RHD-negative red cells may be avoided for patients with ambiguous serologic typing for the RHD antigen

BACKGROUND AND OBJECTIVES

Serologic typing with monoclonal anti-D is mandatory for RHD antigen determination before transfusion, but due to aberrant (weak or partial) variants of RHD, results may be ambiguous and molecular RHD-typing is required. Before that, RHD-negative (RHD -) red blood cells concentrates (RBCs) shall be transfused to avoid anti-D formation, which probably leads to wastage of RHD - RBCs. STUDY DESIGN AND METHODS: All patients with ambiguous results in serologic RHD-typing and molecular RHD-typing were assessed retrospectively. The proportions of patients at risk for anti-D formation and the proportion of RHD - RBCs transfused unnecessarily were evaluated for the following transfusion strategies: (1) RHD-positive (RHD + )RBCs for all patients, (2) RHD + RBCs for patients with at least 2+ reaction with anti-D, (3) RHD + RBCs for patients with C and/or E in their RHCE-phenotype, (4) RHD + RBCs for patients with C and/or E and at least 2+ reaction, and (5) RHD - RBCs for all patients.

RESULTS

A total of 112 patients were included. Most had weak D type 1-3 and a minority had other, rare RHD variants. The risk of anti-D formation was 4.5%, 2.9%, 1.8%, 1.0%, and 0% for strategies 1-5, respectively. The proportion of RHD - RBCs transfused unnecessarily was 0%, 49.5%, 0.9%, 50.5%, and 95.5%.

CONCLUSION

Transfusing patients with a C and/or E in their RHCE-phenotype with RHD + RBCs resulted in a very low risk of immunization while avoiding wastage of RHD - RBCs. Therefore, this strategy should be used for some patients with ambiguous results in serologic RHD-typing and pending results of molecular RHD-typing.

Monitoring the SARS-CoV-2 Pandemic: Prevalence of Antibodies in a Large, Repetitive Cross-Sectional Study of Blood Donors in Germany—Results from the SeBluCo Study 2020–2022

SARS-CoV-2 serosurveillance is important to adapt infection control measures and estimate the degree of underreporting. Blood donor samples can be used as a proxy for the healthy adult population. In a repeated cross-sectional study from April 2020 to April 2021, September 2021, and April/May 2022, 13 blood establishments collected 134,510 anonymised specimens from blood donors in 28 study regions across Germany. These were tested for antibodies against the SARS-CoV-2 spike protein and nucleocapsid, including neutralising capacity. Seroprevalence was adjusted for test performance and sampling and weighted for demographic differences between the sample and the general population. Seroprevalence estimates were compared to notified COVID-19 cases. The overall adjusted SARS-CoV-2 seroprevalence remained below 2% until December 2020 and increased to 18.1% in April 2021, 89.4% in September 2021, and to 100% in April/May 2022. Neutralising capacity was found in 74% of all positive specimens until April 2021 and in 98% in April/May 2022. Our serosurveillance allowed for repeated estimations of underreporting from the early stage of the pandemic onwards. Underreporting ranged between factors 5.1 and 1.1 in the first two waves of the pandemic and remained well below 2 afterwards, indicating an adequate test strategy and notification system in Germany.

Completing the Donor History Questionnaire before the Donation Visit Can Improve Blood Safety

Background and Objectives

In Germany, the donor history questionnaire (DHQ) is traditionally filled in at the donation center to avoid any influence of others. Since March 2020, it has been suggested to donors to answer the DHQ already at home and to call if they have any concerns to reduce the number of ineligible donors on-site during the COVID-19 pandemic.

Materials and Methods

We evaluated the rate of ineligible donors before and after March 2020. Additionally, an anonymous online survey asking for the donors' attitude towards the DHQ was performed. It included questions on whether and for what reason the DHQ had been answered incorrectly in the past.

Results

The rate of ineligible donors decreased by 27% (from 7.1% to 5.2%). In total, 5,556 of 10,252 invited donors completed the survey (54.2%). 88.6% reported either going through the DHQ at home or knowing all questions from their previous donations. 444 donors (8.0%) had at least once postponed a donation after reading the DHQ at home. 68 donors (1.2%) admitted having intentionally provided false answers in the past (9 at home, 43 on-site, 14 both, 2 unknown). Not wanting to be rejected once arriving at the donation center was an important motivation for 42% of donors answering incorrectly on-site. Details on 46 incorrect answers were provided: only 17 had no influence on donor eligibility or product quality. In 5 cases, some blood products might have had impaired quality. Truthful answers to 17 questions would have led to deferral, mostly due to increased risk for unrecognized viral infections transmitted by sexual contacts. For a further 7 questions, there was insufficient information available to determine possible consequences. Asked about their general opinion, 753 (13.6%) of all donors estimated the risk of incorrect answers being greater on-site, while 239 (4.3%) presumed an increased risk at home.

Conclusion

Answering the DHQ prior to a donation visit prevented ineligible donors from visiting the donation center. Furthermore, it might improve honesty, as the discomfort of being deferred after arriving at the donation center was an important reason to answer incorrectly. Overall, there was no increased risk of donor or product safety, and potentially even a benefit.

Differences in Immunogenicity of Three Different Homo- and Heterologous Vaccination Regimens against SARS-CoV-2

Background: Due to findings on adverse reactions and clinical efficacy of different vaccinations against SARS-CoV-2, the administration of vaccination regimens containing both adenoviral vector vaccines and mRNA-based vaccines has become common. Data are still needed on the direct comparison of immunogenicity for these different regimens. Methods: We compared markers for immunogenicity (anti-S1 IgG/IgA, neutralizing antibodies, and T-cell response) with three different vaccination regimens (homologous ChAdOx1 nCoV-19 (n = 103), or mixture of ChAdOx1 nCoV-19 with mRNA-1273 (n = 116) or BNT162b2 (n = 105)) at two time points: the day of the second vaccination as a baseline and 14 days later. Results: All examined vaccination regimens elicited measurable immune responses that were significantly enhanced after the second dose. Homologous ChAdOx1 nCoV-19 was markedly inferior in immunogenicity to all other examined regimens after administration of the second dose. Between the heterologous regimens, mRNA-1273 as second dose induced greater antibody responses than BNT162b2, with no difference found for neutralizing antibodies and T-cell response. Discussion: While these findings allow no prediction about clinical protection, from an immunological point of view, vaccination against SARS-CoV-2 with an mRNA-based vaccine at one or both time points appears preferable to homologous vaccination with ChAdOx1 nCoV-19. Whether or not the demonstrated differences between the heterologous regimens are of clinical significance will be subject to further research.

Kinetics of the Antibody Response to Boostering With Three Different Vaccines Against SARS-CoV-2

Background

Heterologous vaccinations against SARS-CoV-2 with ChAdOx1 nCoV-19 and a second dose of an mRNA-based vaccine have been shown to be more immunogenic than homologous ChAdOx1 nCoV-19. In the current study, we examined the kinetics of the antibody response to the second dose of three different vaccination regimens (homologous ChAdOx1 nCoV-19 vs. ChAdOx1 nCoV-19 + BNT162b2 or mRNA-1273) against SARS-CoV-2 in a longitudinal manner; whether there are differences in latency or amplitude of the early response and which markers are most suitable to detect these responses.

Methods

We performed assays for anti-S1 IgG and IgA, anti-NCP IgG and a surrogate neutralization assay on serum samples collected from 57 participants on the day of the second vaccination as well as the following seven days.

Results

All examined vaccination regimens induced detectable antibody responses within the examined time frame. Both heterologous regimens induced responses earlier and with a higher amplitude than homologous ChAdOx1 nCoV-19. Between the heterologous regimens, amplitudes were somewhat higher for ChAdOx1 nCoV-19 + mRNA-1273. There was no difference in latency between the IgG and IgA responses. Increases in the surrogate neutralization assay were the first changes to be detectable for all regimens and the only significant change seen for homologous ChAdOx1 nCoV-19.

Discussion

Both examined heterologous vaccination regimens are superior in immunogenicity, including the latency of the response, to homologous ChAdOx1 nCoV-19. While the IgA response has a shorter latency than the IgG response after the first dose, no such difference was found after the second dose, implying that both responses are driven by separate plasma cell populations. Early and steep increases in surrogate neutralization levels suggest that this might be a more sensitive marker for antibody responses after vaccination against SARS-CoV-2 than absolute levels of anti-S1 IgG.

Determination of unacceptable HLA antigen mismatches in kidney transplant recipients

With the introduction of the virtual allocation crossmatch in the Eurotransplant (ET) region in 2023, the determination of unacceptable antigen mismatches (UAM) in kidney transplant recipients is of utmost importance for histocompatibility laboratories and transplant centers. Therefore, a joined working group of members from the German Society for Immunogenetics (Deutsche Gesellschaft für Immungenetik, DGI) and the German Transplantation Society (Deutsche Transplantationsgesellschaft, DTG) revised and updated the previous recommendations from 2015 in light of recently published evidence. Like in the previous version, a wide range of topics is covered from technical issues to clinical risk factors. This review summarizes the evidence about the prognostic value of contemporary methods for HLA antibody detection and identification, as well as the impact of UAM on waiting time, on which these recommendations are based. As no clear criteria could be determined to differentiate potentially harmful from harmless HLA antibodies, the general recommendation is to assign all HLA against which plausible antibodies are found as UAM. There is, however, a need for individualized solutions for highly immunized patients. These revised recommendations provide a list of aspects that need to be considered when assigning UAM to enable a fair and comprehensible procedure and to harmonize risk stratification prior to kidney transplantation between transplant centers. This article is protected by copyright. All rights reserved.

Headache Attributed to Vaccination Against COVID-19 (Coronavirus SARS-CoV-2) with the ChAdOx1 nCoV-19 (AZD1222) Vaccine: A Multicenter Observational Cohort Study

INTRODUCTION

The most frequently reported neurological adverse event of ChAdOx1 nCoV-19 (AZD1222) vaccine is headache in 57.5%. Several cases of cerebral venous thrombosis (CVT) have developed after vaccination. Headache is the leading symptom of CVT. For the differential diagnosis of headaches attributed to this vaccine and headaches attributed to CVT, it is of central clinical importance whether and, if so, how the phenotypes and course of these headaches can be differentiated. The study aims to examine in detail the phenotype of headache attributed to this vaccine.

METHODS

Data on the clinical features and corresponding variables were recorded using a standardized online questionnaire in this multicenter observational cohort study. The primary outcomes of this study are the clinical features of headaches after vaccination.

FINDINGS

A total of 2464 participants reported headaches after vaccination with the ChAdOx1 nCoV-19 (AZD1222) vaccine. On average, headaches occurred 14.5 ± 21.6 h after vaccination and lasted 16.3 ± 30.4 h. A bilateral location was described by 75.8% of participants. This is most often found on the forehead (40.0%) and temples (31.4%); 50.4% reported a pressing and 37.7% a dull pain character. Headache intensity was most often severe (38.7%), moderate (35.2%), or very severe (15.5%). Accompanying symptoms were most commonly fatigue (44.8%), chills (36.1%), exhaustion (34.9%), and fever (30.4%).

CONCLUSION

Headaches attributed to COVID-19 vaccination with the ChAdOx1 nCoV-19 (AZD1222) vaccine demonstrate an extensive and characteristic complex of symptoms. The findings have several important clinical implications for the differentiation of post-vaccinal headache and other primary as well as secondary headaches.

Live Birth Rates after Active Immunization with Partner Lymphocytes

Although many potential causes have been established for recurrent implantation failure (RIF) and recurrent miscarriage (RM), about 50% of these remain idiopathic. Scientific research is focused on immunological risk factors. In the present study, we aim to evaluate live birth rates after immunization with paternal lymphocytes (lymphocyte immunotherapy (LIT)). This retrospective study consisted of 148 couples with a history of RM and/or RIF. The women underwent immunization with lymphocytes of their respective partners from November 2017 to August 2019. Fifty-five patients (43%) had live births. Stratified by indication (RM, RIF, combined), live birth rates in the RM and the combined group were significantly higher than that in the RIF group (53%, 59% and 33%, respectively, p = 0.02). The difference was especially noticeable during the first 90 days after immunization (conception rate leading to live births: 31%, 23% and 8% for RM, the combined group and RIF, respectively; p = 0.005), while there was no difference between groups during the later follow-up. LIT was associated with high live birth rates, especially in women with recurrent miscarriage. In view of the limited data from randomized studies, LIT cannot be recommended as routine therapy. However, it may be considered in individual cases.

Clinical characteristics of headache after vaccination against COVID-19 (coronavirus SARS-CoV-2) with the BNT162b2 mRNA vaccine: a multicentre observational cohort study

The novel coronavirus SARS-CoV-2 causes the infectious disease COVID-19. Newly developed mRNA vaccines can prevent the spread of the virus. Headache is the most common neurological symptom in over 50% of those vaccinated. Detailed information about the clinical characteristics of this form of headache has not yet been described. The aim of the study is to examine in detail the clinical characteristics of headaches occurring after vaccination against COVID-19 with the BNT162b2 mRNA COVID-19 vaccine for the first time. In a multicentre observational cohort study, data on the clinical features and corresponding variables were recorded using a standardized online questionnaire. The questionnaire was circulated to 12 000 residential care homes of the elderly as well as tertiary university hospitals in Germany and the United Arab Emirates. The primary outcomes of this study are the clinical features of headache after vaccination. Comorbidities, treatment with medication and sociodemographic variables are also analysed. A total of 2349 participants reported headaches after vaccination with the BNT162b2 mRNA COVID-19 vaccine. Headaches occur an average of 18.0 ± 27.0 h after vaccination and last an average duration of 14.2 ± 21.3 h. Only 9.7% of those affected also report headaches resulting from previous vaccinations. In 66.6% of the participants, headache occurs as a single episode. A bilateral location is indicated by 73.1% of the participants. This is most often found on the forehead (38.0%) and temples (32.1%). A pressing pain character is indicated by 49.2% and 40.7% report a dull pain character. The pain intensity is most often moderate (46.2%), severe (32.1%) or very severe (8.2%). The most common accompanying symptoms are fatigue (38.8%), exhaustion (25.7%) and muscle pain (23.4%). Headaches after COVID-19 vaccination show an extensive complex of symptoms. The constellation of accompanying symptoms together with the temporal and spatial headache characteristics delimit a distinctive headache phenotype.

Appearance of new CDC-reactive antibodies in patients waiting for kidney transplantation

BACKGROUND

Patients awaiting kidney transplantation are regularly screened for HLA-antibodies, but there is scarce data about the optimal interval.

METHODS

Results from Complement-dependent cytotoxicity testing (CDC) for waitlisted patients were reviewed for increases in panel reactive antibodies (PRA) by at least 10%-points. Clinical records were screened for historic immunizing events and possible trigger factors preceding the PRA-increase. Additionally, non-pretransplanted men tested negative for HLA antibodies by solid-phase assays (SPA) out of their first two samples on the waiting list ("non-immunized men") were evaluated for detection of HLA antibodies by SPA during their further stay on the waiting list.

RESULTS

15,360 samples from 1928 patients tested by CDC were analyzed for changes in PRA. PRA-increases occurred most frequently in patients waitlisted recently for retransplantation (annual incidence 6%). Removal of previous transplants, severe infections and/or reduced immunosuppression triggered 65% of PRA-increases during the first year after waitlisting. Transfusions accounted for 55% of PRA-increases in later years. Leucocyte-reduced red blood cell units not only boosted historic antibodies, but even induced primary immunization. In the second part of the study, 6780 samples tested by SPA from 703 non-immunized men were evaluated for development of HLA-antibodies. Only 9 men (1.3%) turned HLA antibody-positive (annual incidence 0.4%).

CONCLUSION

A uniform screening interval does not fit all: Frequencies should be highest in patients newly waitlisted for re-transplant and lowest in non-immunized men. Transfused patients should be monitored closely for development of HLA-antibodies even if leukoreduced products are used.

Yap regulates skeletal muscle fatty acid oxidation and adiposity in metabolic disease

Obesity is a major risk factor underlying the development of metabolic disease and a growing public health concern globally. Strategies to promote skeletal muscle metabolism can be effective to limit the progression of metabolic disease. Here, we demonstrate that the levels of the Hippo pathway transcriptional co-activator YAP are decreased in muscle biopsies from obese, insulin-resistant humans and mice. Targeted disruption of Yap in adult skeletal muscle resulted in incomplete oxidation of fatty acids and lipotoxicity. Integrated 'omics analysis from isolated adult muscle nuclei revealed that Yap regulates a transcriptional profile associated with metabolic substrate utilisation. In line with these findings, increasing Yap abundance in the striated muscle of obese (db/db) mice enhanced energy expenditure and attenuated adiposity. Our results demonstrate a vital role for Yap as a mediator of skeletal muscle metabolism. Strategies to enhance Yap activity in skeletal muscle warrant consideration as part of comprehensive approaches to treat metabolic disease.

Bestrahlung zellulärer Blutprodukte – Änderungen in den neuen Querschnitts-Leitlinien

Die transfusionsassoziierte Graft-versus-Host-Erkrankung (ta-GvHD) ist eine seltene, aber lebensbedrohliche Nebenwirkung der Transfusion zellulärer Blutprodukte, die durch restliche Lymphozyten des Blutspenders hervorgerufen wird. Risikofaktoren für eine ta-GvHD sind eine geschwächte T-zelluläre Abwehr des Patienten, eine hohe Zahl residueller Lymphozyten im Blutprodukt und eine einseitige HLA-Inkompatibilität zwischen Spender und Empfänger. Durch eine Bestrahlung zellulärer Blutkomponenten mit mindestens 25 Gray lässt sich eine ta-GvHD sicher verhindern. In der gerade erschienenen 5. Auflage der Querschnitts-Leitlinien der Bundesärztekammer zur Therapie mit Blutkomponenten und Plasmaderivaten wurden einige Indikationen zur Bestrahlung gelockert, da Erfahrungen aus Großbritannien zeigen, dass hier auch nach Transfusion unbestrahlter Blutprodukte kein Risiko für eine ta-GvHD besteht. So stellen lymphatische Neoplasien nicht mehr generell eine Bestrahlungsindikation dar, sondern nur, wenn ein Hodgkin-Lymphom oder ein schwerer T-Zell-Defekt vorliegt oder wenn bestimmte Therapien durchgeführt werden bzw. wurden (z. B. Gabe von Purinanaloga). Zu anderen Indikationen finden sich in den revidierten Querschnitts-Leitlinien erstmals Empfehlungen zur Verwendung bestrahlter Blutkomponenten: Dies betrifft z. B. hämatoonkologische Patienten unter Therapie mit ATG oder Alemtuzumab. Der Artikel fasst den aktuellen Erkenntnisstand zur ta-GvHD kurz zusammen und erläutert die Änderungen der revidierten Querschnitts-Leitlinien.

Pre-transplant HLA Antibodies and Delayed Graft Function in the Current Era of Kidney Transplantation

Delayed graft function (DGF) occurs in a significant proportion of deceased donor kidney transplant recipients and was associated with graft injury and inferior clinical outcome. The aim of the present multi-center study was to identify the immunological and non-immunological predictors of DGF and to determine its influence on outcome in the presence and absence of human leukocyte antigen (HLA) antibodies. 1,724 patients who received a deceased donor kidney transplant during 2008–2017 and on whom a pre-transplant serum sample was available were studied. Graft survival during the first 3 post-transplant years was analyzed by multivariable Cox regression. Pre-transplant predictors of DGF and influence of DGF and pre-transplant HLA antibodies on biopsy-proven rejections in the first 3 post-transplant months were determined by multivariable logistic regression. Donor age ≥50 years, simultaneous pre-transplant presence of HLA class I and II antibodies, diabetes mellitus as cause of end-stage renal disease, cold ischemia time ≥18 h, and time on dialysis >5 years were associated with increased risk of DGF, while the risk was reduced if gender of donor or recipient was female or the reason for death of donor was trauma. DGF alone doubled the risk for graft loss, more due to impaired death-censored graft than patient survival. In DGF patients, the risk of death-censored graft loss increased further if HLA antibodies (hazard ratio HR=4.75, P < 0.001) or donor-specific HLA antibodies (DSA, HR=7.39, P < 0.001) were present pre-transplant. In the presence of HLA antibodies or DSA, the incidence of biopsy-proven rejections, including antibody-mediated rejections, increased significantly in patients with as well as without DGF. Recipients without DGF and without biopsy-proven rejections during the first 3 months had the highest fraction of patients with good kidney function at year 1, whereas patients with both DGF and rejection showed the lowest rate of good kidney function, especially when organs from ≥65-year-old donors were used. In this new era of transplantation, besides non-immunological factors, also the pre-transplant presence of HLA class I and II antibodies increase the risk of DGF. Measures to prevent the strong negative impact of DGF on outcome are necessary, especially during organ allocation for presensitized patients.

P1646SURVIVAL OF KIDNEY TRANSPLANTS ACCORDING TO PRESENCE OF HLA ANTIBODIES WHEN DONORSPECIFIC ANTIBODIES ARE SCREENED DURING POSTTRANSPLANT FOLLOW-UP

Background and Aims

Posttransplant kidney survival depends on several risk factors. A careful immunogenetic matching and the absence of HLA donor specific antibodies (DSA) seem to determine the longevity of the transplant.

Method

Screening the presence of donor specific HLA antibodies in our posttransplant outpatients was implemented in 2010 (every 6 months in case of DSA free patients for two years, then yearly, and every 3 months in case of DSA + patients for two years, then twice a year). At the same time a treatment protocol was implemented, omitting reduction of immunosuppressive drugs in case of newly detected DSA, and most important with preventing steroid withdrawal in this case.The present single center study reports the long-term survival and kidney function from patients undergoing HLA-screening after transplantation between 2010 and 2016 with a follow-up until 2018. Using a Kaplan-Meier analysis patients without HLA antibodies (no HLA-ab), with HLA antibodies but without DSA (NDSA), and with donor-specific HLA antibodies (DSA) were compared by logrank-testing.

Results

A full dataset was obtained from 318 patients. The mean overall survival (patients and organ function) didn´t differ between the three groups, p=0.318: no HLA-ab 7.2 years (95%confidence interval 6.7;7.6), NDSA 6.6 (5.9;7.2), DSA 6.8 (6.1;7.5), overall 7.0 (6.6;7.3), events are given in Table1. Whereas the mean patient survival didn´t differ between the groups (p=0.715), the mean death-censored graft survival differed significantly, p=0.008, with a reduced transplant survival in the patients with HLA antibodies but without donorspecific antibodies: no HLA-ab 8.0 years (95%confidence interval 7.7;8.3), NDSA 7.0 (6.4;7.6), DSA 7.6 (7.1;8.2), overall 7.7 (7.4;8.0), numbers are given in Table1.

Conclusion

In conclusion, the presence of HLA antibodies was associated with a reduced transplant survival. Patients with HLA antibodies had a worse survival than patients with DSA undergoing HLA screening with a personalised immunosuppressive regimen. Immunosuppressive regimen of the groups, as well as other known risk factors of graft survival have to be further analysed. The results of these multivariate analyses have to be awaited to determine whether the risk for graft loss inferred by HLA antibodies is independent from other factors.

1183Beta-Adrenoceptor activation increases cardiac galectin-3 levels via the hippo signaling pathway

Background

Galectin-3 (Gal-3) is a clinical biomarker for risk of cardiovascular disease and a disease mediator forming a therapeutic target. However, the mechanism(s) that regulate cardiac expression of Gal-3 remains unknown. Activation of the sympatho-β-adrenergic system is a hallmark of heart disease, but the relationship of βAR activation and cardiac content of Gal-3 remains unknown.

Purpose

To determine the role of βAR activation in regulating cardiac Gal-3 level and the responsible mechanism focusing on the Hippo signalling pathway.

Methods

Wild-type and Gal-3 gene deleted (Gal3-KO) mice were used. To test the role of the Hippo pathway, we used transgenic (TG) mouse strains with cardiac overexpression of mammalian-20-like sterile kinase 1 (Mst1, mammalian orthology of Drosophila Hippo kinase) either in wild-type form (TG-Mst1) or dominative-negative kinase dead mutant form (TG-dnMst1). Effects of β-antagonist (isoprenaline, ISO) and antagonists were determined. We measured phosphorylation (Ser127) of YAP as a transcription co-regulator acting as the main signal output of the Hippo pathway.

Results

In wild-type mice, treatment with ISO led to a time- and dose-dependent increase in cardiac expression of Gal-3 (Fig. A) accompanied by elevated circulating Gal-3 levels (Fig. B). ISO treatment stimulated cardiac expression of Mst1 and YAP hyper-phosphorylation (i.e. inactivation, Fig. C), indicating activation of the Hippo signalling. These effects of ISO were inhibited by β-blockers (propranolol, Prop; carvedilol, Carv; Fig. D,E). Relative to non-TG controls, ISO-induced expression of Gal-3 was inhibited by 75% in TG-dnMst1 mice (inactivated Mst1), but exaggerated by 7-fold in TG-Mst1 mice (activated Mst1). Mst1-TG mice had a 45-fold increase in Gal-3 content, YAP hyper-phosphorylation and enhanced pro-fibrotic signaling. In Mst1-TG mice, whilst blood Gal-3 level was unchanged, treatment with ISO (6 mg, 2 days) evoked a marked increase in cardiac and blood Gal-3 levels. Using rat cardiomyoblasts, we showed that ISO-mediated Mst1 expression and YAP phosphorylation were PKA-dependent and that siRNA-mediated YAP knockdown led to Gal-3 upregulation. The role of Gal-3 in mediating ISO-induced cardiomyopathy was examined by treating wild-type and Gal3-KO mice with ISO (30 mg/kg, 7 days). ISO-treated wild-type mice had 8-fold increase in cardiac Gal-3, ventricular dysfunction, fibrosis, hypertrophy and activated inflammatory or fibrotic signalling. All these changes, except hypertrophy, were abolished by Gal3-KO.

beta-AR regulates galectin-3

Conclusion

βAR stimulation increases cardiac expression of Gal-3 through activation of the Hippo signalling pathway. This is accompanied by elevated circulating Gal-3 level. βAR antagonists inhibited βAR-Mst1 (Hippo) signalling and cardiac Gal-3 expression, actions likely contributing to the overall efficacy of β-blockers.

Acknowledgement/Funding

NHMRC of Australia; Nature Science Fund of China

Preformed Donor-Specific HLA Antibodies in Living and Deceased Donor Transplantation: A Multicenter Study

BACKGROUND AND OBJECTIVES

The prognostic value of preformed donor-specific HLA antibodies (DSA), which are only detectable by sensitive methods, remains controversial for kidney transplantation.

DESIGN, SETTING, PARTICIPANTS, & MEASUREMENTS

The outcome of 4233 consecutive kidney transplants performed between 2012 and 2015 in 18 German transplant centers was evaluated. Most centers used a stepwise pretransplant antibody screening with bead array tests and differentiation of positive samples by single antigen assays. Using these screening results, DSA against HLA-A, -B, -C, -DRB1 and -DQB1 were determined. Data on clinical outcome and possible covariates were collected retrospectively.

RESULTS

Pretransplant DSA were associated with lower overall graft survival, with a hazard ratio of 2.53 for living donation (95% confidence interval [95% CI], 1.49 to 4.29; P<0.001) and 1.59 for deceased donation (95% CI, 1.21 to 2.11; P=0.001). ABO-incompatible transplantation was associated with worse graft survival (hazard ratio, 2.09; 95% CI, 1.33 to 3.27; P=0.001) independent from DSA. There was no difference between DSA against class 1, class 2, or both. Stratification into DSA <3000 medium fluorescence intensity (MFI) and DSA ≥3000 MFI resulted in overlapping survival curves. Therefore, separate analyses were performed for 3-month and long-term graft survival. Although DSA <3000 MFI tended to be associated with both lower 3-month and long-term transplant survival in deceased donation, DSA ≥3000 MFI were only associated with worse long-term transplant survival in deceased donation. In living donation, only strong DSA were associated with reduced graft survival in the first 3 months, but both weak and strong DSA were associated with reduced long-term graft survival. A higher incidence of antibody-mediated rejection within 6 months was only associated with DSA ≥3000 MFI.

CONCLUSIONS

Preformed DSA were associated with an increased risk for graft loss in kidney transplantation, which was greater in living than in deceased donation. Even weak DSA <3000 MFI were associated with worse graft survival. This association was stronger in living than deceased donation.

Anti-HLA alloantibodies of the IgA isotype in re-transplant candidates part II: Correlation with graft survival

We reported previously on the widespread occurrence of anti-HLA alloantibodies of the IgA isotype (anti-HLA IgA) in the sera of solid-organ re-transplantation (re-tx) candidates (Arnold et al., ). Specifically focussing on kidney re-tx patients, we now extended our earlier findings by examining the impact of the presence and donor specificity of anti-HLA IgA on graft survival. We observed frequent concurrence of anti-HLA IgA and anti-HLA IgG in 27% of our multicenter collective of 694 kidney re-tx patients. This subgroup displayed significantly reduced graft survival as evidenced by the median time to first dialysis after transplantation (TTD 77 months) compared to patients carrying either anti-HLA IgG or IgA (TTD 102 and 94 months, respectively). In addition, donor specificity of anti-HLA IgA had a significant negative impact on graft survival (TTD 74 months) in our study. Taken together, our data strongly indicate that presence of anti-HLA IgA, in particular in conjunction with anti-HLA-IgG, in sera of kidney re-tx patients is associated with negative transplantation outcome.

Active Immunisation with Partner Lymphocytes in Female Patients Who Want to Become Pregnant - Current Status

Around 1 – 3% of all couples who try to have a child are affected by recurrent miscarriage. According to the WHO, recurrent miscarriage is defined as the occurrence of three or more consecutive miscarriages up to the 20th week of pregnancy. There are various causes of recurrent miscarriage; in many cases, the causes remain unclear, with the result that immunological factors are one of the possible causes discussed. For the motherʼs immune system, the embryo represents a semi-allogeneic transplant, as half of the embryoʼs genes are of paternal origin. In place of a conventional immune response, the embryo induces a secondary protection mechanism, which contributes to the successful implantation. When performing immunisation with partner lymphocytes, the patient receives an intradermal injection of her partnerʼs prepared lymphocytes into the volar side of the forearm in order to induce immunomodulation with a consequently increased rate of pregnancy and live birth. A prerequisite for this procedure is that all other possible causes of sterility have been ruled out in advance. Due to the highly heterogeneous nature of the data, a significant benefit as a result of the immunisation cannot yet be clearly proven. However, there are signs that the therapy may be effective when using lymphocytes that have been extracted as short a time beforehand as possible. Overall, the treatment represents a safe, low-risk procedure. Following a detailed informative discussion with the couple regarding the chances of success and following a detailed review of the indication and contraindications, immunisation with partner lymphocytes can be discussed with the couple on a case-by-case basis – provided that all other possible causes of sterility have been ruled out in advance.

Transfusion-transmitted CMV infection - current knowledge and future perspectives

Transmission of human cytomegalovirus (CMV) via transfusion (TT-CMV) may still occur and remains a challenge in the treatment of immunocompromised CMV-seronegative patients, e.g. after stem cell transplantation, and for low birthweight infants. Measures to reduce the risk of TT-CMV have been evaluated in clinical studies, including leucocyte depletion of cellular blood products and/or the selection of CMV-IgG-negative donations. Studies in large blood donor cohorts indicate that donations from newly CMV-IgG-positive donors should bear the highest risk for transmitting CMV infections because they contain the highest levels of CMV-DNA, and early CMV antibodies cannot neutralise CMV. Based on this knowledge, rational strategies to reduce the residual risk of TT-CMV using leucoreduced blood products could be designed. However, there is a lack of evidence that CMV is still transmitted by transfusion of leucoreduced units. In low birthweight infants, most (if not all) CMV infections are caused by breast milk feeding or congenital transmission rather than by transfusion of leucoreduced blood products. For other patients at risk, no definitive data exist about the relative importance of alternative transmission routes of CMV compared to blood transfusion. As a result, only the conduction of well-designed studies addressing strategies to prevent TT-CMV and the thorough examination of presumed cases of TT-CMV will achieve guidance for the best transfusion regimen in patients at risk.

Development of a high-resolution NGS-based HLA-typing and analysis pipeline

The human leukocyte antigen (HLA) complex contains the most polymorphic genes in the human genome. The classical HLA class I and II genes define the specificity of adaptive immune responses. Genetic variation at the HLA genes is associated with susceptibility to autoimmune and infectious diseases and plays a major role in transplantation medicine and immunology. Currently, the HLA genes are characterized using Sanger- or next-generation sequencing (NGS) of a limited amplicon repertoire or labeled oligonucleotides for allele-specific sequences. High-quality NGS-based methods are in proprietary use and not publicly available. Here, we introduce the first highly automated open-kit/open-source HLA-typing method for NGS. The method employs in-solution targeted capturing of the classical class I (HLA-A, HLA-B, HLA-C) and class II HLA genes (HLA-DRB1, HLA-DQA1, HLA-DQB1, HLA-DPA1, HLA-DPB1). The calling algorithm allows for highly confident allele-calling to three-field resolution (cDNA nucleotide variants). The method was validated on 357 commercially available DNA samples with known HLA alleles obtained by classical typing. Our results showed on average an accurate allele call rate of 0.99 in a fully automated manner, identifying also errors in the reference data. Finally, our method provides the flexibility to add further enrichment target regions.

Prevention of Transfusion-Transmitted Cytomegalovirus Infections: Which is the Optimal Strategy?

Traditionally, leukoreduction and selection of blood products from seronegative donors have been used as alternative strategies to reduce the risk of transfusion-transmitted cytomegalovirus infections (TT-CMV) in atrisk patients. After the introduction of universal leukoreduction for red blood cell and platelet concentrates in Germany, a controversy evolved as to whether the additional selection of blood products from seronegative donors would reduce or even increase the risk of TT-CMV. This review summarizes the current knowledge about CMV infections in blood donors and the implications of this information on the effect of potential transfusion strategies. Even though there are conflicting data about the incidence of TT-CMV remaining after the introduction of leukodepletion, it has been clearly shown that both prevalence and concentration of CMV DNA in peripheral blood are highest in newly seropositive donors. Therefore, avoidance of blood products from these donors is the most important goal of any transfusion strategy. This goal can be reached by: i) selection of blood products from seronegative donors, ii) provision of CMV DNA-negative blood products, or iii) provision of blood from long-term seropositive donors. In cases of suspected TT-CMV, all implicated donors should be investigated carefully to gather further knowledge on which donors confer the lowest risk for TT-CMV.

The impact of donor cytomegalovirus DNA on transfusion strategies for at-risk patients

BACKGROUND

Cytomegalovirus (CMV) DNA is frequently detected in plasma of newly seropositive donors. Selection of leukoreduced blood products from donors with remote CMV infection could avoid transfusion-transmitted CMV infections (TT-CMV) due to primarily infected donors. However, there are no data about the prevalence of reactivations in long-term seropositive donors compared to the incidence of window period donations in seronegative donors. Therefore, the optimal transfusion strategy for at-risk patients is unclear.

STUDY DESIGN AND METHODS

Whole blood samples from 22,904 donations were tested for CMV DNA, and CMV DNA-positive donations were categorized as donations from 1) seronegative donors, 2) newly seropositive donors, and 3) long-term seropositive donors.

RESULTS

Twenty-one donors were reproducibly CMV DNA-positive (0.09%). Frequency of detection and concentration of CMV DNA in whole blood were comparable for seronegative and long-term seropositive donors. Nonreproducibly positive results for CMV DNA in whole blood were more frequent in long-term seropositive donors (0.16% vs. 0.01%, p<0.01). Only low concentrations of CMV DNA in plasma were detectable in two seronegative donors and one long-term seropositive donor. Highest concentrations of CMV DNA in both whole blood and plasma, however, were found in newly seropositive donors.

CONCLUSION

Prevalences of window period donations among seronegative donors and reactivations among long-term seropositive donors, as well as the CMV DNA concentration in whole blood and plasma samples from these donors, are comparable. Therefore, blood products from both groups could be used for patients at risk for TT-CMV, while those of newly seropositive donors seem to bear an increased risk.

16(th) IHIW: anti-HLA alloantibodies of the of IgA isotype in re-transplant candidates

In this multicentre study, sera from 803 retransplant candidates, including 775 kidney transplant recipients, were analysed with regard to the presence and specificity of anti-HLA alloantibodies of the IgA isotype using a modified microsphere-based platform. Of the kidney recipients, nearly one-third (n = 237, 31%) had IgA alloantibodies. Mostly, these antibodies were found in sera that also harboured IgG alloantibodies that could be found in a total of 572 (74%) of patients. Interestingly, IgA anti-HLA antibodies were preferentially targeting HLA class I antigens in contrast to those of the IgG isotype, which targeted mostly both HLA class I and II antigens. Donor specificity of the IgA alloantibodies could be established for over half of the 237 patients with IgA alloantibodies (n = 124, 52%). A further 58 patients had specificities against HLA-C or HLA-DP, for which no information regarding donor typing was available. In summary, these data showed in a large cohort of retransplant candidates that IgA alloantibodies occur in about one-third of patients, about half of these antibodies being donor specific.

A novel set of real-time PCRs for rapid differentiation between human cytomegalovirus wild-type and highly passaged laboratory strains

Restricting amplification of human cytomegalovirus (HCMV) DNA to wild-type (WT) HCMV is useful to exclude PCR contaminations by laboratory strains from viral cultures. A set of UL141-specific TaqMan PCRs was developed to amplify (1) WT HCMV and laboratory strain Towne(long), but not strain AD169, (2) only WT HCMV. The performance was compared to a PCR targeting the conserved sequence of HCMV glycoprotein B using 46 serum and urine samples from blood donors with primary CMV infection. Amplification was restricted to the targeted strains with the exception of Towne(long) being amplified also by PCR (2), but at a distinctly lower efficiency than WT HCMV. The coefficient of regression for linear dilutions of two clinical samples with a high concentration of HCMV DNA was 0.999 and 0.997, respectively. The correlation between both WT PCRs and the generic HCMV PCR was good, with coefficients of regression of 0.891 and 0.871 for PCR (1) and (2), respectively. The limit of detection was calculated to be 1.5 genome equivalents per PCR. The set of HCMV TaqMan PCRs enables rapid differentiation between WT and laboratory strains, which can be especially useful as even virus lysate can contaminate sensitive PCRs without prior DNA isolation. A standardized WT HCMV control would be useful to evaluate WT-specific PCR methods.

The natural course of primary cytomegalovirus infection in blood donors

BACKGROUND AND OBJECTIVES

As cytomegalovirus (CMV) DNA is frequently detectable in the plasma of recently infected sero-positive blood donors, information concerning primary CMV infection is important for the identification of possibly infectious donors.

MATERIALS AND METHODS

Monitoring of 17 982 donors for CMV antibodies and DNA in plasma identified 14 subjects with ongoing primary CMV infection. Thirteen donors were interrogated for possible sources of infection and CMV-related symptoms, and monitored for CMV antigens, CMV DNA in plasma, leucocytes and urine, course of IgG and IgM antibodies as well as markers of systemic infection and parameters of organ function.

RESULTS

CMV antigens and DNA were detectable in peripheral blood for up to 54 and 269 days respectively. Clearance of CMV DNA from blood correlated with clearance of IgM antibodies, development of IgG antibodies against the membrane glycoprotein gB and development of high avidity IgG antibodies. Eighty-five percent of subjects with primary CMV infection, but even 69% of matched controls reported possibly CMV-related symptoms. Sixty-two and 23%, respectively, had contact with possible sources of infection. One donor developed a febrile illness accompanied by increased levels of CMV DNA in peripheral blood 2 to 3 weeks after seroconversion. In other donors, neither markers of systemic infection nor parameters of organ function correlated with the course of CMV DNA and antigens.

CONCLUSION

Potentially infectious donors can be identified by measuring CMV DNA, IgM antibodies or avidity of IgG antibodies. Alternatively, blood products donated during the first year after seroconversion should not be used for immunocompromised patients.

Origin and diversification of land plant CC-type glutaredoxins

Glutaredoxins (GRXs) are ubiquitous glutathione-dependent oxidoreductase enzymes implicated in redox homeostasis, particularly oxidative stress response. Three major classes of GRX genes exist, the CPYC, CGFS classes are present in all pro- and eukaryote species, whereas the CC-type class GRXs are specific to land plants. In the basal land plant Physcomitrella patens, only two CC-type GRXs are present, compared with 21 in Arabidopsis. In contrast, sizes of the CPYC and CGFS classes remained rather similar throughout plant evolution, raising the interesting question as to when the CC-type GRXs first originated and how and why they expanded during land plant evolution. Recent evidence suggests that CC-type GRXs may have been recruited during evolution into diverse plant-specific functions of flower development (ROXY1, ROXY2) and pathogenesis response (ROXY19/GRX480). In the present study, GRX genes from the genomes of a range of green algae and evolutionarily diverse land plant species were identified; Ostreococcus, Micromonas, Volvox, Selaginella, Vitis, Sorghum, and Brachypodium. Previously identified sequences from Chlamydomonas, Physcomitrella, Oryza, Arabidopsis, and Populus were integrated to generate a more comprehensive understanding of the forces behind the evolution of various GRX classes. The analysis indicates that the CC-type GRXs probably arose by diversification from the CPYC class, at a time coinciding with colonization of land by plants. This strong differential expansion of the CC-type class occurred exclusively in the angiosperms, mainly through paleopolyploidy duplication events shortly after the monocot–eudicot split, and more recently through multiple tandem duplications that occurred independently in five investigated angiosperm lineages. The presented data suggest that following duplications, subfunctionalization, and subsequent neofunctionalization likely facilitated the sequestration of land plant-specific CC-type GRXs into novel functions such as development and pathogenesis response.

Selection of whole-blood donors for hemoglobin testing by use of historical hemoglobin values

BACKGROUND

Usually, a predonation hemoglobin (Hb) measurement must precede blood donation. Hb values of a donor's previous donation might be used for selecting a subgroup in which predonation Hb measurements are unnecessary.

STUDY DESIGN AND METHODS

Only donors with historical Hb values below 129 or 139 g per L for female and male donors, respectively, underwent venous Hb measurement before phlebotomy with an automated hematology analyzer. All other donor phlebotomies were collected without initial Hb testing. Hb values from diversion samples from 81,913 consecutive donors between May 2003 and November 2005 were subsequently analyzed as representing their present values. Donors were grouped according to interdonation intervals of less than 6, 6 to 11, 12 to 23, and 24 months or more.

RESULTS

The arithmetic mean deviation between historical and present Hb values was between -0.3 and +1.8 g per L for each group (mean deviation, 5.2-6.7 g/L). Not testing selected donors spared 77.7 percent from a prephlebotomy Hb measurement and showed a specificity of 29 percent. Sensitivities for detection of donors below Hb limits (between 56% and 67% for the different subgroups) and donors with Hb values below 110 g per L (82%-88%) were at least comparable to capillary Hb screening. A total of 4.8 percent of donors were phlebotomized with values below 125 and 135 g per L, whereas only 0.016 percent of donors were bled despite Hb levels below 110 g per L.

CONCLUSION

Selecting donors for a current Hb measurement based upon their last whole-blood predonation Hb value is a useful method, even after prolonged interdonation intervals.

Updated audit database for breast imaging/histopathology correlation

AIM

To develop, test and validate an audit database, evolved from a prior, peer-reviewed, audit tool for symptomatic multi-modality breast imaging services.

MATERIALS AND METHODS

The database is to cover all aspects of non-invasive breast imaging and recognize subspeciality inputs. When more than one imaging investigation is used for diagnosis, an overall breast imaging audit grade is to be introduced. Data derived from clinical studies has been input into the new database.

RESULTS

Results for mammography alone are virtually identical to those of the previous program. A slight increase in accuracy is suggested by using more investigations if the first investigation is not conclusive. More comprehensive reports can be issued.

CONCLUSION

The audit program can be used in the same context as the old audit. If mammography is the sole investigation, there is no change from the previous standards of a minimum mammography (ultrasound)/histopathology agreement of 70%, an equivocal rate of less than 15%, a false-positive rate of less than 7.5% and a false-negative rate of less than 6.5%. Although there is no statistical difference when more than one imaging investigation is used, there is some marginal improvement. It is suggested that initial audit standards for multi-imaging should be 75% for minimum agreement, a 10% maximum for an equivocal rate, a 5% maximum for false negative and an unchanged false positive rate of 7.5% maximum. These standards will be refined with experience. Due to the nature of the database, complex queries can be made including those about histopathological data. If widely used, the database will be a useful tool to audit the accuracy of symptomatic breast imaging services and types and frequencies of symptomatic breast disease, as seen in routine settings.

Methodological and analytical aspects of simple methods for measuring iodine in urine. Comparison with HPLC and Technicon Autoanalyzer II

This work describes an optimization of a simple photometric determination of iodine concentrations in urine using a modified ceric arsenite method with ammonium persulfate as oxidant. By means of this sensitive method iodine concentrations can be determined in very small specimens (50 microL). Urine samples (105) collected from a mixed population, were analyzed for urine iodine content by the optimized ammonium persulfate method, a Technicon Autoanalyzer II and a paired-ion-RP HPLC. We found that the precision of this optimized ammonium persulfate method yields inter assay CVs of <10% for urinary iodine concentrations >10 microg/dL. Recovery of [123I]iodide added to urine in vitro was 100.9 +/- 2.4%. The detection limit was 0.0029 microg iodine. There was a high correlation between all three methods (r > 0.94 in any case) and the interpretation of the results was consistent. We conclude that this simple, manual ammonium persulfate method is suitable for urinary iodine analysis and can be performed in any routine clinical laboratory.