blood donors. STUDY DESIGN: Leukoreduced RBC concentrate-derived samples from 13,403 donors were stored for 39 to 42 days (1-6°C) and then evaluated for storage, osmotic, and oxidative hemolysis. Iron status was evaluated by plasma ferritin measurement and self-reported intake of iron supplements. Donation history in the prior 2 years was obtained for each subject. RESULTS: Frequent blood donors enrolled in this study were likely to be white, male, and of older age (56.1 ± 5.0 years). Prior donation intensity was negatively associated with oxidative hemolysis (p < 0.0001) in multivariate analyses correcting for age, sex, and race/ethnicity. Increased plasma ferritin concentration was associated with increased RBC susceptibility to each of the three measures of hemolysis (p < 0.0001 for all), whereas self-reported iron intake was associated with reduced susceptibility to osmotic and oxidative hemolysis (p < 0.0001 for both). CONCLUSIONS: Frequent blood donations may alter the quality of blood components by modulating RBC predisposition to hemolysis. RBCs collected from frequent donors with low ferritin have altered susceptibility to hemolysis. Thus, frequent donation and associated iron loss may alter the quality of stored RBC components collected from iron-deficient donors. Further investigation is necessary to assess posttransfusion safety and efficacy in patients receiving these RBC products.

Heterogeneity of blood processing and storage additives in different centers impacts stored red blood cell metabolism as much as storage time: lessons from REDS-III-Omics.

BACKGROUND: Biological and technical variability has been increasingly appreciated as a key factor impacting red blood cell (RBC) storability and, potentially, transfusion outcomes. Here, we performed metabolomics analyses to investigate the impact of factors other than storage duration on the metabolic phenotypes of stored RBC in a multicenter study. STUDY DESIGN AND METHODS: Within the framework of the REDS-III (Recipient Epidemiology and Donor Evaluation Study-III) RBC-Omics study, 13,403 donors were enrolled from four blood centers across the United States and tested for the propensity of their RBCs to hemolyze after 42 days of storage. Extreme hemolyzers were recalled and donated a second unit of blood. Units were stored for 10, 23, and 42 days prior to sample acquisition for metabolomics analyses. RESULTS: Unsupervised analyses of metabolomics data from 599 selected samples revealed a strong impact (14.2% of variance) of storage duration on metabolic phenotypes of RBCs. The blood center collecting and processing the units explained an additional 12.2% of the total variance, a difference primarily attributable to the storage additive (additive solution 1 vs. additive solution 3) used in the different hubs. Samples stored in mannitol-free/citrate-loaded AS-3 were characterized by elevated levels of high-energy compounds, improved glycolysis, and glutathione homeostasis. Increased methionine metabolism and activation of the transsulfuration pathway was noted in samples processed in the center using additive solution 1. CONCLUSION: Blood processing impacts the metabolic heterogeneity of stored RBCs from the largest multicenter metabolomics study in transfusion medicine to date. Studies are needed to understand if these metabolic differences influenced by processing/storage strategies impact the effectiveness of transfusions clinically.

Intradonor reproducibility and changes in hemolytic variables during red blood cell storage: results of recall phase of the REDS-III RBC-Omics study.

BACKGROUND: Genetic determinants may underlie the susceptibility of red blood cells (RBCs) to hemolyze in vivo and during routine storage. This study characterized the reproducibility and dynamics of in vitro hemolysis variables from a subset of the 13,403 blood donors enrolled in the RBC-Omics study. STUDY DESIGN AND METHODS: RBC-Omics donors with either low or high hemolysis results on 4°C-stored leukoreduced (LR)-RBC samples from enrollment donations stored for 39 to 42 days were recalled 2 to 12 months later to donate LR-RBCs. Samples of stored LR-RBCs from the unit and from transfer bags were evaluated for spontaneous and stress-induced hemolysis at selected storage time points. Intradonor reproducibility of hemolysis variables was evaluated in transfer bags over two donations. Hemolysis data at serial storage time points were generated on LR-RBCs from parent bags and analyzed by site, sex, race/ethnicity, and donation frequency. RESULTS: A total of 664 donors were successfully recalled. Analysis of intradonor reproducibility revealed that osmotic and oxidative hemolysis demonstrated good and moderate reproducibility (Pearson's r = 0.85 and r = 0.53, respectively), while spontaneous hemolysis reproducibility was poor (r = 0.40). Longitudinal hemolysis in parent bags showed large increases over time in spontaneous (508.6%) and oxidative hemolysis (399.8%) and smaller increases in osmotic (9.4%) and mechanical fragility (3.4%; all p < 0.0001). CONCLUSION: Spontaneous hemolysis is poorly reproducible in donors over time and may depend on site processing methods, while oxidative and osmotic hemolysis were reproducible in donors and hence could reflect consistent heritable phenotypes attributable to genetic traits. Spontaneous and oxidative hemolysis increased over time of storage, whereas osmotic and mechanical hemolysis remained relatively stable.

Piloting and implementation of quality assessment and quality control procedures in RBC-Omics: a large multi-center study of red blood cell hemolysis during storage.

BACKGROUND: The major aims of the RBC-Omics study were to evaluate the genomic and metabolomic determinants of spontaneous and stress-induced hemolysis during RBC storage. This study was unique in scale and design to allow evaluation of RBC donations from a sufficient number of donors across the spectrum of race, ethnicity, sex, and donation intensity. Study procedures were carefully piloted, optimized, and controlled to enable high-quality data collection. METHODS: The enrollment goal of 14,000 RBC donors across four centers, with characterization of RBC hemolysis across two testing laboratories, required rigorous piloting and optimization and establishment of a quality assurance (QA) and quality control (QC) program. Optimization of WBC elution from leukoreduction (LR) filters, development and validation of small-volume transfer bags, impact of manufacturing and sample-handling procedures on hemolysis parameters, and testing consistency across laboratories and technicians and over time were part of this quality assurance/quality control program. RESULTS: LR filter elution procedures were optimized for obtaining DNA for analysis. Significant differences between standard and pediatric storage bags led to use of an alternative LR-RBC transfer bag. The impact of sample preparation and freezing methods on metabolomics analyses was evaluated. Proficiency testing monitored and documented testing consistency across laboratories and technicians. CONCLUSION: Piloting and optimization, and establishment of a robust quality assurance/quality control program documented process consistency throughout the study and was essential in executing this large-scale multicenter study. This program supports the validity of the RBC-Omics study results and a sample repository that can be used in future studies.

In vitro evaluation of pathogen inactivated platelet quality: An 8 year experience of routine use in Galicia, Spain.

BACKGROUND: Platelet concentrates (PCs) treated by the pathogen inactivation technology (PI) using amotosalen and UVA illumination (PI-PCs) can be manufactured in additive solutions (PAS-III and PAS-IIIM) or in 100% Plasma. Quality control (QC) is an integral part of the production. We capitalized on our ongoing QC program to capture 8 years-worth of data on parameters related to the quality of 116,214 PI-PCs produced under different manufacturing methods. MATERIALS AND METHODS: Selected in vitro parameters of metabolism, activation, and storage were analyzed for the different manufacturing periods to compare PI-PCs versus conventional PCs (C-PCs) resuspended in different PAS. RESULTS AND DISCUSSION: All BC-PCs met quality standards for pH and dose and residual leucocytes. As expected, storage time correlated with increased lactate, LDH, Annexin V, CD62, sCD40 L levels and decreased glucose and pH. With PAS-IIIM, higher levels of glucose were observed toward the end of shelf life (p < 0.0001) with lower platelet activation markers Annexin V (p = 0.038) and CD62 (p = 0.0006). Following PI implementation, a low expire rate of <0.5% was observed. While a 2.3% mean increase in the production of PCs occurred from 2011 to 2015, the distribution of red blood cell concentrates dropped by 4.4%. A mean incidence of 0.14% for transfusion-related adverse reaction was observed while PI-PCs were distributed, similar to the one observed with C-PCs. Overall, PI-PCs prepared in additive solutions consistently met quality standards. Those prepared in PAS-IIIM appeared to have better retention of in vitro characteristics compared to PAS-III though all demonstrated functionality and clinical effectiveness.