No abstract

Plasma utilization has increased over the last two decades, and there is a growing concern that many plasma transfusions are inappropriate. Plasma transfusion is not without risk, and certain complications are more likely with plasma than other blood components. Clinical and laboratory investigations of the patients suffering reactions following infusion of fresh frozen plasma (FFP) define the etiology and pathogenesis of the panoply of adverse effects. We review here the pathogenesis, diagnosis, and management of the risks associated with plasma transfusion. Risks commonly associated with FFP include: (1) transfusion related acute lung injury; (2) transfusion associated circulatory overload, and (3) allergic/anaphylactic reactions. Other less common risks include (1) transmission of infections, (2) febrile non-hemolytic transfusion reactions, (3) RBC allo-immunization, and (4) hemolytic transfusion reactions. The affect of pathogen inactivation/reduction methods on these risks are also discussed. Fortunately, a majority of the adverse effects are not lethal and are adequately treated in clinical practice.

We investigated feasibility and accuracy of an interferon-gamma release assay (IGRA) for detection of T cell responses to SARS-CoV-2. Whole blood IGRA accurately distinguished between convalescents and uninfected healthy blood donors with a predominantly CD4+ T cell response. SARS-CoV-2 IGRA may serve as a useful diagnostic tool in managing the COVID-19 pandemic.

Introduction Daratumumab (DARA), an IgG1k human monoclonal antibody (Ab) against CD38, is a promising novel therapy for multiple myeloma. However, direct binding of DARA to endogenous CD38 on reagent red blood cells (RBCs) interferes with routine blood bank serologic testing. We recently showed that treating reagent RBCs with DTT eliminates the DARA interference by denaturing cell surface CD38, allowing the safe transfusion of patients on DARA.1 This multicenter international study was aimed at validating the DTT method for use by blood banks worldwide. Methods Participating blood banks received two plasma sample unknowns. Sample 1 was spiked with DARA alone (5 mcg/mL). Sample 2 was spiked with DARA plus a clinically significant RBC Ab (anti-D (Rh immune globulin) or monoclonal anti-Fya or anti-s). Sites were instructed to first perform an Ab screen using their usual method (tube, gel, or solid phase), then to repeat the Ab screen using DTT-treated RBCs (gel or tube). If the Ab screen remained positive with DTT-treated RBCs (Sample 2), sites were to identify the unknown Ab using a DTT-treated RBC panel (gel or tube.) The primary outcome measure was the proportion of sites able to successfully identify the unknown Ab in the presence of DARA. Qualitative data were collected by online survey. Results Paired plasma sample unknowns were shipped to 25 study sites in North America, South America, Europe, Asia, and Australia/New Zealand. Data were received from 23 sites to date (Table). For the initial Ab screen, 10 sites used tube testing, 7 sites used gel, and 6 sites used solid phase. All sites observed DARA interference with the Ab screen (false positive agglutination reactions). All sites reported no DARA interference using DTT-treated RBCs. For Ab identification (Sample 2), 13 sites used tube testing and 10 sites used gel. 23/23 sites (100%) were able to correctly identify the unknown Ab using the DTT method. The Abs identified were: anti-Fya (9/9), anti-s (8/8), and anti-D (6/6). Feedback on the DTT method was mainly positive, with 86% of sites that responded to the survey indicating that they planned to use the DTT method to manage clinical samples from DARA-treated patients. Conclusion DARA consistently interferes with all three Ab screening methods currently used by blood banks (tube, gel, and solid phase.) Using DTT-treated RBCs, 23/23 (100%) of blood bank laboratories from around the world were able to identify a clinically significant Ab initially masked by the presence of DARA. The DTT method is robust, reproducible, and can be implemented by blood banks globally to help provide safe blood products to patients on DARA. As DTT denatures Kell antigens, K- RBC units should be provided when using the DTT method. 1. Chapuy CI, Nicholson RT, Aguad MD, et al. Resolving the daratumumab interference with blood compatibility testing. Transfusion. 2015;55(6pt2):1545-1554. Disclosures Unger: Janssen: Employment. Doshi:Janssen: Employment. Kaufman:Janssen: Consultancy, Research Funding.

Transfusion of red cell concentrates (RCCs) is associated with increased risk of adverse outcomes that may be affected by different blood manufacturing methods and the presence of extracellular vesicles (EVs). We investigated the effect of different manufacturing methods on hemolysis, residual cells, cell-derived EVs, and immunomodulatory effects on monocyte activity. Thirty-two RCC units produced using whole blood filtration (WBF), red cell filtration (RCF), apheresis-derived (AD), and whole blood-derived (WBD) methods were examined (n = 8 per method). Residual platelet and white blood cells (WBCs) and the concentration, cell of origin, and characterization of EVs in RCC supernatants were assessed in fresh and stored supernatants. Immunomodulatory activity of RCC supernatants was assessed by quantifying monocyte cytokine production capacity in an in vitro transfusion model. RCF units yielded the lowest number of platelet and WBC-derived EVs, whereas the highest number of platelet EVs was in AD (day 5) and in WBD (day 42). The number of small EVs (<200 nm) was greater than large EVs (≥200 nm) in all tested supernatants, and the highest level of small EVs were in AD units. Immunomodulatory activity was mixed, with evidence of both inflammatory and immunosuppressive effects. Monocytes produced more inflammatory interleukin-8 after exposure to fresh WBF or expired WBD supernatants. Exposure to supernatants from AD and WBD RCC suppressed monocyte lipopolysaccharide-induced cytokine production. Manufacturing methods significantly affect RCC unit EV characteristics and are associated with an immunomodulatory effect of RCC supernatants, which may affect the quality and safety of RCCs.

Immunosuppressed patients such as solid organ transplant and hematologic malignancy patients appear to be at increased risk for morbidity and mortality due to coronavirus disease 2019 (COVID‐19) caused by SARS coronavirus 2 (SARS‐CoV‐2). Convalescent plasma, a method of passive immunization that has been applied to prior viral pandemics, holds promise as a potential treatment for COVID‐19. Immunocompromised patients may experience more benefit from convalescent plasma given underlying deficits in B and T cell immunity as well as contraindications to antiviral and immunomodulatory therapy. We describe our institutional experience with four immunosuppressed patients (two kidney transplant recipients, one lung transplant recipient, and one chronic myelogenous leukemia patient) treated with COVID‐19 convalescent plasma through Expanded Access Program (NCT 04338360). All patients clinically improved after administration (two fully recovered and two discharged to skilled nursing facilities) and none experienced a transfusion reaction. We also report characteristics of convalescent plasma product from a local blood center including positive SARS‐CoV‐2 IgG and negative SARS‐CoV‐2 PCR in all samples tested. This preliminary evidence suggest that convalescent plasma may be safe among immunosuppressed patients with COVID‐19, and emphasizes the need for further data on efficacy of convalescent plasma as either primary or adjunctive therapy for COVID‐19.

BACKGROUND-TRALI is the leading cause of transfusion-related deaths. Donor HLA antibodies have been implicated in TRALI cases. Blood centers are implementing TRALI risk reduction strategies based on HLA antibody screening of some subpopulations of ever-pregnant apheresis platelet donors. However, if screening assay cutoffs are too sensitive, donation loss may adversely impact blood availability.

This toolkit has been updated to align with FDA's May 11 th Updated Information for Blood Establishments Regarding the Novel Coronavirus Outbreak. •• The 2019 novel coronavirus has been named "SARS-CoV-2" and causes coronavirus disease 2019 (COVID-19). •• FDA has issued these precautionary measures for COVID-19 and continues to state:"There have been no reported cases of transfusion-transmitted coronavirus, including SARS-CoV-2, worldwide.Routine measures used to determine blood donor eligibility prevent individuals with clinical respiratory infections from donating blood. For example, blood donors must be in good health and have a normal temperature on the day of donation (21 CFR 630.10)."This toolkit highlights FDA's changes in the updated information.