Efforts to recruit and enhance blood donor return probability: A point of view from Oslo, Norway.

Transfusion of human blood remains irreplaceable in human medicine and we need to pave the ground for continued and sustainable action in the decades to come. Blood and transfusion services around the world currently experience challenges and need to increase donor recruitment and retention. This invited commentary focuses on the foundation and maintenance of a functional transfusion service for the coming years as it is imperative to develop and continuously reappraise the blood supply and transfusion service, based on evidence, experience and expertise, to meet expected and unexpected requirements of the future. Several of the greatest national blood and transfusion services in the world lead the way with innovative developments based on research and data from large donor cohorts. This is the context in which, for the last six years, the Oslo Blood Center has scrutinized and reappraised our working processes and use of resources with the aim of increasing the number of active donors. To achieve this objective, we have implemented technological and practical improvements in work processes, donor eligibility, recruitment and donation routines, and launched several projects to increase donor retention.

Effects of storage on quality and function of acid-treated platelets with reduced HLA Class I surface expression.

BACKGROUND: Refractory patients need to be provided with HLA-matched platelets (PLTs), which require time-consuming cross-matching. Treatment of PLTs with citric acid leads to denaturation of the HLA Class I complexes without significant damage to the PLTs. HLA Class I depleted PLTs could alternatively be used to HLA-matched PLTs for transfusion. These PLTs have verified normal function up to 4-6 h after acid treatment. MATERIALS AND METHODS: Buffy coat (BC) PLT concentrates were depleted of HLA Class I complexes by incubation in citric acid. The days after acid-treatment, surface expression of HLA Class I complexes, CD62P and CD63 were determined by flow cytometry, in addition to viability and mitochondrial membrane potential (MMP). Thromboelastography (TEG) tested PLT functionality. RESULTS: Expression of HLA Class I complexes was reduced by 70%-75% in acid-treated PLTs compared to untreated PLTs from day 1 through day 7. Controls and acid-treated PLTs showed insignificant loss of MMP stored for 4 days. Analysis of the residual PLT activation and viability showed no significant differences for 4 days of storage. However, the residual PLT activation potential and viability were significantly decreased in acid-treated PLTs and control PLTs after 7 days of storage. Acid treatment caused a significant decrease in the TEG variable, reaction time (R time), for acid-treated PLTs as compared to control PLTs from days 1 through day 3. CONCLUSION: Our data suggest that extended storage of acid-treated PLTs is possible and will improve flexibility when planning for transfusion of patients with alloimmune PLT refractoriness caused by anti-HLA-antibodies.

Safe Blood Donation from Donors Using Antihypertensive Medication. A Multi-Center Retrospective Quality Study from South-East Norway.

Purpose: In Norway, blood donors using antihypertensive medication were deferred until 2015. Following revision of the national directive, these donors could be allowed, providing stable dose for at least 3 months, adequate blood pressure control and no adverse effects caused by the therapy. The new practice was evaluated by a quality study where the major aim was to establish whether donations from blood donors on antihypertensive medication pose a risk to the donor. The risk was assessed by counting the number and categorizing the adverse events related to blood donation. In addition, the quantitative effect of including these donors was calculated. Subjects and Methods: In this retrospective quality study, blood donors on antihypertensive therapy were recruited from four different blood centers to fill out a questionnaire. A total of 265 donors answered questions regarding their health status, type of medication used, and adverse events connected to blood donation both before and after starting the therapy. Results: No severe adverse events were observed in donors on antihypertensive medications. The amount of mild adverse events, as exhibited by only 7 persons (0.46%) in this donor population, was the same as for donors without hypertensive treatment. Conclusion: Blood donation from persons on antihypertensive therapy poses no extra risk of severe adverse events, given the use of screening criteria to identify and bleed only low-risk donors.

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

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

COVID-19 convalescent plasma from Norwegian blood donors. / Covid-19-rekonvalesensplasma fra norske blodgivere.

The collection and use of convalescent plasma to treat COVID-19 has taught us important lessons about the organisation, testing and selection of blood donors and patients. This is knowledge that can be used in the next pandemic.

Humoral and cellular immune responses to two and three doses of SARS-CoV-2 vaccines in rituximab-treated patients with rheumatoid arthritis: a prospective, cohort study.

BACKGROUND: In rituximab-treated patients with rheumatoid arthritis, humoral and cellular immune responses after two or three doses of SARS-CoV-2 vaccines are not well characterised. We aimed to address this knowledge gap. METHODS: This prospective, cohort study (Nor-vaC) was done at two hospitals in Norway. For this sub-study, we enrolled patients with rheumatoid arthritis on rituximab treatment and healthy controls who received SARS-CoV-2 vaccines according to the Norwegian national vaccination programme. Patients with insufficient serological responses to two doses (antibody to the receptor-binding domain [RBD] of the SARS-CoV-2 spike protein concentration <100 arbitrary units [AU]/mL) were allotted a third vaccine dose. Antibodies to the RBD of the SARS-CoV-2 spike protein were measured in serum 2-4 weeks after the second and third doses. Vaccine-elicited T-cell responses were assessed in vitro using blood samples taken before and 7-10 days after the second dose and 3 weeks after the third dose from a subset of patients by stimulating cryopreserved peripheral blood mononuclear cells with spike protein peptides. The main outcomes were the proportions of participants with serological responses (anti-RBD antibody concentrations of ≥70 AU/mL) and T-cell responses to spike peptides following two and three doses of SARS-CoV-2 vaccines. The study is registered at ClinicalTrials.gov, NCT04798625, and is ongoing. FINDINGS: Between Feb 9, 2021, and May 27, 2021, 90 patients were enrolled, 87 of whom donated serum and were included in our analyses (69 [79·3%] women and 18 [20·7%] men). 1114 healthy controls were included (854 [76·7%] women and 260 [23·3%] men). 49 patients were allotted a third vaccine dose. 19 (21·8%) of 87 patients, compared with 1096 (98·4%) of 1114 healthy controls, had a serological response after two doses (p<0·0001). Time since last rituximab infusion (median 267 days [IQR 222-324] in responders vs 107 days [80-152] in non-responders) and vaccine type (mRNA-1273 vs BNT162b2) were significantly associated with serological response (adjusting for age and sex). After two doses, 10 (53%) of 19 patients had CD4+ T-cell responses and 14 (74%) had CD8+ T-cell responses. A third vaccine dose induced serological responses in eight (16·3%) of 49 patients, but induced CD4+ and CD8+ T-cell responses in all patients assessed (n=12), including responses to the SARS-CoV-2 delta variant (B.1.617.2). Adverse events were reported in 32 (48%) of 67 patients and in 191 (78%) of 244 healthy controls after two doses, with the frequency not increasing after the third dose. There were no serious adverse events or deaths. INTERPRETATION: This study provides important insight into the divergent humoral and cellular responses to two and three doses of SARS-CoV-2 vaccines in rituximab-treated patients with rheumatoid arthritis. A third vaccine dose given 6-9 months after a rituximab infusion might not induce a serological response, but could be considered to boost the cellular immune response. FUNDING: The Coalition for Epidemic Preparedness Innovations, Research Council of Norway Covid, the KG Jebsen Foundation, Oslo University Hospital, the University of Oslo, the South-Eastern Norway Regional Health Authority, Dr Trygve Gythfeldt og frues forskningsfond, the Karin Fossum Foundation, and the Research Foundation at Diakonhjemmet Hospital.

Proteomic study of apheresis platelets made HLA class I deficient for transfusion of refractory patients.

PURPOSE: Refractoriness can occur after repeated platelet (PLT) transfusions because of alloimmunization to HLA class I antigens on transfused PLTs and generation of anti-HLA antibodies that bind to the foreign PLTs and initiate their destruction. Such refractoriness can be overcome by provision of HLA-matched PLTs from HLA typed donors. However, since the procedure is both expensive and time-consuming, an alternative approach is to deplete PLTs of HLA class I molecules by a brief treatment with citric acid, on ice. This is shown to be feasible without damaging PLT function. We used label free quantitative mass spectrometry (MS)-based proteomics to investigate the effect of acid treatment on apheresis PLTs for combatting immunologic PLT refractoriness. EXPERIMENTAL DESIGN: Proteomic analyses are undertaken using PLTs from seven apheresis concentrates, which were split in two with or without acid treatment. RESULTS: In total 1717 proteins in apheresis PLTs were quantified using proteomics. Data are available via ProteomeXchange with identifier PXD027893 . Of these, the amount of 80 proteins changed significantly after acid treatment, but overall there were not any major differences in proteomes between samples with and without acid treatment. CONCLUSIONS AND CLINICAL RELEVANCE: In general, the changes of PLT proteins after treatment with citric acid were quite small and functionally safe. Hence, this result taken together with our previously published data indicates that acid treated PLTs can be used for treatment of patients with PLT refractoriness and opens up for a clinical trial.

Sero-prevalence of SARS-CoV-2 antibodies in blood donors during the third wave of infection in Norway, winter/spring 2021.

Cross-sectional studies of the prevalence of anti-SARS-CoV-2 in representative groups are routinely used for surveillance of public health in Norway. The group of blood donors is easily accessible to provide an estimate over the infection prevalence. Repeated testing of returning donors also generates data about the duration of the antibody response following infection and vaccination. The aim of the current study was to provide updated information about the development of the pandemic in the blood donor population, and to estimate the number of asymptomatic donors visiting the blood center, in an effort to evaluate the measures to prevent virus spreading between donors and staff. In the two main blood banks in the Oslo area, all blood donors were offered antibody testing for a period of three months. Almost 12,000 donors were tested, and the mean weekly prevalence of antibody positive donors due to infection was 2.7 % (varied from 2.1 to 4.0 %). The number of donors presenting following vaccination was 810 (6.9 %). An average of 38 % of the infections had been asymptomatic, and 31 % of the antibody-positive donors were unaware of having been infected. In conclusion, the proportion of blood donors seropositive for anti-SARS-CoV-2 in our blood centers was stable whereas the number of vaccinated blood donors rapidly increased. This indicates that the virus spreading in the third wave of infection in the Oslo area mainly happened in groups underrepresented as blood donors. Health care workers prioritized for early vaccination may be overrepresented in the study period.

The story of an extraordinary year: Challenges and opportunities in responding to Covid-19.

Little more than a year after the first reports of a new coronavirus in Wuhan, China, the world is in the middle of a pandemic that has brought dramatic changes in societies all over the world. This is our story, as seen from the Department of Immunology and Transfusion at Oslo University Hospital (OUH).

HLA class I depletion by citric acid, and irradiation of apheresis platelets for transfusion of refractory patients.

BACKGROUND: Patients can form antibodies to foreign human leukocyte antigen (HLA) Class I antigens after exposure to allogeneic cells. These anti-HLA class I antibodies can bind transfused platelets (PLTs) and mediate their destruction, thus leading to PLT refractoriness. Patients with PLT refractoriness need HLA-matched PLTs, which require expensive HLA typing of donors, antibody analyses of patient sera and/or crossmatching. An alternative approach is to reduce PLT HLA Class I expression using a brief incubation in citric acid on ice at low pH. METHODS AND MATERIALS: Apheresis PLT concentrates were depleted of HLA Class I complexes by 5 minutes incubation in ice-cold citric acid, at pH 3.0. Surface expression of HLA Class I complexes, CD62P, CD63, phosphatidylserine, and complement factor C3c was analyzed by flow cytometry. PLT functionality was tested by thromboelastography (TEG). RESULTS: Acid treatment reduced the expression of HLA Class I complexes by 71% and potential for C3c binding by 11.5-fold compared to untreated PLTs. Acid-treated PLTs were significantly more activated than untreated PLTs, but irrespective of this increase in steady-state activation, CD62P and CD63 were strongly upregulated on both acid-treated and untreated PLTs after stimulation with thrombin receptor agonist peptide. Acid treatment did not induce apoptosis over time. X-ray irradiation did not significantly influence the expression of HLA Class I complexes, CD62P, CD63, and TEG variables on acid treated PLTs. CONCLUSION: The relatively simple acid stripping method can be used with irradiated apheresis PLTs and may prevent transfusion-associated HLA sensitization and overcome PLT refractoriness.

Differential Levels and Phosphorylation of Type 1 Inositol 1,4,5-Trisphosphate Receptor in Four Different Murine Models of Huntington Disease.

BACKGROUND: The intracellular ion channel type 1 inositol 1,4,5-trisphosphate receptor (IP3R1) releases Ca2+ from the endoplasmic reticulum upon stimulation with IP3. Perturbation of IP3R1 has been implicated in the development of several neurodegenerative disorders, including Huntington disease (HD). OBJECTIVE: To elucidate the putative role of IP3R1 phosphorylation in HD, we investigated IP3R1 levels and protein phosphorylation state in the striatum, hippocampus and cerebellum of four murine HD models. METHODS: Quantitative immunoblotting with antibodies to IP3R1 protein and its phosphorylated serines 1589 and 1755 was applied to brain homogenates from R6/1 mice to study early-onset aggressive HD. To determine if IP3R1 changes precede overt pathology, we immunostained tissues from the regions of interest and several control regions for IP3R1 in tgHDCAG51n rats and BACHD and zQ175DNKI mice, all recognized models for late-onset HD. RESULTS: R6/1 mice had reduced total IP3R1 immunoreactivity, variably reduced serine1755-phosphorylation in all regions investigated, and reduced serine1589-phosphorylation in cerebellum. IP3R1 levels were decreased relative to cell-specific marker proteins. In tgHDCAG51n rats we found reduced IP3R1 levels in the cerebellum, but otherwise unchanged IP3R1 phosphorylation and protein levels. In BACHD and zQ175DNKI mice only age-dependent decline of IP3R1 was observed. CONCLUSION: The level and phosphorylation of IP3R1 is reduced to a variable degree in the different HD models relative to control, indicating that earlier findings in more aggressive exon 1-truncated HD models may not be replicated in models with higher construct validity. Further analysis of possible coupling of reduced IP3R1 levels with development of neuropathological responses and cell-specific degeneration is warranted.

Donor health assessment - When is blood donation safe?

Blood donation is a highly regulated practice in the world, ensuring the safety and efficacy of collected blood and its components whether used as irreplaceable parts of modern transfusion medicine, as a therapeutic modality or additional support to other clinical therapies. In Norway blood donation is regulated by governmental regulations ("Blodforskriften") and further instructed by national guidelines, "Veileder for transfusjonstjenesten" [1], providing an aid for assessment of donor health. This concise review touches upon: definitions of donor health and disease; some important pitfalls; and the handling of some common and less common pathophysiological conditions; with an example from the Blood center of Oslo University Hospital, Norway's largest blood center. I also comment on some medications used by a number of blood donors, although wounds, ulcers and surgery are not included. Considering the panorama of conditions blood donors can suffer from, blood donation can never be completely safe for everybody, as zero risk does not exist, but it is our task through donor evaluation to identify and reduce risk as much as possible.

Corrigendum: Protein Kinase C Phosphorylates the System N Glutamine Transporter SN1 (Slc38a3) and Regulates Its Membrane Trafficking and Degradation.

[This corrects the article on p. 138 in vol. 4, PMID: 24106489.].

Paroxysmal nocturnal haemoglobinuria at Oslo University Hospital 2000-2010.

BACKGROUND: Paroxysmal nocturnal haemoglobinuria (PNH) is a rare haematological disease characterised by chronic haemolysis, pancytopenia and venous thrombosis. The condition is attributable to a lack of control of complement attack on erythrocytes, thrombocytes and leukocytes, and can be diagnosed by means of flow cytometry. In this quality assurance study, we have reviewed information from the medical records of all patients tested for PNH using flow cytometry at our laboratory over a ten-year period. MATERIAL AND METHOD: In the period 2000-2010 a total of 28 patients were tested for PNH using flow cytometry at the Department of Immunology and Transfusion Medicine, Oslo University Hospital. We have reviewed the results of these examinations retrospectively together with information from medical records and transfusion data for the patients concerned. RESULTS: Flow cytometry identified 22 patients with PNH: four with classic disease and 18 with PNH secondary to another bone marrow disease. Five patients had atypical thrombosis. Seventeen patients received antithymocyte globulin or drug treatment; of these, six recovered from their bone marrow disease, while six died and five had a need for long-term transfusion. Five patients with life-threatening bone marrow disease underwent allogeneic stem cell transplantation, three of whom died. Six of 22 patients received eculizumab; the need for transfusion has been reduced or eliminated in three patients treated with eculizumab over a longer period. INTERPRETATION: Flow cytometry identified PNH in a majority of patients from whom we obtained samples. Most patients had a PNH clone secondary to bone marrow failure. Atypical thrombosis should be borne in mind as an indication for the test. Treatment with eculizumab is relevant for selected patients with PNH.