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Islet cell transplantation has therapeutic potential to cure type 1 diabetes (T1D), which is characterized by autoimmune-mediated destruction of insulin-producing β cells. However, current success rates are limited by long-term decline in islet graft function resulting partially from poor revascularization and immune destruction. Mesenchymal stem cells (MSCs) have the potential to enhance islet transplantation and prevent disease progression by a multifaceted approach. MSCs have been shown to be effective at inhibiting inflammatory-mediated immune responses and at promoting tissue regeneration. The immunomodulatory and tissue repairing properties of MSCs may benefit β cell regeneration in the context of T1D. This review will elucidate how MSCs can minimize β cell damage by providing survival signals and simultaneously modulate the immune response by inhibiting activation, and proliferation of several immune cell types. In addition, MSCs can enhance islet graft revascularization, maintaining long-term β cell viability and function. [ABSTRACT FROM AUTHOR]

Background and Aim: An essential aspect of ensuring availability and stability of mesenchymal stem/stromal cells (MSCs) products for clinical use is that these cells are cryopreserved before individual infusion into patients. Currently, cryopreservation of MSCs involves use of a cryoprotectant solution containing dimethyl sulfoxide (DMSO). However, it is recognized that DMSO may be toxic for both the patient and the MSC product. In this Production Assistance for Cellular Therapies (PACT) and Biomedical Excellence for Safer Transfusion (BEST) Collaborative study, we compared a novel DMSO-free solution with DMSO containing cryoprotectant solutions for freezing MSCs., Methods: A DMSO-free cryoprotectant solution containing sucrose, glycerol, and isoleucine (SGI) in a base of Plasmalyte A was prepared at the University of Minnesota. Cryoprotectant solutions containing 5-10% DMSO (in-house) were prepared at seven participating centers (five from USA, one each from Australia and Germany). The MSCs were isolated from bone marrow or adipose tissue and cultured ex vivo per local protocols at each center. The cells in suspension were frozen by aliquoting into vials/bags. For six out of the seven centers, the vials/bags were placed in a controlled rate freezer (one center placed them at -80°C freezer overnight) before transferring to liquid nitrogen. The cells were kept frozen for at least one week before thawing and testing. Pre- and post-thaw assessment included cell viability and recovery, immunophenotype as well as transcriptional and gene expression profiles. Linear regression, mixed effects models and two-sided t-tests were applied for statistical analysis., Results: MSCs had an average viability of 94.3% (95% CI: 87.2-100%) before cryopreservation, decreasing by 4.5% (95% CI: 0.03-9.0%; P: 0.049) and 11.4% (95% CI: 6.9-15.8%; P< 0.001), for MSCs cryopreserved in the in-house and SGI solutions, respectively. The average recovery of viable MSCs cryopreserved in the SGI was 92.9% (95% CI: 85.7-100.0%), and it was lower by 5.6% (95% CI: 1.3-9.8%, P < 0.013) for the in-house solution. Additionally, MSCs cryopreserved in the two solutions had expected level of expressions for CD45, CD73, CD90, and CD105 with no significant difference in global gene expression profiles., Conclusion: MSCs cryopreserved in a DMSO-free solution containing sucrose, glycerol, and isoleucine in a base of Plasmalyte A had slightly lower cell viability, better recovery, and comparable immunophenotype and global gene expression profiles compared to MSCs cryopreserved in DMSO containing solutions. The average viability of MSCs in the novel solution was above 80% and, thus, likely clinically acceptable. Future studies are suggested to test the post-thaw functions of MSCs cryopreserved in the novel DMSO-free solution., Competing Interests: Declaration of competing interest AH is the Founder and Chief Scientific Officer of Evia Bio, a company that was established after the current study was completed and is commercializing the proprietary SGI solution used in this study., (Copyright © 2024 International Society for Cell & Gene Therapy. Published by Elsevier Inc. All rights reserved.)

Background Aims: Culture-derived mesenchymal stromal cells (MSCs) exhibit variable characteristics when manufactured using different methods, source material and culture media. The purpose of this multicenter study was to assess the impact on MSC expansion, gene expression and other characteristics when different laboratories expanded MSCs from cultures initiated with bone marrow-MSC aliquots derived from the same donor source material yet with different growth media., Methods: Eight centers expanded MSCs using four human platelet lysate (HPL) and one fetal bovine serum (FBS) products as media supplements. The expanded cells were taken through two passages then assessed for cell count, viability, doubling time, immunophenotype, cell function, immunosuppression and gene expression. Results were analyzed by growth media and by center., Results: Center methodologies varied by their local seeding density, feeding regimen, inoculation density, base media and other growth media features (antibiotics, glutamine, serum). Doubling times were more dependent on center than on media supplements. Two centers had appropriate immunophenotyping showing all MSC cultures were positive for CD105, CD73, CD90 and negative for CD34, CD45, CD14, HLA-DR. MSCs cultured in media supplemented with FBS compared with HPL featured greater T-cell inhibition potential. Gene expression analysis showed greater impact of the type of media supplement (HPL versus FBS) than the manufacturing center. Specifically, nine genes were decreased in expression and six increased when combining the four HPL-grown MSCs versus FBS (false discovery rate [FDR] <0.01), however, without significant difference between different sources of HPL (FDR <0.01)., Conclusions: Local manufacturing process plays a critical role in MSC expansion while growth media may influence function and gene expression. All HPL and FBS products supported cell growth., Competing Interests: Declaration of Competing Interest The authors have no commercial, proprietary, or financial interest in the products or companies described in this article., (Copyright © 2023 International Society for Cell & Gene Therapy. Published by Elsevier Inc. All rights reserved.)

Abstract: Glycophorin A (GPA), a red blood cell (RBC) surface glycoprotein, can maintain peripheral blood leukocyte quiescence through interaction with a sialic acid-binding Ig-like lectin (Siglec-9). Under inflammatory conditions such as sickle cell disease (SCD), the GPA of RBCs undergo structural changes that affect this interaction. Peripheral blood samples from patients with SCD before and after RBC transfusions were probed for neutrophil and monocyte activation markers and analyzed by fluorescence-activated cell sorting (FACS). RBCs were purified and tested by FACS for Siglec-9 binding and GPA expression, and incubated with cultured endothelial cells to evaluate their effect on barrier function. Activated leukocytes from healthy subjects (HS) were coincubated with healthy RBCs (RBCH), GPA-altered RBCs, or GPA-overexpressing (OE) cells and analyzed using FACS. Monocyte CD63 and neutrophil CD66b from patients with SCD at baseline were increased 47% and 27%, respectively, as compared with HS (P = .0017, P = .0162). After transfusion, these markers were suppressed by 22% and 17% (P = .0084, P = .0633). GPA expression in RBCSCD was 38% higher (P = .0291) with decreased Siglec-9 binding compared with RBCH (0.0266). Monocyte CD63 and neutrophil CD66b were suppressed after incubation with RBCH and GPA-OE cells, but not with GPA-altered RBCs. Endothelial barrier dysfunction after lipopolysaccharide challenge was restored fully with exposure to RBCH, but not with RBCSCD, from patients in pain crisis, or with RBCH with altered GPA. Pretransfusion RBCSCD do not effectively maintain the quiescence of leukocytes and endothelium, but quiescence is restored through RBC transfusion, likely by reestablished GPA-Siglec-9 interactions., (© 2024 by The American Society of Hematology. Licensed under Creative Commons Attribution-NonCommercial-NoDerivatives 4.0 International (CC BY-NC-ND 4.0), permitting only noncommercial, nonderivative use with attribution. All other rights reserved.)

Background: The success of allogeneic hematopoietic stem cell transplantation is dependent on a world-wide network of collection centers providing donations that predominantly have been infused as fresh cells. The logistics chain that supports the just-in-time delivery model for stem cell and immunotherapy products was severely stressed by the COVID pandemic, and in early 2020 a number of national and international bodies recommended that cells should be cryopreserved at the collection or transplant center to avoid interruptions in their acquisition or delivery to patients who had started conditioning., Study Design: To assess the potential consequences of such pandemic-related deviations to normal practice, we surveyed nine international laboratories to determine if the characteristics or transplant outcomes of allogeneic stem cell donations differed in the immediate periods before and after the switch to routine cryopreservation., Results: Nine centers on two continents provided data for 72 HSC donations just before, and 71 just after, switching to cryopreservation for allogeneic HSC products. No statistically significant differences between the period before and after cryopreservation were noted for time from product collection to receipt, product temperature at receipt, or CD34 + cell viability at receipt. There was an indication of slower absolute neutrophil count recovery after cryopreservation was required (mean time of 15 vs. 17.6 days)., Discussion: While there were no apparent changes to most parameters studied, there was an indication of slower neutrophil engraftment that will need to be examined in larger, longer term studies., (© 2023 AABB.)

Despite the low risk of peripherally inserted central catheter (PICC) insertion-related bleeding, the practice of administering prophylactic platelets varies greatly. Limiting unnecessary blood product transfusions reduces transfusion-related adverse events, financial cost, and delays in care. We assessed the impact of lowering prophylactic platelet administration threshold on blood product utilization patterns and bleeding events. This quasi-experimental study was conducted in an urban academic tertiary medical center. The study population included patients with platelet counts ≥ 10,000/µL and < 50,000/µL undergoing PICC placement in 2018 and 2019 when the minimum platelet thresholds were 50,000/µL and 10,000/µL, respectively. The primary outcome was blood product utilization and the secondary outcome was PICC insertion-related bleeding complications. Thirty-five patients using the 10,000/µL (10 K) platelet threshold and 46 patients using the 50,000/µL (50 K) platelet threshold were enrolled. The 50 K group received more platelets before PICC insertion (0.870 ± 0.885 and 0.143 ± 0.430 pools of platelets-per-person, p < 0.001). No patients experienced clinically significant bleeding. Immediately following PICC insertion, minor bleeding occurred in five patients (two [4.3%] and three [8.6%] in the 50 K and 10 K groups, respectively). Bleeding rates between the two cohorts did not differ (p = 0.647). Lowering the minimum platelet threshold from 50,000/µL to 10,000/µL resulted in less prophylactic platelet and total blood product administration with no appreciable difference in PICC insertion-related bleeding., (© 2022. This is a U.S. Government work and not under copyright protection in the US; foreign copyright protection may apply.)

Background: The IL-3-pSTAT5 assay, a new, rapid, and standardized flow-cytometry-based assay may compensate for several limitations of the colony-forming unit (CFU) assay typically used for stem cell potency assessments of cord blood units (CBU). We performed an inter-laboratory evaluation of the performance of this new assay., Study Design and Methods: This Biomedical Excellence for Safer Transfusion (BEST) Collaborative multicenter, international study included 15 participants from public cord blood banks (CBBs), CBB-supporting research laboratories, and stem cell laboratories. To perform the IL-3-pSTAT5 assay, participating centers received reagents, instructions, and 10 blind CBU samples, including eight normal samples and two samples exposed to a transient warming event. We measured inter-laboratory agreement qualitatively (proportion of correctly classified samples) and quantitatively (coefficient of variation [CV], correlation coefficients, receiver operating characteristics (ROC) curve, and intraclass correlation coefficient [ICC])., Results: The qualitative agreement was 97.3% (i.e., 107/110; Fleiss' kappa = 0.835). The average CV on a per-sample basis was 11.57% among all samples, 8.99% among normal samples, and on a per-center basis was 9.42% among normal samples. In a correlation matrix that compared results across centers, the mean Pearson's correlation coefficient was 0.88 (standard deviation = 0.04). The ICC was 0.83 (95% confidence interval = 0.68-0.95). The area under the curve (AUC) from the ROC curve was 0.9974., Discussion: Excellent qualitative and quantitative agreement was exhibited across laboratories. The IL-3-pSTAT5 assay may therefore be implemented in flow cytometry laboratories to rapidly and reliably provide standardized measures of stem cell potency in CBUs., (© 2022 AABB.)

Background: At the start of the coronavirus disease 2019 (COVID-19) pandemic, widespread blood shortages were anticipated. We sought to determine how hospital blood supply and blood utilization were affected by the first wave of COVID-19., Study Design and Methods: Weekly red blood cell (RBC) and platelet (PLT) inventory, transfusion, and outdate data were collected from 13 institutions in the United States, Brazil, Canada, and Denmark from March 1st to December 31st of 2020 and 2019. Data from the sites were aligned based on each site's local first peak of COVID-19 cases, and data from 2020 (pandemic year) were compared with data from the corresponding period in 2019 (pre-pandemic baseline)., Results: RBC inventories were 3% lower in 2020 than in 2019 (680 vs. 704, p < .001) and 5% fewer RBCs were transfused per week compared to 2019 (477 vs. 501, p < .001). However, during the first COVID-19 peak, RBC and PLT inventories were higher than normal, as reflected by deviation from par, days on hand, and percent outdated. At this time, 16% fewer inpatient beds were occupied, and 43% fewer surgeries were performed compared to 2019 (p < .001). In contrast to 2019 when there was no correlation, there was, in 2020, significant negative correlations between RBC and PLT days on hand and both percentage occupancy of inpatient beds and percentage of surgeries performed., Conclusion: During the COVID-19 pandemic in 2020, RBC and PLT inventories remained adequate. During the first wave of cases, significant decreases in patient care activities were associated with excess RBC and PLT supplies and increased product outdating., (© 2022 AABB.)

Aims: While the SARS-CoV-2 pandemic may be contained through vaccination, transfusion of convalescent plasma (CCP) from individuals who recovered from COVID-19 (CCP) is considered an alternative treatment. We investigate if CCP transfusion in patients with severe respiratory failure increases plasma titres of SARS-CoV-2 antibodies and improves clinical outcomes., Methods: Patients with COVID-19 (n=34) were consented for CCP transfusion and serial blood draws pretransfusion and post-transfusion. Plasma SARS-CoV-2 antireceptor binding domain (RBD) IgG and IgM titres were measured by ELISA serially, and compared with serial plasma titre levels from control patients (n=68). The primary outcome was survival at 30 days, and secondary outcomes were length of ventilator and/or extracorporeal membrane oxygenation (ECMO) support, length of stay (LOS) in the hospital and in the intensive care unit (ICU). Outcomes were compared with matched control patients (n=34). Kinetics of antibodies and clinical outcomes were compared using LOess regression and ORs, respectively., Results: Prior to CCP transfusion, 74% of patients were anti-RBD seropositive for IgG (median 1:3200), and 81% were anti-RBD IgM seropositive (median 1:320), while 16% were seronegative. The kinetics of antibody titres in CCP recipients were similar to controls. CCP recipients presented with similar survival, duration on ventilatory and/or ECMO support, as well as ICU and hospital LOS compared with controls., Conclusions: CCP transfusion did not increase the kinetics of SARS-CoV2 antibodies and did not result in improved clinical outcomes in patients with COVID-19 with severe respiratory failure, suggesting that CCP may not be indicated in this category of patients., Competing Interests: Competing interests: None declared., (© Author(s) (or their employer(s)) 2022. Re-use permitted under CC BY-NC. No commercial re-use. See rights and permissions. Published by BMJ.)

Background: Both M and N alleles encode antigens on Glycophorin A (GPA), a red blood cell (RBC) surface sialoglycoprotein. Interaction between RBC GPA and leukocyte surface lectins may downregulate their activation. The current study investigates if RBC autoantibodies against GPA, such as auto-anti-M/N, prime an activated phenotype in peripheral blood leukocytes., Methods: Leukocyte activation was assessed in whole blood from patients with auto-anti-GPA (anti-M/N) and compared to those with allo-anti-M/N and healthy subjects. Control samples from healthy subjects with no antibodies incubated in vitro with either anti-GPA or anti-Rh were analyzed for neutrophil and monocyte surface activation marker expression, reactive oxygen species (ROS) content, and formation of aggregates with RBCs. Samples incubated with an IgG 1 isotype antibody served as controls., Results: Ex vivo, neutrophil CD66b and monocyte CD63 surface expression was increased in patients with auto-anti-M/N compared to those with allo anti-M/N (p = .1757; p = .0698) and to healthy subjects (p = .0186; p = .013). In vitro, neutrophil CD66b and monocyte CD63 surface expression was increased following incubation with anti-GPA compared to anti-Rh (p = .0003; p = .0328) and isotype control (p = .000; p = .0062). Intracellular ROS content increased in both neutrophils and monocytes incubated with anti-GPA compared to anti-Rh (p = .0012; p = .0693) and isotype control (p = .001; p = .0021). Percentage of neutrophil-RBC aggregates was decreased when incubated with anti-GPA compared to isotype control (p < .01)., Conclusions: Neutrophils and monocytes in peripheral blood exposed to an antibody directed against GPA on RBC surfaces, such as M or N antigens, may be primed towards an activated phenotype., (© 2021 AABB.)

Abstract: The transfusion of blood products is a widely used practice but comes with the risk of transfusion-associated adverse events and fatalities. The primary aim of this study was to evaluate if strict adherence to transfusion guidelines would lead to a decrease in the rate of transfusion reactions that occurred when blood products were given outside of established indications. Hospital-wide educational programs and dedicated electronic transfusion order sets were used to encourage adherence to guidelines. A secondary aim of this study was to evaluate if a decrease in the incidence of transfusion reactions also lead to a decrease in associated healthcare costs., Competing Interests: The authors declare no conflicts of interest., (Copyright © 2021 National Association for Healthcare Quality.)

Background: In the setting of suspected septic transfusion reactions, bacterial culture of both the transfused patient and the residual blood component is recommended. Primary bacterial contamination can occur at the time of component collection. Clinically insignificant "secondary contamination" can occur during post-transfusion component discard, retrieval for culture, or manipulation of the bag at the time of culture sampling., Study Design and Methods: This retrospective, multi-center study analyzes positive residual component culture results and companion patient blood cultures from 15 hospitals, 1 blood center, and all cultured transfusion reactions within the province of Quebec, Canada, over a 5-year period. Imputability was assigned as "definite" (concordant growth), "possible" (discordant growth or lack of growth in patient culture), or "unable to assess" (patient not cultured)., Results: There were 373 positive component cultures from 360 unique transfusion reactions, with 276 (76.7%) companion patient blood cultures performed, of which 10 (2.8%) yielded the pathogen detected in the positive component. Of these 10 definite pathogens, 7 (2 Staphylococcus aureus, 3 other staphylococci, and 1 Streptococcus pyogenes and 1 Bacillus sp.) were associated with platelet and 3 (Aeromonas veronii, Staphylococcus epidermidis, and Enterococcus faecalis) with RBC transfusions. RBC and plasma components comprised 70% of positive component cultures., Discussion: The process of performing residual component culture is vulnerable to secondary contamination. The significance of microorganisms recovered from component culture cannot be interpreted in isolation. In the context of low prevalence of primary contamination of blood components, the positive predictive value of a positive component culture result is very low., (© 2021 AABB.)

Background: Convalescent plasma is being used widely as a treatment for coronavirus disease 2019 (COVID-19). However, the clinical efficacy of COVID-19 convalescent plasma is unclear., Methods: The Passive Immunity Trial for Our Nation (PassITON) is a multicenter, placebo-controlled, blinded, randomized clinical trial being conducted in the USA to provide high-quality evidence on the efficacy of COVID-19 convalescent plasma as a treatment for adults hospitalized with symptomatic disease. Adults hospitalized with COVID-19 with respiratory symptoms for less than 14 days are eligible. Enrolled patients are randomized in a 1:1 ratio to 1 unit (200-399 mL) of COVID-19 convalescent plasma that has demonstrated neutralizing function using a SARS-CoV-2 chimeric virus neutralization assay. Study treatments are administered in a blinded fashion and patients are followed for 28 days. The primary outcome is clinical status 14 days after study treatment as measured on a 7-category ordinal scale assessing mortality, respiratory support, and return to normal activities of daily living. Key secondary outcomes include mortality and oxygen-free days. The trial is projected to enroll 1000 patients and is designed to detect an odds ratio ≤ 0.73 for the primary outcome., Discussion: This trial will provide the most robust data available to date on the efficacy of COVID-19 convalescent plasma for the treatment of adults hospitalized with acute moderate to severe COVID-19. These data will be useful to guide the treatment of COVID-19 patients in the current pandemic and for informing decisions about whether developing a standardized infrastructure for collecting and disseminating convalescent plasma to prepare for future viral pandemics is indicated., Trial Registration: ClinicalTrials.gov NCT04362176 . Registered on 24 April 2020.

Managing a platelet blood product inventory in a hospital-based transfusion service (TS) is challenging. Thus, to optimize platelet inventory availability and to prevent excess outdating, most tertiary care center-based TSs do not require ABO-identical platelet (PLT) transfusions. To mitigate the risk of hemolysis associated with the transfusion of high titer ABO antibody-containing PLT, our institutional policy allows the transfusion of PLT containing ABO-incompatible plasma only if PLT is re-suspended in platelet additive solution (PAS). Despite the steps taken to reduce the risk of hemolytic transfusion reactions to PLT transfusions at our institution, our center has observed hemolytic reactions to PLT in PAS. The current case study highlights the importance of recognizing a hemolytic reaction (HTR) from ABO-incompatible PLT transfusions and discusses the current strategies and recommendations to mitigate this risk., (© 2021 by the Association of Clinical Scientists, Inc.)

Background: Growth in size and complexity of clinical hematopoietic progenitor cell (HPC) transplant programs necessitates parallel increases in cellular therapy laboratory (CTL) workload. Typically individually developed, HPC product processing is labor and time intensive. Variation in procedure type and numbers across CTLs complicates direct comparisons, and benchmark data are not readily available., Study Design and Methods: Studies were undertaken at seven CTLs. Transplant volume and staff numbers were determined. Staff recorded time performing tasks broken down into steps: paperwork, product acceptance, transport/infusion, processing, and cryopreservation. Times were added to obtain total times for 15 common CTL procedures., Results: Annual transplant volume ranged from 53.4 to 463.2, with products processed by a range of 2 to 10 dedicated CTL staff. Paperwork time constituted 23.7% to 62.3% total time; product processing time accounted for 1.8 (for National Marrow Donor Program product receipt) to 62.6% (for red blood cell reduction of allogeneic HPC products from bone marrow) of total processing time. Mean time for 15 procedures ranged from 1.27 to 8.28 hours (standard deviation range, 0.35-2.71 hr). Mean time for products from bone marrow versus peripheral blood was 6.6 ± 2.0 versus 5.5 ± 1.1 hours (p = 0.02). Cryopreservation (6.5 ± 1.6 vs. 4.4 ± 0.85 hr; p < 0.01) and manipulation (6.4 ± 1.5 vs. 4.4 ± 0.85 hr; p < 0.01) added time., Conclusion: CTL procedures are time intensive, with wide intra- and inter-CTL variation. Paperwork accounted for substantial portion of total time across procedures. Bone marrow source, cryopreservation, and manipulation contributed to longer times. These findings provide concrete data on which to build regarding CTL workload capacity., (© 2020 AABB.)

Background: Culture-derived mesenchymal stromal cells (MSCs) exhibit variable characteristics when manufactured using different methods and different source materials. The purpose of this study was to assess the impact on MSC characteristics when different laboratories propagated MSCs from cultures initiated with BM aliquots derived from the same donor source material., Methods and Methods: Five aliquots from each of three different BM donors were distributed to five independent laboratories. Three laboratories plated whole BM and two laboratories a mononuclear BM cell fraction. Four laboratories cultured in media supplemented with fetal bovine serum (FBS) and one laboratory used human platelet lysate (hPL). Initial cell seeding densities (i.e., P0) ranged from 19.7 × 10 3 /cm 2 -282 × 10 3 /cm 2 and for second seeding (i.e., P1) 0.05 × 10 3 -5.1 × 10 3 cells/cm 2 . Post-thawed MSCs from each laboratory were analyzed for cell viability, immunophenotype, tri-lineage differentiation, fibroblast colony-forming units (CFU-F), gene expression, and immunosuppressive activity., Results: Transit times from BM collection to receipt by laboratories located in the United States ranged from 16.0-30.0 h and from 41.5-71.5 h for a laboratory in Asia. Post-thaw culture derived MSCs rom BM #1, #2, and #3 exhibited viabilities that ranged from 74-92%, 61-96%, and 23-90%, respectively. CFU activity from BM #1, #2, and #3 per 200 MSCs plated averaged 45.1 ± 21.4, 49.3 ± 26.8 and 14.9 ± 13.3, respectively. No substantial differences were observed in immunophenotype, and immunosuppressive activities. Global gene expression profiles of MSCs revealed transcriptome differences due to different inter-laboratory methods and to donor source material with the center effects showing greater molecular differences than source material., Conclusion: Functional and molecular differences exist among MSCs produced by different centers even when the same BM starting material is used to initiate cultures. These results indicated that manufacturing of MSCs by five independent centers contributed more to MSC variability than did the source material of the BM used in this study. Thus, emphasizing the importance of establishing worldwide standards to propagate MSCs for clinical use., (Copyright © 2020 Stroncek, Jin, McKenna, Takanashi, Fontaine, Pati, Schäfer, Peterson, Benedetti and Reems.)

Background Aims: At the frontier of transfusion medicine and transplantation, the field of cellular therapy is emerging. Most novel cellular therapy products are produced under investigational protocols with no clear standardization across cell processing centers. Thus, the purpose of this study was to uncover any variations in manufacturing practices for similar cellular therapy products across different cell processing laboratories worldwide., Methods: An exploratory survey that was designed to identify variations in manufacturing practices in novel cellular therapy products was sent to cell processing laboratory directors worldwide. The questionnaire focused on the manufacturing life cycle of different cell therapies (i.e., collection, purification, in vitro expansion, freezing and storage, and thawing and washing), as well as the level of regulations followed to process each product type., Results: The majority of the centers processed hematopoietic progenitor cells (HPCs) from peripheral blood (n = 18), bone marrow (n = 16) or cord blood (n = 19), making HPCs the most commonly processed cells. The next most commonly produced cellular therapies were lymphocytes (n = 19) followed by mesenchymal stromal cells (n = 14), dendritic cells (n = 9) and natural killer (NK) cells (n = 9). A minority of centers (<5) processed pancreatic islet cells (n = 4), neural cells (n = 3) and induced-pluripotent stem cells (n = 3). Thirty-two laboratories processed products under an investigational status, for either phase I/II (n = 27) or phase III (n = 17) clinical trials. If purification methods were used, these varied for the type of product processed and by institution. Environmental monitoring methods also varied by product type and institution., Conclusion: This exploratory survey shows a wide variation in cellular therapy manufacturing practices across different cell processing laboratories. A better understanding of the effect of these variations on the quality of these cell-based therapies will be important to assess for further process evaluation and development., (Copyright © 2020 International Society for Cell and Gene Therapy. All rights reserved.)

Background: Whole blood (WB) is rapidly emerging as the treatment modality of choice for the initial resuscitation of civilian trauma patients across the United States. The reemergence of WB has been rapid and driven in part by recognition of the importance of early plasma transfusion in the resuscitation process., Study Design and Methods: The study was designed as a critical analysis of the available literature on WB transfusion in civilian trauma patients. Studies were included if they reported on transfusion of cold-stored WB used in a civilian setting and measured safety, feasibility, or a direct clinical outcome., Results: Examination of the available literature supports the feasibility and safety of WB used in treatment of civilian trauma patients. The evidence regarding clinical outcomes, particularly with direct comparison to equivalent doses of component therapy, is more limited. The literature is predominantly descriptive and retrospective in nature and limited by the heterogeneity of clinical WB protocols being used. Based on this limited data set, there are limited conclusions that can be used to definitely support or refute the clinical superiority of WB to component therapy., Conclusion: Current literature supports the safety and feasibility of WB, but prospective randomized trials comparing WB to component therapy are needed to provide the definitive evidence on this topic., (© 2020 AABB.)

The complement is a key player of the innate immune response. It provides defense mechanisms that are not specific, but very efficient at neutralizing any invader, accounting for 4% of the proteins in the peripheral blood. Nevertheless, there is a dark side to the complement system, as it may activate its machinery against healthy cells such as peripheral blood red blood cells and platelets resulting in undesired hemolysis and thrombocytopenia, respectively. Understanding and identifying the role of complement in these settings allow physicians to adjust their diagnostic and therapeutic modalities accordingly. The role of complement in the pathophysiology and management of autoimmune hemolytic anemia and of alloimmune-mediated thrombocytopenia is under investigation and discussed., (Copyright © 2019 Société française de transfusion sanguine (SFTS). Published by Elsevier Masson SAS. All rights reserved.)

Background: Culturing residual blood components after suspected septic transfusion reactions guides management of patients and cocomponents. Current practice, accuracy of provider vital sign assessment, and performance of the AABB culture criteria are unknown. A multicenter international study was undertaken to investigate these issues and develop improved culture criteria., Study Design and Methods: Retrospective data for all transfusion reactions resulting in residual blood component culture in 2016 were collected from participating hospitals. The performance of the AABB culture criteria were assessed for detection of positive culture results. Modifications to the AABB criteria including 1) recommending culturing in the setting of isolated high fevers, 2) defining hypotension and tachycardia using objective parameters, and 3) incorporating antipyretic use were tested to determine if modifications improved performance. Modifications associated with improvement were incorporate into the BEST criteria. The AABB and the BEST criteria were then tested against a data set enriched for positive culture results to determine which criteria were superior., Results: Data were collected from 20 centers encompassing 779,143 transfusions, 3,187 reported transfusion reactions, and 1,104 cultured components. There was marked variation in reaction reporting and culturing rates (0.0%-100.0%). Of 35 total positive component cultures, only one of 35 (2.9%) had concordant patient cultures; 12 of 34 (35.3%) did not have patient cultures performed. The BEST criteria had better sensitivity for detection of a positive culture result compared to the AABB criteria (74% vs. 41%), although specificity decreased (45% vs. 65%)., Conclusion: Compared to the AABB criteria, the BEST criteria have improved sensitivity for positive culture detection., (© 2019 AABB.)

Background: Viability testing is a common practice in laboratories. The goal of this study was to ascertain current laboratory practices internationally for performing viability testing for cryopreserved cord blood (CB) products and glean information about how to standardize the method to improve interlaboratory reproducibility., Study Design and Methods: A survey to evaluate current laboratory practices for viability testing was designed and distributed internationally. The question topics included sampling and testing methods, responses to unexpected results, and the rating of the reliability of the CB quality tests, together with expectations for standardization., Results: There were 32 respondents to the survey, of whom 28 responded to the more detailed questionnaire about viability methods. Overall, responses indicated that various stains were used among the laboratories, and when multiple sites used the same viability stain the methods differed. The majority of the respondents were in favor of standardizing the viability testing methods. A wide variety of preferences were communicated about how to standardize the method, but a majority did advocate the use of 7-aminoactinomycin D (7-AAD) with flow cytometry., Conclusions: The survey results revealed a variety of tests and inconsistent interlaboratory practices for performing the viability assay. Flow cytometry with a 7-AAD dye was suggested as a first step toward standardization., (© 2018 AABB.)

Silk fibroin is a novel biomaterial for enhancing transplanted islet cell function and survival. This study investigated whether silk fibroin may have unique properties that improve islet function in the face of inflammatory-mediated stress during transplantation. Murine islet function was tested in vitro with either silk fibroin or alginate and challenged with inflammatory cytokines. The glucose-stimulated insulin secretion index for all conditions decreased with inflammatory cytokines, but was better preserved for islets exposed to silk compared to those exposed to alginate or medium. GLUT2 transporter expression on the cell surface of islets exposed to silk was increased compared to alginate or medium alone. Upon cytokine stress, a greater percentage of islet cells exposed to silk expressed GLUT2 on their surface. We conclude that preconditioning islets with silk fibroin stimulates islet cell surface GLUT2 expression, an increase, which persists under inflammatory stress, and may improve islet engraftment and function after transplantation., (Copyright © 2018 Elsevier Inc. All rights reserved.)

Background: Establishing transfusion guidelines during trauma resuscitation is challenging. Our objective was to evaluate indications for transfusion in trauma patients who emergently received ≤2 units of red blood cells (RBC) during the first hour of resuscitation., Methods: A single center retrospective study included non-massively bleeding trauma patients stratified into 2 groups: 1) with a clinical indication for transfusion and 2) with no indication for transfusion. Admission vital signs (VS), injury severity score (ISS), shock index, and laboratory values were compared between the two groups using the Wilcoxon rank-sum test., Results: Among 111 non-massively bleeding trauma patients, 40 presented no indication for transfusion. All patients presented similar ISS and VS. The 71 patients presenting with an indication for transfusion had higher bicarbonate (22.6 vs 20.8) and lower lactate levels (4.7 v 6.6) ( p <0.05)., Conclusion: Lactate and bicarbonate blood levels may be potential indicators for RBC transfusion need during trauma resuscitation in non-massively bleeding patients., (© 2018 by the Association of Clinical Scientists, Inc.)

Objectives: Inconclusive RBC antibody identification (ABID) may delay RBC crossmatch. An increased number of inconclusive ABID was observed, and an algorithm was developed to improve ABID efficiency., Methods: RBC antibody screen (AS) and ABID were initially performed using solid-phase RBC adherence assay (SPRCA) and manual tube method. A retrospective analysis of AS and ABID results was performed pre- and postalgorithm implementation., Results: The number of inconclusive ABID results decreased from 26 to six per month pre- and postimplementation, respectively. SPRCA became the primary AS method, and manual tube became the gold standard for ABID. SPRCA was used for ABID upon reference specialist secondary review and allowed identification of 30 specific RBC antibodies, for which no patients developed signs or symptoms of a hemolytic transfusion reaction., Conclusions: RBC reference workflow using SPRCA and manual tube methods for AS and ABID decreases "inconclusive" ABID without adverse events., (© American Society for Clinical Pathology, 2017. All rights reserved. For permissions, please e-mail: journals.permissions@oup.com)

Background: Allergic transfusion reactions are drawbacks to the benefits of transfusion. Classically, allergic transfusion reactions depend on histamine release from mast cells or basophils, but other leukocyte subsets may also be important. Thus, we propose to better define the exact leukocyte subsets involved in allergic transfusion reactions., Study Design and Methods: The overall objective of the current study was to compare the activation of specific peripheral blood leukocyte subsets (monocytes, neutrophils, eosinophils, and basophils) in a cohort of 13 patients who received chronic transfusions and had a history of allergic transfusion reactions compared with a control group of patients who received chronic transfusions and had no history of allergic transfusion reactions. Leukocyte subsets were analyzed by flow cytometry at baseline and after red blood cell transfusion, and cytokine levels in platelet-free plasma collected at the same time points were measured by Luminex assay., Results: Flow cytometry and cytokine profiles before and after transfusion did not differ significantly between patients who did and did not have a history of allergic transfusion reactions (p > 0.05). However, post-transfusion samples from both groups showed a decrease in CD63 expression in basophils, monocytes, and eosinophils and a decrease in CD45 expression in all leukocyte subsets compared with pretransfusion samples. Interleukin 10 levels increased after transfusion in the group with a history of allergic transfusion reactions (p = 0.0469), and RANTES (regulated upon activation, normal T-cell expressed and secreted) was significantly decreased post-transfusion in all patients (p = 0.0122)., Conclusion: None of the leukocyte subsets from patients who had a history of allergic transfusion reactions significantly increased in activation either before or after transfusion. All leukocyte subsets from patients who did and did not have a history of allergic transfusion reactions decreased in their activation profile upon transfusion challenge., (© 2017 AABB.)

Background: Transfusion-transmitted babesiosis (TTB) has been rapidly increasing in incidence since the beginning of the 21st century. Asymptomatic individuals with Babesia infection are able to donate blood in the United States because of the lack of specific blood donation testing. Blood products collected in Babesia-endemic areas are distributed nationally; thus, clinicians in nonendemic states may fail to include babesiosis in the differential diagnosis of a patient who had a recent transfusion history and a fever of unknown origin., Study Design and Methods: We report the details of two cases of clinical transfusion-transmitted babesiosis and one asymptomatic infection identified in red blood cell recipients in two nonendemic states (South Carolina and Maryland), which, when combined with three recent additional cases in nonendemic states, totals six recipient infections in three nonendemic states., Results: Delayed diagnosis of transfusion-transmitted babesiosis places patients at risk for increased morbidity and mortality and may result in clinical mismanagement or unnecessary treatments. A peripheral blood smear should be reviewed in any patient with a recent transfusion and a fever of unknown origin. Prompt communication of the diagnosis among physicians is key to ensuring that patients with transfusion-transmitted babesiosis are treated expeditiously, and a transfusion service investigation is necessary to identify additional recipients from the same donor., Conclusion: TTB is appearing in traditionally nonendemic states because of blood product distribution patterns. Clinicians should include TTB on the differential diagnosis in any patient presenting who had a recent transfusion history and a fever of unknown origin, regardless of where the transfusion took place., (© 2017 AABB.)

The success of pancreatic islet (PI) transplantation is challenged by PI functional damage during the peritransplantation period. A silk-based encapsulation platform including mesenchymal stromal cells (MSCs) was evaluated for islet cell delivery in vivo. Islet equivalents (IEQs) were transplanted into the epididymal fat pads of mice with streptozotocin-induced diabetes. Three PI combinations were tested: (A) co-encapsulated in silk with MSCs; (b) encapsulated in silk alone; or (c) pelleted. Blood glucose levels were monitored and intraperitoneal glucose tolerance test (IPGTT) was performed upon return to euglycaemia. Grafts were removed for histology and cytokine content analysis. Mice with PI grafts in silk showed a prompt return to euglycaemia. IPGTT was significantly improved with PI in silk with MSCs, compared to PI in silk alone or pelleted. Both Th 1 and Th 2 cytokines were increased in PI grafts in silk, but Th 1 cytokines were decreased significantly with PI and MSC co-encapsulation. Histological analysis showed osteogenesis and chondrogenesis in the silk grafts containing MSCs. Future studies will evaluate MSC stability and function in vivo and improve silk biocompatibility for applications in islet transplantation. Copyright © 2015 John Wiley & Sons, Ltd., (Copyright © 2015 John Wiley & Sons, Ltd.)

Background: Red blood cell transfusion related to select surgical procedures accounts for approximately 2.8 million transfusions in the United States yearly and occurs commonly after hip fracture surgeries. Randomized controlled trials have demonstrated lack of clinical benefit with higher versus lower transfusion thresholds in postoperative hip fracture repair patients with cardiac disease or risk factors for cardiac disease. The economic implications of a higher versus lower hemoglobin (Hb) threshold have not yet been investigated., Study Design and Methods: A decision tree analysis was constructed to estimate differences in healthcare costs and charges between a Hb transfusion threshold strategy of 8 g/dL versus 10 g/dL from the perspective of both Centers for Medicare and Medicaid Services (CMS) as well as hospitals. Secondary outcome measures included differences in transfusion-related adverse events., Results: Among the 133,697 Medicare beneficiaries undergoing hip fracture repair in 2012, we estimated that 45,457 patients would be anemic and at risk for transfusion. CMS would save an estimated $11.3 million to $24.3 million in payments, while hospitals would reduce charges by an estimated $52.7 million to $93.6 million if the restrictive transfusion strategy were to be implemented nationally. Additionally, rates of transfusion-associated circulatory overload, transfusion-related acute lung injury, acute transfusion reactions, length of stay, and mortality would be reduced., Conclusions: This model suggests that the uniform adoption of a restrictive transfusion strategy among patients with cardiac disease and risk factors for cardiac disease undergoing hip fracture repair would result in significant reductions in clinically important outcomes with significant cost savings., (© 2016 AABB.)

Background: Clinical studies have demonstrated that the early and empiric use of plasma improves survival after hemorrhagic shock. We have demonstrated in rodent models of hemorrhagic shock that resuscitation with plasma is protective to the lungs compared with lactated Ringer's solution. As our long-term objective is to determine the molecular mechanisms that modulate plasma's protective effects in injured bleeding patients, we have used human plasma in a mouse model of hemorrhagic shock. The goal of the current experiments is to determine if there are significant adverse effects on lung injury when using human versus mouse plasma in an established murine model of hemorrhagic shock and laparotomy., Methods: Mice underwent laparotomy and 90 minutes of hemorrhagic shock to a mean arterial pressure (MAP) of 35 ± 5 mm Hg followed by resuscitation at 1× shed blood using either mouse fresh frozen plasma (FFP), human FFP, or human lyophilized plasma. Mean arterial pressure was recorded during shock and for the first 30 minutes of resuscitation. After 3 hours, animals were killed, and lungs collected for analysis., Results: There was a significant increase in early MAP when mouse FFP was used to resuscitate animals compared with human FFP or human lyophilized plasma. However, despite these differences, analysis of the mouse lungs revealed no significant differences in pulmonary histopathology, lung permeability, or lung edema between all three plasma groups. Analysis of neutrophil infiltration in the lungs revealed that mouse FFP decreased neutrophil influx as measured by neutrophil staining; however, myeloperoxidase immunostaining revealed no significant differences in between groups., Conclusion: The study of human plasma in a mouse model of hemorrhagic shock is feasible but does reveal some differences compared with mouse plasma-based resuscitation in physiologic measures such as MAP postresuscitation. Measures of end organ function such as lung injury appear to be comparable in this acute model of hemorrhagic shock and resuscitation., Competing Interests: The authors have no conflicts of interest to report

In the last 10 years, the role of mesenchymal stromal cells (MSCs) in modulating inflammatory and immune responses has been characterized using both in vitro studies and in vivo models of immune disorders. Mesenchymal stromal cell immunomodulatory properties have been linked to various paracrine factors which expression varies depending on the pathologic condition to which the MSCs are exposed. These factors may directly impact key cells of the adaptive immune system, such as T cells. Indeed, coculturing MSCs with T cells in a mixed lymphocyte reaction assay inhibits T-cell proliferation through the secretion of immunomodulatory cytokines. However, in a context of inflammation, MSCs may secrete paracrine factors that influence other immune cell subpopulations such as dendritic cells and macrophages and polarize them toward a tolerogenic phenotype. In vivo, these same immunomodulatory factors are shown to be increased in the serum of animal models presenting with inflammatory diseases treated with MSC administration. In light of the results from these landmark studies, we review the main MSC secreted factors identified to play a role in modulating inflammatory immune responses either in vitro or in vivo, and we assess the impact of these factors on the therapeutic applications of MSC-based cell therapies in immune diseases., (Copyright © 2015 Elsevier Inc. All rights reserved.)

Blood group incompatibility remains a significant barrier to kidney transplantation. Approximately, one-third of donors are blood group incompatible with their intended recipient. Options for these donor-recipient pairs include blood group incompatible transplantation or kidney paired donation. However, the optimal protocol for blood group incompatible transplantation is unknown. Protocols differ in techniques to remove ABO antibodies, titer targets, and immunosuppression regimens. In addition, the mechanisms of graft accommodation to blood group antigens remain poorly understood. We describe a blood group incompatible protocol using pretransplant therapeutic plasma exchange (TPE), high-dose intravenous immunoglobulin, and rituximab in addition to prednisone, mycophenolate mofetil, and tacrolimus. In this protocol, we do not exclude patients based on a high initial titer and do not implement post-transplant TPE. All 16 patients who underwent this protocol received a living donor transplant with 100% patient and graft survival, and no reported episodes of antibody-mediated rejection to date with a median follow-up of 2.6 years (range 0.75-4.7 years). We conclude that blood group incompatible transplantation can be achieved without post-transplant TPE., (© 2015 Wiley Periodicals, Inc.)

Background: Plasma volume reduction (PVR) may reduce the risk of hemolysis associated with transfusion of plateletpheresis blood products (PLTs) containing ABO-incompatible plasma. But PVR may delay PLT issue. In collaboration with our blood donor center we evaluated an automated screen of PLT for high-titer ABO antibody and to apply PVR to high-titer PLTs., Study Design and Methods: At the donor center, plasma from PLT donors was tested using an automated microplate system (PK7300, Beckman). PK settings were set for a detection cutoff equivalent to 1 in 256 using a manual tube method. The donors associated with high-titer PLTs were characterized by sex and age. In the transfusion service, the number of PVR procedures was evaluated before and after implementation of the high-titer screen., Results: During validation, 157 of 1008 PLT units (15%) were positive by the automated method versus 121 (12%) by manual method. After implementation, 2112 of 15,240 PLT units were high-titer, with higher frequency in donations from females versus males (18% vs. 12%, p < 0.0001). The PLT PVR rate was reduced by 50%., Conclusion: Implementation of an automated method to screen PLTs for high-titer ABO antibody at the donor center improves the inventory management of PLTs containing ABO-incompatible plasma at the hospital transfusion service., (© 2015 AABB.)

Background: The Pragmatic, Randomized Optimal Platelets and Plasma Ratios (PROPPR) trial was a randomized clinical trial comparing survival after transfusion of two different blood component ratios for emergency resuscitation of traumatic massive hemorrhage. Transfusion services supporting the study were expected to provide thawed plasma, platelets, and red blood cells within 10 minutes of request., Study Design and Methods: At the 12 Level 1 trauma centers participating in PROPPR, blood components transfused and delivery times were tabulated, with a focus on universal donor (UD) plasma management. The adequacy of site plans was assessed by comparing the bedside blood availability times to study goals and the new American College of Surgeons guidelines., Results: Eleven of 12 sites were able to consistently deliver 6 units of thawed UD plasma to their trauma-receiving unit within 10 minutes and 12 units in 20 minutes. Three sites used blood group A plasma instead of AB for massive transfusion without complications. Approximately 4700 units of plasma were given to the 680 patients enrolled in the trial. No site experienced shortages of AB plasma that limited enrollment. Two of 12 sites reported wastage of thawed AB plasma approaching 25% of AB plasma prepared., Conclusion: Delivering UD plasma to massively hemorrhaging patients was accomplished consistently and rapidly and without excessive wastage in high-volume trauma centers. The American College of Surgeons Trauma Quality Improvement Program guidelines for massive transfusion protocol UD plasma availability are practicable in large academic trauma centers. Use of group A plasma in trauma resuscitation needs further study., (© 2015 AABB.)

Context: Hemoglobinuria was observed after packed red blood cell transfusion in a series of patients at our pediatric treatment center. Laboratory testing was suggestive of intravascular hemolysis with no support for an immunohematologic process., Objective: We investigated these adverse events to define a quality improvement plan and to prevent future hemolytic adverse events. Multiple factors were investigated, and the only change identified was the implementation of a new infusion pump (Pump A) that replaced a previous model (Pump B)., Design: In vitro pump analyses, a retrospective review of urinalyses, and prospective urinalysis and nursing surveillances were also performed., Results: In in vitro analysis of the pumps, irradiated units with higher hematocrit at a low flow rate through Pump A had a greater than thirty-fold increase in free hemoglobin from baseline compared to minimal free hemoglobin changes seen with Pump B. Irradiated units with a lower hematocrit had a minimal change in free hemoglobin from baseline with both Pumps A and B at either low or high flow rate. Subsequently, only units with lower hematocrits were issued for transfusion of pediatric patients, and Pump A was replaced by Pump B in the outpatient unit. Retrospective and prospective surveillances found no additional unexplained cases of gross hemoglobinuria associated with transfusion., Conclusion: The investigation determined that infusion of higher hematocrit units using a specific commercial pump was associated with mechanical hemolysis. The change to units with lower hematocrit through an alternative pump has been an effective corrective action to date., (© 2015 by the Association of Clinical Scientists, Inc.)

Background: Documented transfusion-associated hepatitis A (TAHA) is rare, and blood donors in the United States are not routinely screened for this infection. We report a case of TAHA associated with a donation made 8 days after a donor returned from a trip to South America., Study Design and Methods: This is a review of donor and recipient records and a review of the literature., Results: A donor developed symptoms of hepatitis 20 days after donation (28 days after returning from South America). The donor reported the illness 56 days after donation when contacted to schedule another visit. By this time, the red blood cell and frozen plasma components had been transfused. The recipient of the plasma, a 15-month-old female, tested positive for immunoglobulin M antibody to hepatitis A virus 43 days after transfusion. The recipient had displayed mild, nonspecific symptoms approximately 2 weeks after transfusion. Hospital infection control investigated the potential for further spread within the hospital because the recipient had been an inpatient for most of the posttransfusion period. The risk of transmission to other patients was determined to be negligible because the patient had been in isolation for other reasons. Family members, who included a health care professional, were counseled and offered prophylaxis., Conclusion: TAHA may be underrecognized. This case was identified only because of a donor report at the time of recruitment. Asymptomatic donor viremia has been documented in plasma donors. Although TAHA rarely results in severe disease, the risk it creates of secondary transmission especially within the hospital setting is not inconsequential., (© 2014 AABB.)

Background: The Gerbich (Ge) blood group system consists of 11 antigens carried on red blood cell (RBC) membrane glycophorins C and D; of these, Ge:3 antigen is of high prevalence, and the anti-Ge3 is found to be clinically significant., Case Report: A 34-week neonate born to a Hispanic mother with anti-Ge3 developed late-onset hemolysis with hyperbilirubinemia and was successfully treated with transfusions from her mother. Relevant clinical findings and laboratory results for this case are summarized and compared to three other previously reported cases; all babies were born from a mother of Hispanic ethnicity., Conclusion: Hemolytic disease of the fetus and new born associated with anti-Ge3 is rare but should be considered when working up a broadly reactive RBC antibody screen in women of Hispanic ethnicity. Early identification of pregnant women with anti-Ge3 is recommended for prenatal transfusion planning and close monitoring of the newborn infant for evidence of late-onset anemia., (© 2012 American Association of Blood Banks.)

Protein polymer-based hydrogels have shown potential for tissue engineering applications, but require biocompatibility testing for in vivo use. Enzymatically crosslinked protein polymer-based hydrogels were tested in vitro and in vivo to evaluate their biocompatibility. Endotoxins present in the hydrogel were removed by Trition X-114 phase separation. The reduction of endotoxins decreased TNF-α production by a macrophage cell line in vitro; however, significant inflammatory response was still present compared to collagen control gels. A branched PEG molecule and dexamethasone were added to the hydrogel to reduce the response. In vitro testing showed a decrease in the TNF-α levels with the addition of dexamethasone. In vivo implantations into the epididymal fat pad of C57/BL6 mice, however, indicated a decreased inflammatory mediated immune response with a hydrogel treated with both PEGylation and endotoxin reduction. This study demonstrates the importance of endotoxin testing and removal in determining the biocompatibility of biomaterials.

Biomaterial encapsulation of islets has been proposed to improve the long-term success of islet transplantation by recreating a suitable microenvironment and enhancing cell-matrix interactions that affect cellular function. Protein polymer hydrogels previously showed promise as a biocompatible scaffold by maintaining high cell viability. Here, enzymatically-crosslinked protein polymers were used to investigate the effects of varying scaffold properties and of introducing ECM proteins on the viability and function of encapsulated MIN6 β-cells. Chemical and mechanical properties of the hydrogel were modified by altering the protein concentrations while collagen IV, fibronectin, and laminin were incorporated to reestablish cell-matrix interactions lost during cell isolation. Rheology indicated all hydrogels formed quickly, resulting in robust, elastic hydrogels with Young's moduli similar to soft tissue. All hydrogels tested supported both high MIN6 β-cell viability and function and have the potential to serve as an encapsulation platform for islet cell delivery in vivo.

Pancreatic islet encapsulation within biosynthetic materials has had limited clinical success due to loss of islet function and cell death. As an alternative encapsulation material, a silk-based scaffold was developed to reestablish the islet microenvironment lost during cell isolation. Islets were encapsulated with ECM proteins (laminin and collagen IV) and mesenchymal stromal cells (MSCs), known to have immunomodulatory properties or to enhance islet cell graft survival and function. After a 7 day in vitro encapsulation, islets remained viable and maintained insulin secretion in response to glucose stimulation. Islets encapsulated with collagen IV, or laminin had increased insulin secretion at day 2 and day 7, respectively. A 3.2-fold synergistic improvement in islet insulin secretion was observed when islets were co-encapsulated with MSCs and ECM proteins. Furthermore, encapsulated islets had increased gene expression of functional genes; insulin I, insulin II, glucagon, somatostatin, and PDX-1, and lower expression of the de-differentiation genes cytokeratin 19 and vimentin compared to non-encapsulated cells. This work demonstrates that encapsulation in silk with both MSCs and ECM proteins enhances islet function and with further development may have potential as a suitable platform for islet delivery in vivo., (Copyright © 2012 Elsevier Ltd. All rights reserved.)

Background: Recent studies show that transfusing older blood may lead to increased mortality. This raises the issue of whether transfusing fresher blood can be achieved without jeopardizing blood availability., Study Design and Methods: We propose a simple family of policies that is defined by a single threshold: rather than transfusing the oldest available blood that is younger than 42 days, we transfuse the oldest blood that is younger than the threshold, and if there is no blood younger than the threshold then we transfuse the youngest blood that is older than the threshold. To assess this policy, we build a simulation model using data from Stanford University Medical Center. We focus on the tradeoff between the mean age of transfused blood and the fraction of transfused blood that is imported., Results: For hospitals in which the local supply is greater than demand, our policy with a threshold of 14 days leads to a decrease of 10 to 20 days in the mean age of transfused blood while increasing the fraction of imported blood to less than 0.005 (i.e., 0.5%). If the health benefits from transfusing fresher blood can be confirmed by randomized clinical trials, then conservative assumptions suggest that this policy could reduce the annual number of transfused patients who die within 1 year by 20,000., Conclusion: The proposed allocation policy with a threshold of 14 days could allow many US hospitals to significantly reduce the age of transfused blood, thereby possibly reducing morbidity and mortality, while having a negligible impact on supply chain operations., (© 2011 American Association of Blood Banks.)

Background: Immune refractoriness to platelet (PLT) transfusion is primarily due to HLA antibody. Patients at our institution are identified as refractory due to HLA by a Luminex-based immunoglobulin (Ig)G-single-antigen-bead (SAB) assay, but in highly sensitized patients, antigen-negative compatible donors cannot be found due to the high sensitivity of the IgG-SAB method. We developed an assay that detects only HLA antibodies binding the first complement component (C1q). We hypothesized that the C1q-SAB method might be more relevant than the IgG-SAB method because the antibodies identified may activate the complement cascade causing PLT destruction., Study Design and Methods: Thirteen highly sensitized refractory patients received 177 PLT units incompatible by the IgG-SAB method. They were retrospectively retested by the C1q-SAB method. Calculated percent reactive antibody (CPRA) and HLA antibody specificities were compared between the two methods and corrected count increment (CCI) values were analyzed. Additionally the impact of ABO compatibility on CCI responses was evaluated., Results: The mean CPRA value was significantly lower by C1q-SAB (60%) than by IgG-SAB (94%; p < 0.05). Patients showed significantly better CCI (10.6 × 10(9) ± 0.8 × 10(9) /L) with C1q-compatible (n = 134) than with C1q-incompatible PLTs (n = 43) (2.5 × 10(9) ± 0.9 × 10(9) /L/m(2) ; p < 0.0001). ABO compatibility did not significantly impact the CCI values (p < 0.0001). Our results show that 75% of PLT units previously considered incompatible were actually compatible., Conclusion: For highly refractory patients to PLT transfusion, the C1q-based SAB binding assay may be a better method for identifying clinically relevant HLA antibodies and selecting PLT units that will result in acceptable CCI., (© 2011 American Association of Blood Banks.)

Disseminated intravascular coagulation (DIC) due to red cell hemolysis has been previously attributed to transfusion-related hemolytic reactions, but not to autoimmune hemolytic anemia. We report a case of DIC in a child with complement-fixing IgM-mediated cold-agglutinin autoimmune hemolysis, which resulted in arterial thrombosis and gangrene of the upper and lower extremities., (Copyright © 2011 Wiley-Liss, Inc.)